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WebSphere Application Server Enterprise Edition 4.0

1. Message Bean JNDIName onMessage QueueConnectionFactoryBean JNDI Entry correlation correlation JMS Listener correlation uses configuration file lt JMSConnectionFactory gt lt JMSDestination gt lt homeJNDIName gt XML Configuration File Figure 4 10 WebSphere Application Server and its relationships in the JMS architecture WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide JMS Provider We configure the JMS Provider within WebSphere Application Server by using these steps ANOoOaRWOND Expand Resources gt JMS Providers gt IBM MQSeries Select IBM MQSeries Click the Nodes tab Click Install New Select the local node Click Specify Driver Click Add Driver Select lt MQSeries install home gt java lib fscontext jar Repeat this step for providerutil jar see Figure 4 11 l H H i Time Driver file extjar CAIBMIM SeriesWavallib providerutil jar Specify Driver TI P23BK66H_samplr is Resources 4 Install Driver JDBC Providers JavaMail Sessions Selecta node on which you want to install the driver URL Providers ee s a J2C Resource Adal JMS Providers Ae E JMS Conner E JMS Destine Install Cancel B i Specify the
2. C a e aa e e Primary Key STWID and STIID Chapter 2 Overview of the OrderEntry application 13 2 3 Development environment The OrderEntry application has been developed using the new tool called WebSphere Studio Application Developer This tool integrates most of the capabilities available from other IBM tools such as WebSphere Studio and VisualAge for Java In addition WebSphere Studio Application Developer provides the GUI editors to specify the deployment descriptors according to the J2EE specification We recommend that you use WebSphere Studio Application Developer as the IDE for the examples provided in this book For more information about WebSphere Studio Application Developer refer to the Web page at http www ibm com software ad studioappdev 14 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The Business Rule Beans service This chapter explains how to use the Business Rule Beans service in building enterprise applications It includes the following topics gt Overview of the Business Rules Beans service gt Implementation of different business rules gt Performance considerations gt Deployment Note To understand the structure of the OrderEntry application and to run it read the instructions in Appendix A Downloading and installing the OrderEntry application on page 221 Copyright IBM Corp 2002 15 3 1 Overview The Business Rules Beans BRBeans
3. gt a gt r JMS destination J Output queue Entity Bean Figure 4 1 The JMS point to point model 52 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Note For completeness of the picture we added an output queue although it s not required by the JMS specification JMS Listener provides support only for an input queue In the chapter we use term JMS destination for an input queue gt JMS publish subscribe Messages are published to a JMS destination called a topic They are then distributed to all message beans that subscribed to that topic via the MQSeries message broker and JMS Listener Further processing of a message is similar to the point to point model see Figure 4 2 WebSphere Application Server topic of JMS Message Business Logic MQ Client gt gt Broker icati Listener gt Bean Bean gt Application Q interest Q defaul queue V topic Entity Bean A Figure 4 2 The JMS publish subscribe model Note Walk through point to point and publish subscribe samples are also installed with WebSphere Application Server 4 0 You can find instructions in the WAS_HOME Enterprise samples messaging doc PtoP and the WAS_HOME Enterprise samples messaging doc PubSub directories 4 2 Configuring JMS point to point for the OrderEntry application A new function in the OrderEntry application offers you the ability to receive an
4. Find Browse ea cant eo Figure 3 18 Specifying dependent rules in the Rule Management Application Note The BRBeans framework does not ensure that all dependent rules are fired Rule client implementation In WebSphere Studio Application Developer navigate to the getOrderTotal method in the ApplicationMgr class the OrderEntryWeb source application folder In getOrderTotal see Example 3 14 we populate the required parameters for both the top level rule and dependent rules fire the rule and process rule results Example 3 14 Implementation of the getOrderTotal method public void getOrderTotal Float purchaseTotal Integer amountYTD String shippingType throws Exception Float orderTotal null Create new trigger point TriggerPoint tp new TriggerPoint 44 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Disable caching for demonstration purpose tp disableCaching This array contains parameters for the main rule and dependent rules Object firingParams new Object 3 Order amount and customer YTD purchases Object discountRuleParams new Integer purchaseTotal intValue amountYTD Order amount firingParams 0 purchaseTotal Parameters for the discount rules firingParams 1 discountRuleParams Shipping type firingParams 2 shippingType Fire the rule Object result tp trigger tp firingParams OrderRules Calculat
5. gt Concurrent process This process type supports execution of the multiple tasks in parallel gt Instance cluster process This type of process provides a way to create a separate instance of a task for each value of the input parameter For example you can create an e mail managing process where all messages for a particular user are managed by a separate instance of an e mail task In other words an instance cluster process checks the value of a user ID parameter in all messages When it receives a message it tries to find a task that is responsible for managing the e mail messages for a given user If sucha task exists the process routes an e mail message to this task If a task doesn t exist the instance cluster process creates a new task gt Keep alive process This process performs two steps whenever a new message arrives on its input port Check if a running task exists It it does the process routes the incoming message to this task If there is no running task the process creates a new task and routes the incoming message to this task gt Message cluster process This process creates a new task for each incoming message gt Repeat process This process runs contained tasks a specified number of times or until some condition is satisfied gt Retry process This process runs the contained tasks repeatedly either until it succeeds or it reaches the predefined threshold limit for the number of attempts
6. gt Sequential process This process runs the contained tasks sequentially The order of the execution is specified during modeling of the application in the ABC tool gt Source cluster process This process creates a separate task for sending each outgoing message gt Swap process This process represents a finite state machine the process executes a specific task for each state This process also contains a default task that is executed when the state is undefined gt Time limit process This process stops a contained instance of a task if it runs longer than the predefined time limit This is achieved through a configurable property 9 2 2 Resource A Resource component represents a source of data database legacy application and so on In order for a JavaBeans class to be treated as a Resource component it has to implement the com ibm bpbeans Resource interface 214 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The BPBeans framework provides the com ibm bpb base ResourceBase class that implements the com ibm bpbeans Resource interface In most cases you just need to extend this class to implement your Resource The com ibm bpb base ResourceBase class implements the required methods for a Resource component plus it provides several utility methods 9 2 3 Context Context acts like a mediator between a BPBeans components and the runtime environment similar to a security context
7. End This is a Session Bean Class con con con con con con con ibn ibn ibn ibn ibn ibn ibn bpb client local LocalClientContext bpbeans ResponseListener bpbeans ResponseToken bpbeans IncompatibleMessageException bpbeans OutInPort itso roch bpb message PlaceOrderMessage itso roch bpb message NoRep yMessage Business Process Beans public class OrderEntryClerkBean implements SessionBean ResponseListener 1 Begin Business Process Beans private Object lock new Object 2 private PlaceOrderMessage _answer null End Business Process Beans Chapter 9 The Business Process Beans service 217 Following is the state in this stateful session bean public String custID public Vector items public Vector myCart public DataSource ds boolean isDirty Begin Business Process Beans method support public String bpbPlaceOrder throws IncompatibleMessageException String applicationLocation C OrderEntry BusinessProcessBeans deployed OrderEntry 3 String application OrderEntryApp 4 String clientType PlaceOrderClient 5 LocalClientContext bpbClientCtx new LocalClientContext app icationLocation application clientType 6 OutInPort oip bpbClientCtx getOutInPort PlaceOrderMessage 7 PlaceOrderMessage oMsg new PlaceOrderMessage Integer parseInt custID Integer parseInt whid
8. Cancel Finish Figure 7 8 Adding the DummyClient class as the Main class 9 Click Select when the directory is highlighted 10 In the Add Files window highlight the DummyClient class and click Add 11 Click OK 12 Select or enter DummyClient as the Main Class in the next window 13 Complete the rest of the wizard leaving the EJB References blank for the moment 7 8 3 Adding the EJB references It is easier to add the EJB references after the client Module has been completed because the tool now dynamically picks up the EJBs in the appropriate EJB module 1 Right click EJB References under the newly created Dummy Client 2 Select New 3 To add a reference use the Link drop down box to select the appropriate EJB The AAT now dynamically updates the Home Remote and Type fields as shown in Figure 7 9 150 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide SE x i Bindings An EJB reference is a logical name used to locate the home interface of an enterprise bean used by an application Name ejb CustomerBean Description Link Customer x Home jcorn ibmn itso roch wasaejb CustomerHome Browse Remote tom ibm itso roch wasaejb Customer Browse Type Entity Apply Cancel Help Figure 7 9 Adding EJB references to the client 4 Enter the name of the reference The EJB is found from the ActiveX process using the reference Name preceded b
9. File Edit View Help All Folders Rule Namespace H 6 CustomerRules H 6 DiscountRules H E OrderRules H E ShippingRules H E com Figure 3 3 Importing rule configurations in the Rule Management Application 3 2 2 General approach for implementing business rules 22 The process of implementing a business rule classifier or base in the BRBeans framework consists of three steps 1 Creating a rule implementor class This step is optional developers can use rule implementors provided with the BRBeans framework 2 Configuring a BRBeans rule in the Rule Management Application 3 Placing a call to the BRBeans rule in the rule client trigger point WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide These activities can be carried out by different individuals at different times Developers are responsible for creating rule implementors and placing trigger points in the rule client BRBeans rules can be configured in the Rule Management Application by either a domain expert or a developer Creating rule implementors Rule implementors are Java classes that encapsulate business logic These classes must implement the Rulelmplementor interface The interface has three methods gt init This method provides the initial state to the rule implementor The method is called by the framework when a BRBeans rule is first fired Rule implementor initialization parameters are configured in th
10. Then Set Application oCC XJBGetJ2EEClientContainer Application oXJB strEar strBootstrapHost strBootstrapPort strEarTempDir 7 7 3 Client container guidelines Follow these guidelines to optimize the usage of the J2EE client container Storing the client container as a global variable As for the JVM there can only be one client container per JVM Best practice is to hold the client container as a global variable Re initializing the client container By default when the client container is first initialized by calling the containers aunch method it extracts the EAR file into a random directory name in the system temporary directory In a standard J2EE Java client these files are then cleaned up when the container shuts down When the ActiveX client is restarted and the client container is re initialized another random directory name is used to extract the EAR contents The way to get around this problem is to specify the com ibm websphere client applicationclient archivedir system property in the JVM before the client container is initialized Now if the EAR file is already extracted to that location the container will re use those files Chapter 7 The ActiveX bridge service 147 Important If the client side EAR is changed this directory must be deleted and the application restarted prior to the call to the containers launch method Otherwise the container will re use the contents of the old EAR file As a
11. 3 The build process for the IBM client expects the OrderEntry ear in the directory OE_HOME 4 Microsoft Visual C must be installed in the default directory C Program Files Microsoft Visual Studio VC98 If it is not you have to edit the environment file OE_HOME corba set_common_env bat Configuring VisiBroker For this example we used an 30 day evaluation version of VisiBroker V4 5 The following setup is described based on this experience The details may slightly differ if you use a full version of the product The VisiBroker 4 5 online documentation packaged together as HTML books for C and Java is available from the following Web page http www borland com techpubs books vbcpp vbcpp45 framesetindex html Chapter 8 The CORBA services 163 To install VisiBroker 4 5 you must complete these steps 1 Install JDK 1 3 from the Web at http java sun com j2se 1 3 download windows html 2 Download the software and register by following the steps at http www borland com visibroker download vbcpp4x_steps html 3 Install the product as described in the installation guide 4 Add the environment variable VBROKERDIR which should point to the directory where VisiBroker is installed 5 Add VBROKERDIR bin to the PATH environment variable For administration purposes a GUI is shipped with VisiBroker You start it from the Windows menu bar by selecting Programs gt VisiBroker gt VisiBroker Console Figure 8 6 sh
12. 8 A customer is searched by the customer ID number If the customer is not found the error message is displayed OrderEntry application doesn t have a Web interface to create a customer If the customer is found a new Orderltems page is displayed This is the page where a customer service representative can add any number of items to the shopping cart The process of adding the order items to the shopping cart is shown in Figure 2 3 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide ltem OrderEntryServet ni com ibm itso roch wasaejb OrderEntryClerk com ibm itso roch wasaejb ltem ltemsViewBean Orderltems jsp Customer has been recognized and addSelecteditem create getSelecteditems selected an item I getitem i i i lookup EJB i i i i a H H i look p EJB i i i getltem q i i get temPrice i display JSP Figure 2 3 Adding items to the shopping cart The application offers two ways to add items gt By specifying an item ID and quantity gt By opening an item s catalog view and selecting items from the catalog Only the first method is shown in the diagram When all items are selected a customer service representative can check them out This process is shown in Figure 2 4 Chapter 2 Overview of the OrderEntry application 9 Or
13. The publishMessage method private void publishMessage String TargetTopicJNDIName String msgID String text TopicConnectionFactory oTopicConnectionFactory null TopicConnection oTopicConnection null TopicSession oTopicSession null TopicPublisher oTopicPublisher null Topic oTopic null try Context oInitialContext getInitialContext Attempt to retrieve a TopicConnectionFactory from the JNDI namespace oTopicConnectionFactory TopicConnectionFactory oInitialContext lookup OrderEntry JMS TCF if oTopicConnectionFactory null System out printIn Failed to retrieve a TopicConnectionFactory from JNDI Get the Topic where to publish our message from JNDI System out printIn Retrieving Topic from JNDI Attempt to retrieve Topic from the JNDI namespace oTopic Topic oInitialContext lookup TargetTopicJNDIName Okay we have completed the resource lookup now send the message Create a TopicConnection from the TopicConnectionFactory 82 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide System out printIn Creating a Connection oTopicConnection oTopicConnectionFactory createTopicConnection System out println Created a Connection IMPORTANT Receive calls will be blocked if the connection is not explicitly started so make sure its started System out printIn Starti
14. calls the findAllCustomers method on the EJB and then the elements method is called to return an enumeration of the results A JObjectProxy object which represents enumeration is passed back to the Visual Basic client application The enumeration contains a set of String arrays We access each String array by calling the nextElement method in enumeration However the signature of the nextElement method declares that the return value is of type Object The ActiveX bridge realizes that the object returned by CustomerList nextElement is actually a String array and handles this by returning a Variant array to the application Each element of the String array can be assigned to a String in the code The error handling around the call to Clerk findAl1Customers elements caters to the session EJB timing out Example 7 13 Handling arrays associated with COM primitives Public Function GetAl lCustomers As Variant On Error Resume Next Set CustomerList Clerk findAl1 Customers elements If Err Number amp H6003 And _ InStr Err Description java rmi NoSuchObjectException gt 0 Then Dim oCHome As Object Set oCHome g_Config EJBHomeRefs OrderEntryClerkHome Set Clerk CallByName oCHome create VbMethod Set CustomerList Clerk findAl 1Customers elements Elself Err Number lt gt 0 Then GoTo ErrorHandler 140 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide iterate through recordset a
15. customerlID 0001 fixed read only Figure 5 1 Original WorkArea A remote method receiving this WorkArea can create a nested WorkArea that inherits all the properties of the original WorkArea received from the client The remote method can then add remove and override properties in the nested WorkArea The properties in the original WorkArea are not changed but changes in the new WorkArea can override the properties in the original WorkArea Property modes discussed in the next section control what properties can be overridden by the new WorkArea Figure 5 2 shows the original WorkArea 0 with nested WorkArea 1 created by a remote method All of the properties in WorkArea 0 that are not overridden are visible in the remote method as are all the properties in WorkArea 1 Once the quantity property is set with the new value 2 in WorkArea 1 the value in WorkArea 0 is no longer visible The new value firstName is visible in WorkArea 1 but when the remote method returns WorkArea 1 is terminated it will not be accessible in WorkArea 0 Work Area 0 Work Area 1 name quantity itemID 000003 fixed normal last Name Smith read only customerlID 0001 fixed read only first Name read only itemPrice read only Figure 5 2 Nested WorkArea 98 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide If the remote method in turn calls another remote method WorkArea 1 is passed to the next method along
16. forename lt fname gt lastname lt name gt phone lt phone gt Note The vb2ejb client should be able to support the same functionality as the IBM client But we have only implemented the create method To create a customer with default values you call vb2ejb method create id 1234 forename joe lastname miller phone 01234 56789 182 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The output of the executable would be like TRACE Entering main TRACE Reading program arguments TRACE Program values TRACE forename joe id 1234 lastname miller method create phone 01234 56789 TRACE Initializing the ORB TRACE Reading the Root Naming ContextIOR from nameservice ior TRACE Getting name server TRACE By resolving the stringified IOR TRACE Constructing name entry TRACE Resolving name entry domain legacyRoot CustomerGlobal TRACE Narrowing CustomerHome TRACE Creating a CustomerBean with the following parameters TRACE CustomerID 1234 TRACE ForeName joe TRACE LastName miller TRACE Phone 01234 56789 TRACE Customer created TRACE 1234 joe miller 01234 56789 The following subsections discuss in detail what happens when the vb2ejb exe is executed Class overview Initializing the VisiBroker ORB Getting the root context by resolving the stringified IOR Binding the CustomerHome Creating a customer YYYY Y Class overview The i
17. if initialized One parameter is expected the shipping type ImplementorHelper assertParamLength parms 1 CalculateShippingCharge fire shippingType String parms 0 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide if shippingType equals EXPRESS shippingCharge expressCharge else if shippingType equals PRIORITY shippingCharge priorityCharge else if shippingType equals GROUND shippingCharge groundCharge return new Float shippingCharge The fire method see Example 3 13 invokes the dependent rules performs the calculation and returns the total order amount The names of the dependent rules called by the fire method are defined in the Rule Management Application Example 3 13 Implementation of the CalculateOrderTotal fire method public Object fire TriggerPoint tp Object target IRuleCopy rule java lang Object parms throws BusinessRuleBeansException float orderTotal 0 float orderAmount 0 int discount 0 Object resultArray null Object result null Float shippingCharge null String ruleName null if initialized Purchase amount orderAmount Float parms 0 floatValue Parameters to pass to dependent rules Object discountParams Object parms 1 Object shippingParams parms 2 The first rule is the discount rule ruleName dependentRules 0 Get discount result tp trigger nul
18. s Guide yRuleprowser ox File Edit View Help All Folders Rule Namespace H E CustomerRules DiscountRules H E OrderRules H E ShippingRules com 1 Rule Selected Rules in folder DiscountRules Status E Name a CalculateDiscount in effect me 3 CalculateDiscount wf Figure 3 12 Status of the CalculateDiscount rules after the end date change Total order discount percentage changes because only one of the BRBeans rules the rule that uses the DiscountByLevel rule implementor is found and fired see Figure 3 13 The discount percentage does not change as we add more items because the customer receives the level discount only 7 Gold discount Shopping Cart ltem ID Description ltem Price Quantity 000013 Doll_House_Furniture 24 22 1 000017 Magical_Mystery_Maze 39 83 1 000002 Radio_Controlled Plane 96 86 1 Order Total 160 91 lt Gold Discount 7 Total Order Discount 7 Figure 3 13 Total order discount after inactivating one of the discount rules 9 Change the discount value or the level required to qualify for a certain discount in one or both discount rules The discount percentages are specified as initialization parameters in the Rule Management Application They can be changed in the Implementation tab of the rule Properties window 10 Add another rule implementation such as HolidayDiscount that simply returns a discount passed in initialization parameter The fire method o
19. s call to the rules In WebSphere Studio Application Developer open the ApplicationMgr class in the OrderEntryWeb source application folder and navigate to the getOrderDiscount method The method performs the following tasks Creates an instance of the trigger point object Populates the required parameters Fires the BRBeans rule CalcuateDiscount located in the DiscountRules folder Processes results returned by the rule As you can see in Example 3 7 the rule client expects results from multiple BRBeans rules to be returned Discount percentages returned from different BRBeans rules are added together to form a cumulative percentage discount In this example multiple rules can be returned because we used the default trigger point strategies see Using strategy objects on page 24 Example 3 7 Implementation of the getOrderDiscount method public void getOrderDiscount int purchaseTotal int amountYTD throws Exception int orderDiscount 0 Create new trigger point TriggerPoint tp new TriggerPoint Disable caching for demonstration purpose tp disableCaching Pass the purchase total and amount of YTD purchases to the rule Object firingParams new Integer purchaseTotal new Integer amountYTD Object result tp trigger null firingParams DiscountRules CalculateDiscount if result null itemsViewBean setApplicationError The rule returned null else Rule successfully called Ob
20. C Specify firing parameters Add Change Delete ANE F Description OK Cancel Help Figure 3 8 Implementation properties of the CustomerClassification rule j Click OK k The CustomerClassification rule should now be in effect see Figure 3 9 _ Rule Browser eT eS File Edit View Help All Folders Rules in folder CustoamerRules Name a Status _ Start Date ee Giese CustomerRules im CustomerClassification ineffect 1 1 01 12 01 AM aj H E DiscountRules f Specials in effect 1 1 01 12 01 AM H E OrderRules Specials in effect 1 1 01 12 00 AM H E ShippingRules f Specials ineffect 1 1 01 12 00 AM Rule Namespace com v 4 La Figure 3 9 Displaying CustomerClassification status 4 Rules Implementing a trigger point 5 Implement a trigger point in the rule client a In the Navigator view of WebSphere Studio Application Developer expand the OrderEntryWeb source rules folder b Double click ApplicationMgr c Implement the getCustomerLevel method The method creates an instance of the TriggerPoint object populates the required parameters fires the rule and processes the result returned by the CustomerClassification rule Source code for the getCustomerLevel method is shown in Example 3 4 Note Caching is disabled in the rule client implementations provided in this chapter for demonstration purposes only For more informat
21. Nothing Set oProps Nothing Exit Function 7 5 Accessing Java objects methods and fields After an ActiveX client program has initialized the JVM XJB JClassFactory can be used to obtain access to Java objects and classes using JObjectProxy and JClassProxy objects When accessing a Java class or object the real Java object exists in the JVM and the automation container contains the proxy for that Java object The ActiveX program can use the proxy object to access the Java classes and objects fields and methods The XJB JClassFactory is the object from which all Java classes and objects can be accessed and instantiated 7 5 1 Primitive data type conversions The ActiveX to EJB bridge performs conversions for COM primitive data types between native Automation types and their corresponding Java primitive data types and wrapper classes as shown in Table 7 1 and Table 7 2 All other types are handled automatically by the JObjectProxy objects The client program performs primitive data type conversion through the COM IDispatch interface use of the Unknown interface is not directly supported Table 7 1 Visual Basic to Java type conversion VT_I1 byte Bye in Visual Basic is unsigned butis signed in Java See Byte Helper Function Chapter 7 The ActiveX bridge service 133 flog o vt 14 Currency poe CY pe a Currency Helper Function Strings VT_ VTBSTR char Date C DATE E is not supported as a primitive Table 7
22. Setting up the OrderEntry application database The process of creating and populating the OrderEntry database is straightforward if you use Windows 2000 or Window NT 1 2 3 Open a command prompt Change the directory to 0E_HOME DB2 Run the following command CreateDB_OrderEntry bat The CreateDB_OrderEntry bat file logs setup information to the C temp OrderEntry log file Examine this file You need to fix any problems before you attempt to install and run the OrderEntry application Setting up the BRBeans database To create a BRBeans database follow these steps 1 2 3 Open a command prompt Change the directory to 0E_HOME BRBeans Run the following command brbdb bat The script logs the setup information to the C Temp BRBeansSetup log file Examine this file You need to fix any problem before you attempt to install and run the OrderEntry application Configuring WebSphere Application Server Before you can install the OrderEntry application you have to create two datasources one to access the OrderEntry database and another the BRBeans database and create an application server To create the datasources complete the following steps If you need help refer to the WebSphere Application Server Advanced Edition documentation in the IBM WebSphere InfoCenter at http www ibm com software webservers appserv doc v40 aee index html 1 Start the WebSphere Administrative Server by clicking
23. and application_server represents the name of the application server on which the trace will be enabled 3 In the right hand pane of the WebSphere Advanced Administrative Console window select the Services tab 4 On the Services tab select Trace Service from the list of services see Figure 6 3 General Advanced File Transaction JVM Settings Services Custom Service EJB Container Service Web Container Service Session Manager Service Object Level Trace Service Performance Monitoring Settings Object Request Broker Apply Reset Help Figure 6 3 Services tab 5 Click Edit Properties The Trace Service dialog is displayed 6 In the Trace Service dialog click the button to the right of the Trace specification field to open the Trace dialog see Figure 6 4 Note In the Trace Service dialog box you may also specify an output file to log application server trace messages to including those generated by the Internationalization service E a General Node P23BK58A Application Server Default Server Trace specification d Trace output file Trace outputfile Standard error Click this butto Standard output C Specify ok canei Hen Figure 6 4 Trace Service dialog box 118 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 7 Inthe Trace dialog expand Components gt com gt ibm to see I 18nContextlmpl in the
24. but CustomerWrapper objects which do the exception handling for the Customer calls Example 8 3 shows the code fragments that create the binding to the CustomerHome The first step is to create a name structure containing the link to the entry of the CustomerHome The next step is to resolve this name by the naming service In the last step the resolved CORBA object is narrowed to an CustomerHome object Example 8 3 Binding the CustomerHome const string CustomerFactory NS_ENTRY domain legacyRoot CustomerGlobal com ibm itso roch wasaejb CustomerHome_ptr CustomerFactory _customerHome CustomerFactory CustomerFactory const CosNaming NamingContext_ptr rootContext get naming entry in Name structure format t println Constructing name entry CosNaming Name name MyOrb stringToName NS_ENTRY CORBA Object_var homeObj NULL t printIn Resolving name entry NS_ENTRY s homeObj rootContext gt resolve name if CORBA is_nil homeObj err printIn apparently resolve FAILED t println Narrowing CustomerHome _customerHome CustomerHome narrow homeObj 172 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide if CORBA is_nil _customerHome err printIn narrow returned nil on CustomerHome CosNaming Name MyOrb stringToName const string nameString Trace t char sep string token CosNaming Name nam
25. com ibm itso roch wasaejb CustomerKey virtual public OBV_com ibm itso roch wasaejb CustomerKey virtual public CORBA DefaultValueRefCountBase 4 Implement the two methods of the CustomerKey class in the CustomerKey_lI cpp file CORBA Boolean com_ibm_itso_roch_wasaejb_CustomerKey_Impl equals const java lang Object amp obj cout lt lt Entering CustomerKey_Imp l equals lt lt endl CORBA Boolean areEqual FALSE CORBA ValueBase tmp CORBA ValueBase amp obj CustomerKey_ var ckey CustomerKey _narrow tmp if ckey CORBA ValueBase NULL char keyVall VtlUtil WStringValueToString ckey gt primaryKey char keyVal2 Vt1Util WStringValueToString primaryKey areEqual strcmp keyVall keyVal2 0 return areEqual 174 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Note The getters and setters of OBV_com ibm itso roch wasaejb CustomerKey have to be used to access the member primaryKey CORBA Long com_ibm_itso_roch_wasaejb_CustomerKey_Impl hashCode CORBA Long hash 0 CORBA Long prime 31 char key Vt1lUtil WStringValueToString primaryKey try for CORBA Long i 0 i lt strlen key i hash prime hash key i catch cerr lt lt Caught an unexpected exception in CustomerKey hashCode lt lt endl return hash Note The algorithm for the
26. gt Corba support at http www ibm com software webservers appserv doc v40 aee index html 8 2 2 Interoperability with an EJB The most common way of interoperation with WebSphere Application Server involves EJBs Therefore it is worth of taking a closer look at the following two scenarios gt EJB as a CORBA client gt EJB as a CORBA server EJB as a CORBA client If the EJB is the CORBA client the binding works as described in Figure 8 2 on page 155 EJB as a CORBA server The EJB server provides the servant objects the EJBs that client applications need to access In this scenario the following sequence of events occur The client ORB has to be initialized when its process is started The client locates the home interface object of the EJB through the naming service The home interface object locates the EJB or creates it if it doesn t exist The client creates the stub The client sends its request through the stub to the EJB aPN Figure 8 5 shows the involved components Naming service xe Client y Web Sphere EJB server application A f soe EJB container f Home 4 K i yo Stub Client P Ee Server P i an Cll Emitter Client environment Server environment Figure 8 5 An EJB as CORBA server Currently the access of a C client to an EJB is slightly restricted in WebSphere Application Server 4 0 Session beans are fully supported For entity beans only a subset of
27. gt platinumLevel classification PLATINUM LEVEL else if amount gt goldLevel classification GOLD LEVEL else if amount gt preferredLevel classification PREFERRED_LEVEL return classification public String getDescription 48 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide return Returns customer classification public void init Object parms String dependentRules String userDefinedData IRuleCopy rule throws BusinessRuleBeansException Three parameters are expected ImplementorHelper assertParamLength parms 3 CustomerClassification init Store the initialization parameters preferredLevel Integer parms 0 intValue goldLevel Integer parms 1 intValue platinumLevel Integer parms 2 intValue initialized true Chapter 3 The Business Rule Beans service 49 50 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Extended Messaging Service This chapter discusses the Extended Messaging Service JMS Listener and the main components of the JMS messaging implementation within WebSphere Application Server Enterprise Edition It introduces and discusses the point to point messaging model This model is applied to the OrderEntry application to illustrate real world use This chapter also includes sample code and a configuration using WebSphere Application Developer the JMSAdmin tool MQSeries Exp
28. locale or time zone to the server Although the technique is simple it has serious limitations gt Parameter lists become longer gt Extra parameters may need to be added to methods that do not use the information just to pass the information through the call chain gt Adding extra parameters to a deployed application is inherently error prone gt It may be impossible to add parameters to applications that are not easily modified such as legacy applications 6 1 1 Computers located in different locales Client and server processes can run on computers that have a different locale setting For example a Spanish client may invoke a business method on an object that resides on an American server Some business methods can be locale sensitive For example a business method might return a sorted list of strings the Spanish client will expect that list to be sorted according to the Spanish collating sequence not in the server s English collating sequence Since data retrieval and sorting procedures run on the server the locale of the client must be available in order to perform a legitimate sort A server may also have to return strings containing date time currency or exception messages formatted according to the client s locale 6 1 2 Computers located in different time zones Client and server processes can execute in geographical locations having different time zones For example suppose a vendor makes the claim that orde
29. lt JMSConnectionFactory gt OrderEntry JMS TCFBean lt JMSConnectionFactory gt lt JMSDestination gt OrderEntry JMS listen lt JMSDestination gt lt JMSDestinationType gt javax jms Topic lt JMSDestinationType gt lt JMSSubscriptionDurability gt durable lt JMSSubscriptionDurabil ity gt lt JMSSubscriptionName gt Listener lt JMSSubscriptionName gt lt MaxRetries gt 6 lt MaxRetries gt lt MaxSessions gt 1 lt MaxSessions gt lt Listener gt lt Config gt Chapter 4 Extended Messaging Service 81 4 3 6 The message bean for the publish subscribe model The same rules for the message bean in the point to point model apply to the publish subscribe model Refer to 4 2 6 The message bean on page 67 Placing a message at a topic JMS destination Example 4 9 shows a publishMessage method This method can be used for publishing messages to a JMS destination topic The objects for publishing to a topic differ from those used to send messages to a queue in these key areas A topic connection factory is used to create a TopicConnection object The topic connection object is used to connect to a JMS destination topic The session is maintained through a TopicSession A topic publisher is used to publish to the Topic topic YYY Yy The difference in the variable types used to publish rather than send a message can be seen Compare it to Example 4 6 on page 72 Example 4 9 Placing a message at a JMS destination topic
30. strAppClientJar As String strEARTempDir As String Dim oProps As Object Dim oCC As Object Dim astrAppParams 0 As String Initialize the J2EE Client Container Before initializing the Client Container set the System Property that tells it what directory to extract the EAR file to If we don t do this then a new directory will be created each time we launch the Client Container and will not get cleaned up If Trim strEARTempDir lt gt Then XJBPutProperty oXJB oXJB FindClass java lang System getProperties _ com ibm websphere client applicationclient archivedir _ strEARTempDir 1 1 End If Here we are creating a launchClient object which is supplied in appclient jar supplied with WebSphere Client or Server install Notice that we are eliminating the need to store the Class Proxy object returned by FindClass We are using as a temporary variable and immediately creating a new instance Object Proxy and throwing the Class Proxy away Set oCC oXJB NewInstance oXJB FindClass com ibm websphere client applicationclient 1launchClient Create a java util Properties object to use in our launchClient J2EE API Set oProps oXJB NewInstance oXJB FindClass java util Properties Add properties to the Properties object jnitonly true is required to avoid running the Java Client that s stored in the EAR file BootstrapHost xxxx The name of the WebSphere server where your EJB s are
31. 100 iorfile sizeof iorfile 1 0 strncpy iorfile fileName sizeof iorfile 1 std ofstream outFile outFile open iorfile if outFile fail std cerr lt lt Cannot open file lt lt iorfile lt lt std endl else CORBA String_var string_ref global_orb gt object_to_string obj outFile lt lt char string_ref lt lt std endl outFile close std cout lt lt Writing IOR of root naming context to file lt lt fileName lt lt lt lt std endl tmp_ref global_orb gt resolve_initial_references NameService CosNaming NamingContextExt_var default_context CosNaming NamingContextExt _narrow tmp_ref assert CORBA is_nil default_context writelOR default_context com ibm itso roch credit ROOT_IOR_FILENAME Exporting object reference The next step is to export the object reference to the namespace Since we don t want to export our reference directly under the naming root we first have to create a naming context Underneath that we put the CreditInstitute reference The code fragments are shown in Example 8 14 Chapter 8 The CORBA services 197 Example 8 14 Exporting object reference CosNaming NamingContext_ptr create_demo_context CosNaming NamingContextExt_ptr default_context const char demo_name_string IT_THROW_DECL CORBA Exception CORBA Object_var context_as_obj First see if the name is already bound try catc
32. 2 Java to Visual Basic type conversion Java type Visual Basic type byte VT_I1 Byte Byte in Visual Basic is java lang Byte unsigned butis signed in Java See Byte Helper Function boolean VT_BOOL Boolean java lang Boolean short VT_l2 Integer java lang Short int VT_l4 Long java lang Integer long VT_CY Currency java lang Long float VT_R4 Single java lang Float double VT_R8 Double o lang Double java java lang String String VT_ VT_BSTR o I VTBSTR Sra o char VT_BSTR String java lang Character VT_DATE Date Not available java util Date objects are represented as normal Object Proxy objects For example to correctly invoke a Java setNumberOfLegs method which takes a Java int as a parameter the Visual Basic code would have to pass a COM Long primitive as the argument anAnimal setNumberOfLegs CLng 4 Conversion helper functions are needed where automatic conversions are not possible 134 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Byte helper function Because the Java Byte data type is signed 127 through 128 and the Visual Basic Byte data type is unsigned 0 through 255 you need to convert unsigned Bytes to a Visual Basic Integers which look like the Java signed byte See Example 7 5 Example 7 5 The Byte helper function Private Function GetIntFromJavaByte Byte jByte as Integer GetIntFromJavaByte CInt jByte 128 Mod 256 128 End Function Curr
33. 4 0 A Programmer s Guide 7 Close the rule management application Running the OrderEntry application Now you re ready to test the application To do that perform the following steps 1 Make sure the DB2 services are started 2 Start the OrderEntry Server application server 3 4 Point your browser to Start Internet Explorer Netscape doesn t show pages correctly http localhost lt port_for_OrderEntryServer gt OrderEntry index htm Here lt port_for_OrderEntryServer gt is the port number that you used in step 6 on page 226 In the browser window click Start the OrderEntry application 6 The application represents the online ordering system a Specify a customer ID in the range between 0001 and 0015 b On the Select the Items Web page specify an item number in the range 000001 to 000100 and the quantity c The alternative method is to click Search Catalog link and select the items from the catalog When you are done click Check Out to record you order ActiveX application client specific instructions If you plan to run the ActiveX application client on your workstation you need to perform the following configuration steps 1 Install WebSphere Application Server Client on your client system see Installing the Advanced Edition client base in IBM WebSphere InfoCenter Install the ActiveX Client support see Installing ActiveX client support Windows only in the IB
34. 6 e Proceed through the wizard and click Finish f Select No in the Regenerate Code dialog box Import the BRBeans rule configurations file The file contains the configuration for the BRBeans rules provided with the OrderEntry sample application a In the WebSphere Administrative Console start OrderEntryServer Important The Rule Management Application needs to access the Naming service As a result you have to start an application server prior to starting the Rule Management Application b Start the Rule Management Application i Open a command prompt and change the current directory to WAS_HOME Enterprise bin ii Issue the following command rulemgmt 0E_HOME BRBeans brbeansOrderEntryProperties Important The brbeansOrderEntryProperties file contains WebSphere server host and port information as well as the JNDI names of BRBeans EUBs If you are accessing the WebSphere server remotely modify the host and port information before using the Rule Management Application BRBeans EJBs JNDI names specified in the properties file must match the JNDI names used in the BRBeans configuration in step vii on page 20 c In the Rule Management Application select File gt Import d Select the rule configuration file browse to OE_HOME BRBeans and select OrderEntryBRBeansRules xnml e Click OK After you import the XML file the Rule Management Application should look like the example shown in Figure 3 3 15 x
35. 900 schemaName A_USER nameservice ior directory lt your ior directory path gt You have to change gt system if you use a remote host gt nameservice ior directory if you plan to run the test using Orbix2000 The second file is almost identical it just doesn t have the last line 226 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide You can modify these files after you install the OrderEntry application and before you run it One file is located in the WAS_HOME installedApps Order_Entry_Application ear OrderEntryWeb war directory see Figure A 3 Another file is located within Deployed_OrderEntryEJB jar which you can find in the WAS_HOME l installedApps Order_Entry_Application ear directory Important If you plan to run the application on the local machine and don t want to install Orbix2000 you don t have to modify these files EN OrderEntryWeb war lol x File Edit View Favorites Tools Help lt Back v fy A Search G Folders CAHistory as Os xX A Ev c Ee Folders x C etc aji installableApps sl installed pps CI WEB INF H Order_Entry_Application ear ma META INF 8 ApplicationError jsp Qe Sy Rens DisplayCustomer jsp El images N GetCustomer jsp H E META INF index html El theme OrderConfirmation jsp E WEB INF OrderItems jsp sampleApp ear
36. ActiveX bridge Configuring the client container and client side EAR file Initializing the JVM Launching the client container Developing and Debugging Using the bridge from a development environment Instantiating and Invoking Java objects through the bridge Best practice programming guidelines Error handling Class reference Note To understand the structure of the OrderEntry application and to run it read the instructions in Appendix A Downloading and installing the OrderEntry application on page 221 Copyright IBM Corp 2002 121 7 1 Introduction Many organizations have made considerable investments in COM based technologies such as Visual Basic Visual C and Active Server Pages ASP To save re developing these services as J2EE components the ActiveX bridge offers the ability to attach both Activex clients and ActiveX servers to EJBs by initializing a JVM within the ActiveX process The bridge enables access to all Java classes and objects within the JVM and remains attached to the process until that process terminates The suggested approach is to take advantage of the WebSphere Application Client architecture by launching a J2EE client container CC in the attached JVM This provides the COM process with simple access to J2EE services and requires minimal configuration since the EJB stubs are already contained in the Enterprise Archive file EAR file Figure 7 1 shows the position of
37. BRBeans strategies combining strategy 25 filtering strategy 25 finding strategy 24 firing strategy 25 BRBeans Trigger Point 16 business logic 16 Business Process Beans BPBeans 3 Business Process Beans service 209 business process management 4 business rule 16 18 23 39 dependent rule 41 Business Rules Beans BRBeans 3 Byte helper function 135 C C CORBA client configuring the environment 163 problem determination 185 VisiBroker client 177 C CORBA SDK 162 C CORBA server 187 configuring Orbix 188 configuring the environment 188 connecting to an Orbix server 190 problem determination 206 C CORBA software development kit SDK 162 caching 46 caller context 108 caller internationalization 109 accessing 113 case sensitivity 137 chg command 58 class module 127 classification rule 18 classified rule 38 classifier rule 26 38 client 107 client application components 127 client container 122 147 148 client container approach 129 client interface 126 Client side Internationalization CSI policy 108 111 CMT container managed transaction 85 coexistence 160 COM Component Object Model 121 combining strategy 25 35 37 Common Object Request Broker Architecture CORBA 154 compensation pair process 214 Component Object Model COM 121 concurrent process 214 container managed transaction CMT 85 Controller 124 CORBA 102 building the test client 200 C CORBA clients for the OrderEntry application 163 connec
38. Context ctx getInitialContext UserWorkArea workArea getWorkArea ctx String id String workArea get customerID String lastName String workArea get lastName String firstName String workArea get firstName Notice that the get method does not throw any exceptions If no WorkArea was associated with the current thread or it did not contain a property with the name specified the get method returns null 5 2 5 Terminating WorkArea Always terminate WorkArea when finished using it This must be done by the same process that created WorkArea Attempting to call the complete method outside the bean or servlet that called the begin method will result in a NotOriginator exception Since this exception indicates an application coding error we include the WorkArea name in the information written to the log We get the name by calling the getName method If we always use the name of the servlet or bean that created WorkArea as its name this error will be easier to debug Example 5 5 shows a method to terminate WorkArea Example 5 5 Terminating WorkArea import com ibm websphere workarea private void terminateWorkArea Complete WorkArea associated with this thread try workArea complete Ignore this exception since we were trying to terminate anyway catch NoWorkArea e This exception indicates that this WorkArea was created by some other servlet catch NotOriginator e flexLog WorkA
39. Edition side WebSphere Application Server as the JNDI directory server contains the JMS Listener service and the message bean enabled OrderEntry application To enable JMS Listener on the WebSphere Application Server side perform these steps a Configure base JMS support b Configure the JMS Listener support by modifying the XML configuration file It contains the listener stanza which links JMS destinations to listeners and listeners to message beans 4 2 2 Defining physical queues The JMS Provider in our case IBM MQSeries provides the physical queues used in the point to point model MQSeries Explorer is used for creating queues Two queues are created within the MQSeries Explorer by right clicking the local machine node and then choosing New gt Local Queue see Figure 4 5 We name them gt Qin This is the JMS destination for incoming messages see Figure 4 3 on page 54 gt Qout This queue is used to send a confirmation message back ie Console Window Help O la x Action wiew Favorites I e mlm e 2 S re A ia Set Tree Favorites Name Queue Type Current Depth _ Cluste E DEFAULT Local 0 C Console Root E IBM MQSeries C Queue Managers E i p23bk66h i Queues a H Advanced lias Queue C Clusters Hated Model Queue ZPO eit Remote Queue Definition View gt Arrange Icons gt Line up Icons Help Creates a new local queue Fig
40. Integer parseInt did items 8 ResponseToken token oip sendRequest oMsg 9 token addResponseListener this 10 synchronized _lock while _answer null System out printIln OrderEntryClerkBean pbpPlaceOrder before locking until answer arrives from BPBean Application try _lock wait Block the current thread catch InterruptedException e End while System out print n OrderEntryClerkBean pbpPlaceOrder awoke because answer arrived from BPBean Application _answer set by call to responseArrived before unlocking this thread return Integer toString _answer getOrderlId Called by BPBeans from a BPBeans thread public void allRespondersClosed ResponseToken rt 11 synchronized _lock if _answer null _answer new NoReplyMessage _lock notify Called by BPBeans from a BPBeans thread 218 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide public void responseArrived ResponseToken rt java io Serializable orderId 12 synchronized _lock if _answer null if orderId instanceof PlaceOrderMessage _answer PlaceOrderMessage orderId _lock notify End Business Process Beans method support The most interesting lines are highlighted The following list explains each line using corresponding numbers in superscript 1 This class implements the ResponseListener interface It means that this class
41. JMS JNDI Entry correlation Send JMS definition q Send JMS JNDI Entry binding binding w f W Default queue QOut MQSeries MQSeries message broker Queues Figure 4 25 The JMSAdmin tool in the publish subscribe architecture 78 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide An input file such as the one shown in Example 4 7 can be used to specify all JMS resources in the JMSAdmin tool This configuration defines three topics news sport and weather A listener topic listen is defined All messages arriving for any topic in the OrderEntry JNDI path OrderEntry are routed to this JMS Listener Example 4 7 JMS resources defined using a JMSAdmin script JMSpsSetup scp Example script to add administered objects for the JMS pub sub into a JNDI namespace Apply this script using the command JMSAdmin lt JMSpsSetup scp Create the jms subcontext OrderEntry JMS If the subcontext already exists the def command will generate an unable to create context error which may be ignored Def ctx OrderEntry chg ctx OrderEntry Def ctx JMS chg ctx JMS Define the TopicConnectionFactory for the client This uses all the default settings which map to the default queue manager A non default queue manager can be specified using the qmgr name property Def
42. Java and the application interface is limited to the fundamental methods see the discussion in 7 2 1 Designing an ActiveX client program on page 124 7 7 1 Visual Basic guidelines There are several generic guidelines for writing and deploying an ActiveX client program Launching the application or IDE In order to give your IDE access to the ActiveX bridge you must launch the IDE after setting the environment variables set by running the setupCmdLineXJB batch file Failure to do this prevents the ActiveX process from being able to initialize a JVM The easiest way to do this is to precede the IDE executable or the name of the ActiveX application with the launchClientXJB batch file which calls setupCmdLineXJB before launching the IDE The batch files are in the WebSphere install directory lt WebSphere_install_directory gt WebSphere AppClient Enterprise bin For example if the IDE is Visual Basic Version 6 use a DOS prompt to navigate to the location of the batch files Then enter either of the following commands launchClientXJB VB6 EXE launchClientXJB MyApplication vbp It is very similar for VBScript files You can enter either of the following lines JaunchClientXJB MyScript vbs JaunchClientXJB script Mysrcipt vbs Storing the XJB ClassFactory globally Once a JVM is loaded into an ActiveX process it can t be unloaded and re initialized Therefore it makes sense to keep the reference to the XJB ClassFactory throughou
43. Java bin jmsadmin InitCtx OrderEntry JMS gt dis ctx Contents of InitCtx OrderEntry JMS com ibm mq jms MQQueue com ibm ejs jms mq JMSWrapkAQueueConnect ionFactory com ibm mq jms MQQueue 3 Object lt s gt Context lt s gt 3 Binding lt s gt 3 Administered InitCtx OrderEntry JMS gt Figure 4 9 The output from the dis ctx command in the JMSAdmin tool You can delete queue definitions by entering the following command and passing the name of the queue to be deleted as a parameter Del q Qin The queue connection factory The queue connection factory is an interface used to create queue objects for use within Java applications A JMS connection is a client s active connection to its JMS Provider queue We have to define the queue connection factory too While within the OrderEntry JMS JNDI context we create the queue connection factory by entering the following command Def WSQCF QCF This creates the WebSphere connection factory including default parameters as seen in Figure 4 9 WebSphere queue connection factories support transactions in JMS message beans You can find further information about this in 4 4 1 Transaction support on page 84 The JMSAdmin tool supports a number of different queue connection factories two of which are relevant to WebSphere Application Server gt Standard non transactional connection factory Defined in the JMSAdmin tool as QCF gt Transactional co
44. Listen JMS JNDI Entry Message Bean JNDIName onMessage QueueConnectionFactoryBean JNDI Entry JMS Listener correlation correlation correlation uses configuration file lt JMSConnectionFactory gt lt JMSDestination gt lt homeJNDIName gt listener stanza of the JMS XML Configuration File Figure 4 17 The XML configuration file and its relationship to other components The XML configuration file we used for our example is shown in Example 4 2 The name of the message bean is StockDeliveryUpdate Example 4 2 XML configuration file used in our OrderEntry application lt Config gt lt Pooling gt lt Timeout gt 100636 lt Timeout gt lt Threshold gt 36 lt Threshold gt lt Pool ing gt 66 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide lt Listener gt lt HomeJNDIName gt OrderEntry JMS StockDel i veryUpdat e lt HomeJNDIName gt lt JMSConnectionFactory gt OrderEntry JMS QCF lt JMSConnectionFactory gt lt JMSDestination gt OrderEntry JMS Qin lt JMSDestination gt lt MaxRetries gt 6 lt MaxRetries gt lt MaxSessions gt 1 lt MaxSessions gt lt Listener gt lt Config gt 4 2 6 The message bean When a message arrives at the JMS destination JMS Listener gets this message and passes it to the message bean that has bee
45. Naming Service allows you to bind one or more logical names to an object reference ina naming space It also allows your client applications to use the Naming Service to obtain an object reference by using the logical name assigned to that object Figure 8 2 looks at the technical details involved in the process of binding a client to a server object called servant Client environment Naming Serer environment service Root Server Implementation process repository Domain eRe Implementation Client gt C Servant OR p lt Servant definition 24 object LA 4 Stub lt object Object reference Adapter gt Client lt _ _ Server ORB gt ORB IIOP Figure 8 2 CORBA method call in detail Chapter 8 The CORBA services 155 156 In the server environment there are basically the server process and the implementation repository which stores information about all server processes The server process itself exists of the server ORB the Object Adapter and the servant objects The Object Adapter BOA or POA dispatches the incoming requests from the ORB to the various implementation objects servants When the server process is started it has to export the references of the objects it hosts One way is to register the objects with a naming service The naming service stores an object reference in the form of an interoperable object reference IOR An IOR is a string representation of an object r
46. Platform A Figure 8 4 Position of CORBA in the J2EE architecture Chapter 8 The CORBA services 157 The J2EE specification version 1 2 defines how the Java Remote Method Invocation RMI protocol is mapped onto the IIOP wire transfer protocol referred to as RMI over IIOP RMI IIOP In this version of the specification the J2EE components don t have to support this protocol With J2EE version 1 3 clients of EJBs are required to use the RMI IIOP APIs and the EJB servers themselves have to be accessible by IIOP This allows EJBs to act as CORBA objects If a CORBA client wants to access an EJB object it is important to be aware of some restrictions The Java interface java io Serializable implemented by HashMap Date File Integer String Throwable and so on is mapped to the CORBA valuetypes The consequences are gt The client has to support the CORBA valuetypes gt Each Java serializable to be used in the interface between the client and the server for example as parameter or return value has to be re implemented in the language of the client because they are pass by value The implementation of Java serializables as value types in C or another language can require a significant development effort as you can see in Building the CustomerKey valuetype on page 174 Note Valuetypes were introduced by the CORBA 2 3 specification Many third party ORBs don t yet implement this specification or do
47. ResponseListener interface It is invoked when a response for a message comes back Note the usage of the _lock object in Example 9 1 on page 217 220 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Downloading and installing the OrderEntry application If you want to run the sample application or to browse the source code you need to download the ZIP file from the Redbooks Web page at http www redbooks ibm com This appendix explains Downloading the OrderEntry application ZIP file Unzipping the OrderEntry application ZIP file Configuring WebSphere Application Server gt gt gt gt Installing the OrderEntry application Copyright IBM Corp 2002 221 Setup instructions The following sections provide instructions for downloading and installing the OrderEntry application files The assumption are gt gt You are familiar with administrative tasks for WebSphere Application Server You have enough authority to access and manipulate DB2 and WebSphere Application Server Environment The development described in this redbook was done using the following configuration gt gt gt Operating system Windows 2000 Database IBM DB2 UDB v7 2 Application server WebSphere Application Server Enterprise Edition v4 0 Development environment WebSphere Studio Application Developer Make sure you have the WAS_HOME environment variable set it should point to the installatio
48. TCF TCF now define a TopicConnectionFactory for the Listener Note the use of a WebSphere TCF Def wstcf TCFBean Define the Topics naming the Topics to be used Def t news topic OrderEntry news Def t sport topic OrderEntry sport Def t weather topic OrderEntry weather and the general topic used by the listener Def t listen topic OrderEntry Display the current context dis ctx end Chapter 4 Extended Messaging Service 79 The JMS destinations In the publish subscribe model Java applications publish messages to topics The MQSeries message broker routes these to interested subscribers JMS Listener is a subscriber refer to Example 4 7 Three topics news sports and weather are defined The listen topic given a JNDI path of OrderEntry acts as a wild card Posting a message to news sports or weather results in the JMS Listener listen responding to that message Topic connection factory The topic connection factory is an interface used by a Java application to create topic connection objects These objects allow messages to be placed on that topic It is used by the JMS Listener to retrieve messages from the topic The messages are then passed to message beans associated with that JMS Listener Two types of topic connection factories are available gt A standard non transactional connection factory Defined in the JMSAdmin tool as TCF gt A tr
49. The Visual Basic OrderEntry client application 0 0 00 e eee eee 124 7 2 1 Designing an ActiveX client program 0 0 ee 124 7 2 2 ActiveX client interface 0 2 0 tees 126 7 2 3 Installing the client application 0 2 0 eee 126 7 2 4 The client application components 0 0000 c eee ee 127 7 3 Initializing the JVM uo cie redaden daa i tee ee 128 7 4 Using a J2EE client container 0 eee 129 7 4 1 Client container approach 0 0 0 tees 129 7 4 2 No client container approach 0 0 ee 129 7 4 3 Optimized container approach 0 et eee 131 7 4 4 Components of the client side EAR file 0 00 c eee eee 131 7 4 5 Launching a standard Java J2EE application in a client container 131 7 4 6 Launching a client container in an ActiveX process 00 e eae 131 7 5 Accessing Java objects methods and fields 0000 0 eee eeeeee 133 7 5 1 Primitive data type conversions 0 0 c eee eee 133 7 5 2 Accessing a Java claSS 1 0 eee 136 7 5 3 Accessing Java objects 0 0 0 eee 136 7 5 4 Invoking Java methodS 0 cette 137 7 5 5 Handling arrayS 0 tees 140 FeD G PRM e se ia sas cog seek tay af sgh din ues Reda nk ceases oa E NE ENDED cee ct Sa SABC ceases 141 TE Eror Nanding Aoin eee EDs Ha ML ee SAS Se has ak Bk coe aia Be le oN 142 7 7 Good programming guidelines 0 0 ccc eae 144 7 7
50. Trace dialog closes 11 Click OK in the Trace Service dialog The Trace Service dialog closes 12 Click Apply on the Services tab The changes are applied Note Clicking Apply enables the trace and makes the trace persistent across server shutdown and restart To disable the tracing function follow the above steps selecting None instead of All from the Trace window pop up menu The icons in the Trace dialog will return to gray to indicate the trace is disabled Restart the application server Messages tracing the function of the Internationalization service are output to the file specified in the Trace Service dialog 120 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The ActiveX bridge service This chapter discusses the ActiveX to EJB bridge a technology that enables Component Object Model COM applications and services to connect to EJBs in WebSphere and leverage other J2EE services It covers the components of the bridge and discusses installation and configuration issues It also uses a sample COM client that has been modified to take advantage of the bridge technology using code samples to demonstrate some p rogramming guidelines There is also a reference to the classes and methods provided by the bridge at the end of the chapter This chapter covers the following topics gt gt gt The ActiveX bridge components Supported languages and platforms Enabling COM technologies to use the
51. Type a file name and display name Click Next Figure 7 7 gi PO NS 4 Create Application Client Wizard Specifying Application Client Module Properties Enter a display name and file name for your application client module The display name is used to identify the application client module Select a parent application from the list or leave blank to create a stand alone module Fu Enter the display name and file name of your application client module Application clients have a jar extension Containing application cAOrderEntyOrderEntry ear x Browse Display name JOrderEntryClient File name fOEClientjar Description he Application Client for the Order Entry pplication Figure 7 7 Create Application Client Wizard in the Application Assembly Tool AAT 6 Add the DummyClient class see 7 8 1 Setting up the Main class on page 148 7 Click Add 8 Click Browse and navigate to the directory where the DummyClient class is located Figure 7 8 Chapter 7 The ActiveX bridge service 149 4 Create Application Client Wizard Adding Files Specify the files to be included in your application client module Click Add to import files to your application client module To remove a file select the file and click Remove k Select root directory E x Files 4 Add Files Ok File name fOrderEntry Select Files of type Root Directory war ear jar zip
52. WebSphere Application Server Advanced Edition Figure 1 1 presents this difference in a graphical manner 2 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Enterprise Edition Function and QOS Base J2EE Server and Web Services Time m Figure 1 1 The difference of Enterprise Edition and Advanced Edition in time As time goes by WebSphere Application Server Enterprise Edition will still offer the additional functions and services on top of WebSphere Application Server Advanced Edition 1 2 WebSphere Enterprise Services The newest part of the WebSphere Application Server Enterprise Edition Version 4 0 is a group of eight services called WebSphere Enterprise Services Business Rule Beans BRBeans Extended Messaging Service Java Message Service JMS Listener Shared WorkArea Internationalization ActiveX bridge CORBA C Software Development Kit SDK CORBA interoperability Business Process Beans BPBeans as the technical preview vvvvvvvy The primary goal that IBM tries to achieve with WebSphere Enterprise Services is to satisfy a growing demand from the enterprises to solve the most complex problems As you can see from the list of WebSphere Enterprise Services they include functionality that is not available in the J2EE v1 2 specification The IBM strategy is to expand WebSphere Application Server value by adding the new enterprise level services in two m
53. Zm200 MD Foit_servant_base_overrides obj it_servant_base_overrides cxx it_servant_base_ overrides cxx gt The output from linking the executable is link out server exe DEBUG NOLOGO server obj CreditInstituteC obj it_random_funcs obj it_print_funcs obj CreditInstituteS obj com_ibm_itso_roch_credit_CreditInstituteImp obj it_servant_base_overrides obj LIBPATH lt orbix_home gt orbix_art 2 0 cxx lib it_naming 1ib it_genie lib kernel32 1i1b ws2_32 1ib advapi32 lib user32 lib it_dynany lib it_poa lib it_art lib it_ifc lib cd F Henning oe corba server ejb2orbix Running the server You run the server by executing two commands cd 0E_HOME corba server ejb2orbix start_server The output of the executable is like Initializing the ORB Writing IOR of root naming context to file nameservice ior Waiting for requests Note If you get an error make sure that the Orbix services are started by executing the start_OrderEntry_services command The following subsections explain in detail what is happening when server exe is started Class overview Initializing the Orbix ORB Creating a POA Creating and activating servant objects Connecting to nameservice Exporting object reference Putting the ORB into an active state Handling requests vvvvvvvyy 194 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Class overview The main program handles basically the POA_Manager the POA and a CreditIn
54. a JMS destination queue are declared at the beginning of the method body They are QueueConnectionFactory Used to create a queue connection QueueConnection The actual connection to the queue Chapter 4 Extended Messaging Service 71 QueueSession Manages the session from the time the connection is started oQueueConnection start to the time it is closed oOueueConnection close QueueSender Used to send the JMS message Example 4 6 Placing a message at a JMS queue destination The putMessage method private void putMessage String TargetQueueJNDIName String msgID String text throws Exception QueueConnectionFactory oQueueConnectionFactory null QueueConnection oQueueConnection null QueueSession oQueueSession null QueueSender oQueueSender null System out printIn StockDeliveryUpdateBean request to put message text we casi A try InitialContext oInitialContext new InitialContext iy Obtain the queue connection factory from JNDI System out printIn StockDeliveryUpdateBean find QueueConnectionFactory oQueueConnectionFactory QueueConnectionFactory oInitialContext lookup OrderEntry JMS QCF System out printIn StockDeliveryUpdateBean find QueueConnectionFactory end i Create a queue connection oQueueConnection oQueueConnectionFactory createQueueConnection oQueueConnection start Create a session oQueueSe
55. a half years of experience in developing and managing applications for the WebSphere Application Server You can contact Henning at Henning Burgmann de ibm com Cavin Edwards is a Solution Test Specialist from IBM UK based in Hursley He has nine years of experience in object oriented and client server computing He has worked in all areas of the software life cycle using languages and tools such as C Java and Delphi within OS 390 UNIX and PC environments For the last two years he has worked in the Hursley Solution Test Group with predominantly Java and Web based software for a variety of test and customer focused solutions His latest role includes Team Leading Solution Test EJB Interoperability Test and Performance Analysis You can contact him via e mail at cav_edwards uk ibm com Copyright IBM Corp 2002 ix Elena Lowery is a Software Engineer at IBM Rochester She currently works in the server Custom Technology Center where she designs and develops custom applications for IBM Customers and Business Partners She is a Sun Certified Java Programmer with four years of experience in object oriented programming and Java Her areas of expertise include Java WebSphere XML and Internet software development Elena can be contacted at eloweryGus ibm com Ruth Poole is a Software engineer with the iSeries Custom Technology Center She worked for several years writing code for the iSeries operating system She is a Sun Certified Java
56. another EJB the Internationalization service propagates all invocation context elements associated with the current thread on the outgoing requests If an invocation context element was set using the API the Internationalization service propagates the specified element Otherwise the Chapter 6 The Internationalization service 111 Internationalization service propagates the default element associated with the invoking the component s JVM at that time This is identical to CSI except that in SSI the invocation context is always that of the caller This management policy could be referred to as RunAsCaller DefaultToServer 6 3 Using the Internationalization service in the example application With the Internationalization service enabled on the server the HTTP client s context is propagated to the server when the client accesses OrderEntryServlet This context is then available to all components of the OrderEntry application To use the internationalization context we must gt Bind to the Internationalization service gt Use the UserInternationalization interface to retrieve API objects that afford access to the desired Internationalization context types gt Access the desired context type Once the context is accessed we can use it with time zone and locale sensitive operations 6 3 1 Binding to the Internationalization service Example 6 4 shows the ItemsViewBean constructor that binds to the Internationalizatio
57. application server that runs the OrderEntry application for example OrderEntryServer You have to add the system properties as shown in Figure 8 9 General Advanced File Transaction JVM Settings Services Custom System Properties Name value Add com ibm CORBA CommtTrace true com ibm CORBADebug fue r Advanced JVM Settings Generated Command Line Arguments Ocom tem CORBA CommTrace true Deor Tbm CORBA Debug true Apply Reset Help Figure 8 9 JVM settings for CORBA traces 186 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide These system properties activate the tracing for the Java ORB runtime Also you have to set the trace filter and the trace location by using the WebSphere Application Server trace service You achieve this by following these steps 1 Click the Services tab see Figure 8 9 2 Select the Trace Services line 3 Click Edit properties 4 For the Trace specification value add System0ut al 1 disabled ORBRas al 1 enabled 5 Select the Specify radio button in the Trace output file field 6 For the Trace output file or another output file value add WAS_HOME logs orb_defaultserver 1log 7 Click OK 8 Click Apply 9 Restart your application server Figure 8 10 shows the settings for the trace specification PEE General Node P23BK48D Application Server OrderEnt
58. available genies are cpp_poa_equal tcl cpp_poa_random tcl java_poa_random tcl cpp_poa_genie tcl idl2html tc1 list tcl cpp_poa_op tcl java_poa_genie tcl stats tcl cpp_poa_print tcl java_poa_print tcl vb_genie tcl We are using cpp_poa_genie tcl for creating our CORBA server and java_poa_genie tcl for creating a Java test client You can also use the toolkit to generate an HTML documentation of your IDLs This is done with the command idlgen idl2html tcl CreditInstitute id You find more about the code generation toolkit for Orbix 2000 V2 0 in the document http www iona com docs orbix2000 2 0 codegen html index htm1 Defining the IDL The starting point for the server development is to create the IDL file It shall represent an CreditInstitute object that offers the possibility to check the creditability of a customer The only method is isCreditableFor which takes a Person object and a double as input parameters It returns true or false and can throw two kinds of the CORBA UserExceptions exceptions See Example 8 9 for the details Example 8 9 The Creditinstitute interface module com module ibm module itso module roch module credit const string ROOT_IOR_FILENAME nameservice ior const string OE_NAMING DIR OrderEntry const string CREDIT_NAMING_ENTRY CreditInstitute Chapter 8 The CORBA services 191 struct Person string forename string lastname E exception PersonNotFound str
59. available to the rest of the application without having to explicitly include the request as a parameter 5 2 3 Accessing WorkArea To access WorkArea in other parts of the application we add a method to the ApplicationMgr and OrderEntryClerkBean classes to bind to the WorkArea facility This method uses the same Context that is used to bind to the OrderEntryClerk EJB Example 5 3 shows the method that binds to the WorkArea facility Example 5 3 Accessing WorkArea import com ibm websphere workarea import javax naming private UserWorkArea getWorkArea Context ctx UserWorkArea workArea null try workArea UserWorkArea ctx ookup java comp websphere UserWorkArea This exception indicates a problem binding to the facility catch NamingException e e printStackTrace return workArea Once we bind to the WorkArea facility the UserWorkArea object is used to access the WorkArea associated with the current thread There is no need to specify which WorkArea we want There can be only one WorkArea associated with a thread There is no way to access WorkArea associated with another thread 5 2 4 Using WorkArea To get information out of WorkArea use the get method with the name of the property you want to get Example 5 4 shows how to retrieve the customer information from WorkArea Chapter 5 The WorkArea service 95 Example 5 4 Retrieving values from WorkArea import com ibm websphere workarea
60. check if the administration server is running Chapter 8 The CORBA services 185 Enabling CORBA traces It is possible to enable CORBA traces on the client and the server side to see what data is really sent by the client or received by the server IBM client You have to set the following environment variables set SOMDCOMMDEBUGFLAG 259 set SOMDGETENV 1 You can simply delete the comment before those entries in the OE_HOME corbal client ibm2ejb set_ibm2ejb_env bat file and execute it on the command line It is best to redirect the output during execution of the client into a file because you get a large amount of trace output VisiBroker client Unfortunately it looks like there are no possibilities to set environment variables or properties to get trace output from a VisiBroker client It is possible for the VisiBroker daemons and for a server process but not for a client WebSphere Administration Server To get CORBA traces from the Administration Server you have to edit the file WAS_HOME bin admin config You have to add the following configuration parameters com ibm CORBA Debug true com ibm CORBA CommTrace true com ibm ejs sm adminServer traceString O0RBRas al 1 enabled com ibm ejs sm adminServer traceOutput WAS_HOME logs adminserver_orb log You can choose any location for the trace output file WebSphere default server In the WebSphere Administrative Console you have to change the JVM settings of the
61. committed or rolled back when a message bean completes its processing gt Processing incoming messages by invoking the onMessage method of the specified message bean To enable JMS Listener we have chosen the existing default Application Server in the topology However you can use any existing server to perform this exercise Then ensure it has the Extended Messaging Service enabled see Figure 4 15 1 Expanded Nodes gt lt local machine node gt gt Application Servers gt Default Server 2 Click the Custom tab in the server configuration pane 3 Select Extended Messaging Support 4 Click Edit Console View Tools Help ela o r x g amp 9 WebSphere Administrative Domain Virtual Hosts O Server Groups Installed Web Modules Nodes P23BK66H EHE Application Servers ore i i i i Custom BT inated Eo Madise General Advanced File Transaction JVM Settings Services Installed Web Modules E Generic Servers Add Enterprise Applications Edit Remove Service Enabled Automatic Generation of Plugin Configur True WorkArea Service True Internationalization Service True Extended Messaging Support Service True E Resources a Type Time Event Message Source Options 10 2 01 4 25 Console Ready 2 E y al Details xl Clear Figure 4 15 Ensuring an Appli
62. created from FindClass Dim clsPortRemObj As Object Dim oCustomerHome As Object oArgsb AddObject java lang Object oJavaObj oArgsb AddObject java lang Class oXJB FindClass com ibm itso roch wasaejb CustomerHome Set clsPortRemObj oXJB FindClass javax rmi PortableRemoteObject Set oCustomerHome clsPortRem0bj narrow oArgsb This is not the suggested approach and there is a good chance it will be deprecated in the next release The performance is very similar regardless of wether the client container is used The only difference is the time taken to launch and initialize the client container which is only a few seconds 130 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 7 4 3 Optimized container approach An alternative is to take a slimmed down version of the full EAR file that was deployed on the server and use that as the reference when launching the client container This approach would be used when the size of the whole EAR file would be an issue or when the whole EAR file contains secure information It is best to use the Application Assembly Tool AAT to remove unnecessary components such as WAR files By doing this the tool will also remove the components referenced in the deployment descriptors 7 4 4 Components of the client side EAR file In order for the ActiveX application to obtain the home interface of an EJB it needs the compiled EJB stubs on the classpath Generally the st
63. development environment on page 19 Chapter 3 The Business Rule Beans service 47 3 5 Implementing the CustomerClassification class Example 3 15 shows the complete implementation of the CustomerClassification class Example 3 15 Implementation of the CustomerClassfication class package rules import com ibm websphere brb RuleImplementor import com ibm websphere brb ConstraintReturn import com ibm websphere brb TriggerPoint import com ibm websphere brb BusinessRuleBeansException import com ibm websphere brb mgmt IRuleCopy import com ibm websphere brb implementor ImplementorHel per public class CustomerClassification implements RuleImplementor These variables are initialized in init int preferredLevel int goldLevel int platinumLevel set to true at the end of init boolean initialized false private final static String PREFERRED LEVEL Preferred private final static String GOLD LEVEL Gold private final static String PLATINUM_LEVEL Platinum public CustomerClassification super public Object fire TriggerPoint tp Object target IRuleCopy rule java lang Object parms throws BusinessRuleBeansException String classification null int amount 0 if initialized One parameter is expected the amount of customer purchases YTD ImplementorHelper assertParamLength parms 1 CustomerClassification fire amount Integer parms 0 intValue if amount
64. entire application is built by selecting Project Rebuild All This generates all the class files from the source code for the message bean including its stubs and RMI code All Java source for your EJB project can be found by expanding your EJB project in the Navigator view 13 Export the modified EAR file for the application and deploy it in WebSphere Application Server Enterprise Edition 4 2 7 Testing the JMS sample code To test the sample code we need to send a message to the JMS destination Qin We use the MQSeries Explorer to perform this task see Figure 4 20 1 Start the application server that hosts the OrderEntry application Start MQSeries Explorer Expand the Queue Manager tree Expand the local machine node Select Queues Right click the Qin queue and select Put Test Message N OOA W DB The message we place is a comma separated list of integers the factory ID stock ID and inventory level increase respectively for example 0001 000001 50 74 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide jm MQSeriesP2p Console Root IBM MQSeries Queue Managers p23bk66h Queut Console Window Help CD aw J Action View Favorites e mlm x 2 IEAM Eh Sit Tree Favorites Name Current Depth Queue Type Cluster Name C Console Root FI DEFAULT 0 Local IBM
65. f OrderEntryWeb folder Right click it and select Properties In the Properties window select Java Build Path Click the Libraries tab Click the Add External Jars button Navigate to WAS_HOME lib and select brbClient jar aswa jar i18nctx jar and ras jar Click OK in the Properties window to save the changes 4 Add aswa jar to Deployed_OrderEntryEJB project Right click Deployed_OrderEntryEJB Inthe Properties window select Java Build Path Click the Add External Jars button Navigate to WAS_HOME lib and select aswa jar a b c Click the Libraries tab d e f Click OK in the Properties window to save the changes g Atthis point you should see no error ignore warnings 5 Install the OrderEntry application in WebSphere Application Server Enterprise Edition a Export the OrderEntry project from Application Developer i From the Navigator View in WebSphere Studio Application Developer select OrderEntry folder Right click it and select Export EAR file ii Click the Browse button and navigate to OE_HOME iii Type the name of the EAR file which is OrderEntryWithBRBeans ear iv Select the Export source files box v Click Finish b From the WebSphere Administrative Console start the Install Enterprise Application Cc wizard Select the Install Application radio button d Select OE_HOME OrderEntryWithBRBeans ear Chapter 3 The Business Rule Beans service 21
66. gt Some data types are not supported gt The idl2cpp compiler does not support C namespaces properly To address the first two problems we had to 1 Copy the following files from the WebSphere EJB server to VisiBroker 4 1 C client sample Vtlib idl Vtlib_vb hh Vitlib_I_vb cpp 2 Delete all includes from the Customer id l CustomerKey id and CustomerHome id besides include orb idl 3 Add as replacement for the removed references immediately after the include of orb idl include Vtlib id1 4 Delete the raise of the exceptions javax ejb FinderEx and javax ejb CreateEx from the method declarations 5 Remove all Java modules from the three IDL files 178 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide OMG IDL to C language mapping specifies that each IDL module should be mapped to a C namespace with the same name If namespaces are not supported by the C compiler the modules can be mapped on classes But that means that several IDL files containing a module with the same name will generate C header files with different classes having the same name Therefore the solution for problem three is to 1 Merge the three IDL files to one file Customer_merged idl 2 Rename the IDL files to 1_Customer idl 2_CustomerKey idl and 3_CustomerHome idl to merge them in the right order 3 Create two empty files 1_Customer_c hh and 2_CustomerKey_c hh to
67. hashCode method was taken from the java lang string hashCode implementation in IBM s JDK 1 2 2 5 The CustomerKey objects are created by a factory This CustomerKey_factory class has to be defined in CustomerKey ih Add the factory class with the two creation and two standard methods class com_ibm_itso_roch_wasaejb CustomerKey_factory public com ibm itso roch wasaejb CustomerKey_init public create methods of the CustomerKey_init class in CustomerKey hh virtual com ibm itso roch wasaejb CustomerKey create_ virtual com ibm itso roch wasaejb CustomerKey create CORBA _WStringValue CORBA WStringValue key general methods virtual CORBA ValueBase create_for_unmarshal CORBA ValueBase asValueBase void v i Note The create methods can be copied from the CustomerKey_init class in CustomerKey hh 6 Add the implemenations of the factory class methods to CustomerKey_I cpp CORBA ValueBase com_ibm_itso_roch_wasaejb CustomerKey_factory create_for_unmarshal return new com_ibm_itso_roch_wasaejb_CustomerKey_Imp1 CustomerKey com_ibm_itso_roch_wasaejb_CustomerKey_factory create_ return new com_ibm_itso_roch_wasaejb_CustomerKey_Imp1 CustomerKey com_ibm_itso_roch_wasaejb_CustomerKey_factory create_CORBA_WStringValue CORBA WStringValue key Chapter 8 The CORBA services 175 CustomerKey ckey new com_ibm_itso_roch_wasaejb_CustomerK
68. in needless overhead Now that the JVM has been initialized the oXJB object can be used to access Java classes and objects 128 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 7 4 Using a J2EE client container Using a J2EE client container from within the attached JVM is optional but it does provide many benefits and is the preferred approach 7 4 1 Client container approach The standard approach to developing a standard J2EE client side application is to run the Java application inside a J2EE client container This provides gt A programming model on the client side that is consistent with the server side gt Enables easier lookup of EJBs and resources using the java comp style naming Example 7 2 shows how to lookup the home interface of the CustomerBean EJB when the client application runs inside a J2EE client container Example 7 2 Getting a reference to the CustomerHome Set oInitialContext oXJB NewInstance oXJB FindClass javax naming InitialContext Set oJava0bj oInitialContext lookup java comp env ejb CustomerBean Dim oArgsb As Object Set oArgsb oXJB GetArgsContainer Narrow it This is more EJB J2EE code Here we use JMethodArgs object to coerce our EJB object to a specific class In this case our EJB Home class Notice that we are calling the static narrow method on a Class Proxy object that was created from FindClass Dim clsPortRemObj As Object Dim oCustom
69. include directives from the generated Customer_merged_c hh The output of all these manual activities is the following five files in the directory OE_HOME corba client vb2ejb com ibm itso roch wasaejb 1_Customer idl 2_Customerkey idl 3_CustomerHome idl 1_Customer_c hh 2_CustomerKey_c hh YYYY Y Merging the IDL files The makefile utility automatically merges the IDL files The makefile utility merges the IDL files The output is Merging the Customer IDLs copy b com ibm itso roch wasaejb _Customer id Customer_merged id com ibm i tso roch wasaejb 1_Customer id com ibm itso roch wasaejb 2_CustomerKey id com ibm i tso roch wasaejb 3_CustomerHome id 1 file s copied Compiling the IDL files The client stub files are built from the merged IDL file In addition the IDL for the valuetypes has to be compiled Note that this is a different IDL compiler than the one that was used in Compiling the IDL files on page 166 The makefile utility generates the client stubs which produce the output Generating the Customer_merged client stubs idl2cpp I VBROKERDIR idl I src_suffix cpp export __declspec d1lexport Customer_merged id Warnings are ignored Generating the client stubs of the value type library idl2cpp I VBROKERDIR id I src_suffix cpp export __declspec dllexport Vtlib idl Warnings are ignored Note The export flag is important Otherwise the objects wo
70. is invoked on the server where the rule implementor is installed gt Anywhere The BRBeans framework first tries to fire the rule implementor locally If the rule implementor is not found the framework tries to fire it remotely Important We use the local firing location in the examples provided in this chapter If you install the OrderEntry sample application on the remote WebSphere server change the rule firing location to remote 3 2 3 Implementing a classifier rule We start the process of developing the business rules by defining a classifier rule that we will use in the OrderEntry application Classifier rule If a customer has purchased X dollars worth of products YTD then the customer qualifies for Y level We follow the general guideline defined in 3 2 2 General approach for implementing business rules on page 22 Creating a rule implementor class 1 Create a rule implementor see the complete class implementation in Example 3 15 on page 48 a In the Navigator view of WebSphere Studio Application Developer expand the OrderEntryWeb folder Select the source rules folder and right click Select New gt Other Select Java in the left pane of the pop up window and Java class in the right pane Type the name of the class which is CustomerClassification Click the Add button next to the Implements Interfaces box Select the Rulelmplementor interface Click Finish 2 Implement the Ru elmplementor met
71. levellDiscount The method can return 0 return new Integer discount Base rules configuration Start the Rule Management Application if it is not already started see 3 2 1 Setting up the development environment on page 19 Expand the Rule Namespace folder and select the DiscountRules folder You should see two CalculateDiscount rules as shown in Figure 3 10 Rule Browser E lol x File Edit View Help All Folders ANN Rule Namespace CustomerRules a OiscountRules H E OrderRules H E ShippingRules H E com Rules in folder DiscountRules Name a Status _ Start Date eb CalculateDiscount in effect 1 1 01 12 01 AM 4 9 CalculateDiscount in effect 1 1401 12 01 AM v 4 b Figure 3 10 Discount rules configuration 2 Rules Examine the properties of each rule 1 Select the rule and right click Select Properties 2 The General tab is identical for both rules Notice that the first radio button Rule is not classified and does not perform classification is selected All base rules must select this classification 3 Click the Implementation tab The rules have different implementation classes and different initialization parameters One rule specifies DiscountByLevel as the implementation class and the other one is DiscountByTotal 34 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Rule client implementation The next step is to implement the client
72. list see Figure 6 5 8 Right click I118nContextlmpl and select All from the pop up menu The icon to the left of I1118nContextImpl will change from gray to blue yellow red to indicate the trace has been selected see Figure 6 5 gi Trace x Ring buffer size f thousand entries Dump file name Dump Components ConfigError ORBRas SystemOut com ibm lApplicationContext lApplicationContextimpl Sm Bil 8nContextimpl PE CurrentCreator FI Currentimp HE LocalThreadContext Il Messages Hl Requestinterceptor Hl Service Pi ThreadContextManager HE util HI Locale FI LocaleList TI TimeZone x Cancel Reset Help Figure 6 5 Trace dialog with I118nContextlmpl trace selected 9 Repeat steps 7 and 8 for the com ibm ws i18n context package see Figure 6 6 Ring buffer size fi thousand entries eu file name f guna ibm lApplicationContext lApplicationContextimpl HE 111 8nContextimp cmm ejs websphere E ws TEPER RER ag classloader eex Hh itn com Bcontend naming pmi runtime security threadContext util wim Cancel Reset Help 1 Figure 6 6 Trace dialog with com ibm ws i18n context trace selected UHH ee Chapter 6 The Internationalization service 119 10 Click OK in the Trace dialog The
73. of IBM s intellectual property rights may be used instead of the IBM product program or service Information in this book was developed in conjunction with use of the equipment specified and is limited in application to those specific hardware and software products and levels IBM may have patents or pending patent applications covering subject matter in this document The furnishing of this document does not give you any license to these patents You can send license inquiries in writing to the IBM Director of Licensing IBM Corporation North Castle Drive Armonk NY 10504 1785 Licensees of this program who wish to have information about it for the purpose of enabling i the exchange of information between independently created programs and other programs including this one and ii the mutual use of the information which has been exchanged should contact IBM Corporation Dept 600A Mail Drop 1329 Somers NY 10589 USA Such information may be available subject to appropriate terms and conditions including in some cases payment of a fee The information contained in this document has not been submitted to any formal IBM test and is distributed AS IS The use of this information or the implementation of any of these techniques is a customer responsibility and depends on the customer s ability to evaluate and integrate them into the customer s operational environment While each item may have been reviewed by IBM for accuracy in a sp
74. of the disparate application within a company is the most critical problem that the majority of enterprises face these days With J2EE Connector Architecture included in WebSphere Application Server Advanced Edition and WebSphere Enterprise Services the enterprises get the runtime platform with the widest selection of connectors and integration services available on the market today Internationalization service is beneficial to the companies operating in the global environment WebSphere Application Server Enterprise Edition sends transparently to an application the locale and time zone information from the client to the application server Finally the business process management capabilities of BPBeans give the enterprises a powerful tool to gt Overcome the problems with frequent changes to an application gt Provide a rollback capability at the business process level gt Create an outcome based application Each of the WebSphere Enterprise Services is covered in more detail in the following chapters Chapter 3 The Business Rule Beans service on page 15 Chapter 4 Extended Messaging Service on page 51 Chapter 5 The WorkArea service on page 91 Chapter 6 The Internationalization service on page 105 Chapter 7 The ActiveX bridge service on page 121 Chapter 8 The CORBA services on page 153 Chapter 9 The Business Process Beans service on page 209 vvvvvvy 4 WebSphere Applica
75. or transaction context in WebSphere Application Server It provides the following services to a BPBeans component gt Manages a component s life cycle gt Manages the context properties gt Monitors a component s status The runtime environment starts and stops the BPBeans components through the context object The context properties are name value pairs These properties are set either during the modeling of an application in the ABC tool or at the runtime by the BPBeans runtime The monitoring service provides the way to access the current state of a BPBeans component It also provides the way to view and record the debugging information The BPBeans framework provides several specialized context components Activity context Resource context Outcome decider context Process context JavaBean context YYYY Y Any BPBean components have to be wrapped inside a corresponding context in order to participate in the BPBeans model The word wrapped comes from the terminology used in the BPBeans framework Another way to look at the same concept is to realize that each component has to have an association with a context object As we discussed earlier a context object provides some services to a BPBeans component For example Activity Context performs the following actions gt Gets a port for Activity gt Publishes the outcome of Activity so that it is available to other BPBeans components gt Gets a Resource component used b
76. out print n Constructing name entry NameComponent nameArray ClientOrb stringToName nameEntry System out printIn Resolving name entry nameEntry 3 instObj rootContext resolve nameArray public static NameComponent stringToName String nameString System out printIn Creating NameComponent for nameString StringTokenizer tok new StringTokenizer nameString int partNo tok countTokens NameComponent name new NameComponent partNo for int i 0 i lt partNo i if tok hasMoreElements String token tok nextToken name i new NameComponent token else System err printIn Token not found return name After that the wrapper is ready to be used by the ApplicationManager object 8 4 3 Problem determination The two major building blocks for problem determination are checking the namespace and the additional CORBA communication debug output Checking the namespace As we mentioned in Configuring Orbix on page 188 the Orbix administration tool is itadmin You can either use itadmin as command line utility or as command shell The general usage is itadmin lt object gt lt method gt lt parameters gt The object that represents the namespace is ns You can execute the following commands 1 Geta listing of the namespace itadmin ns list 2 Geta listing of the OrderEntry naming context itadmin ns list OrderEntry 3 Resolve the binding to
77. passed from the client thread to the server However WorkArea is not transferred to new threads spawned from the thread that WorkArea is associated with For this reason WorkArea must be used cautiously in applications that use the Java Abstract Windowing Toolkit AWT The AWT implementation is multithreaded and WorkArea begun on one thread is not available on another For example if a program begins WorkArea in response to an AWT event such as pressing a button WorkArea may not be available to any other part of the application after the execution of the event completes 5 2 Using WorkArea in the example application In the example application we use WorkArea to pass information between the different parts of the application without having to explicitly pass a parameter We could just use the request object to pass the information but we would have to explicitly pass the request object when it is used outside the service method of the servlet This can be cumbersome since there is much more information in the request than we need It can also lead to errors that are hard to find since there is no mechanism to prevent changing the properties in the request object To use WorkArea we must perform the following actions in the application 1 Bind to the WorkArea facility This is done using JNDI Once we bind a com ibm websphere workarea UserWorkArea object to the facility this same object can be used to access many WorkAreas The actual Wor
78. result of the properties mentioned above it is important to use a different archive directory for every EAR file referenced on the client workstation 7 8 Modifying the EAR file for the ActiveX J2EE client container In the standard J2EE client application model the client code is contained in the Enterprise Application File EAR file as a JAR file The same EAR file can then be deployed on the server and the client Although different components are used by the client and the server it makes sense to package everything together When the client application is launched in a client container the application is given access to the resources required by the application including the EJB stubs In the case where the client application is an ActiveX component there is no Java code needed for the client application However in order for the client container to be launched inside the JVM the client container needs to know the name and location of the client application JAR file For this reason a dummy client JAR needs to be created 7 8 1 Setting up the Main class The client container not only needs to know the name and location of the dummy client JAR it also mandates that the client JAR s configuration includes the name of the first class to be called when the client container is launched This class is referred to as the Main class it contains the main method which is invoked by the client container Since the client JAR c
79. rules The tool allows you to explore and modify BRBeans rule configuration data rule name implementation class start and end date initialization parameters and others 16 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide gt BRBeans Rule Management APIs can be used by developers to build custom rule management applications for use by domain experts gt BRBeans Rule Importer and Exporter tool allows you to import and export BRBeans rule configurations as XML files This tool is similar to WebSphere s XMLConfig tool it can be used to move BRBeans rule configurations between servers The described components are used both during the development phase and at runtime Three activities take place during the development process see Figure 3 1 gt Rule implementors are created This step is optional Application developers can use BRBeans rule implementors provided with the framework gt Trigger points are placed in the rule client gt Business rules are configured in the Rule Management Application The tool uses BRBeans EJBs to save BRBeans rule configuration information This condition implies that an application server must be started prior to using the tool Place the Configure the Implement trigger point BRBeans rule business logic x ie Rule Management Application Rule Client Save configuraton EJB data SaM i BRBeans EJBs Java Class 7 UCENE a Figure 3 1 BRB
80. service in the OrderEntry application Rather we discuss the design and development steps in creating such a solution The following topics are discussed BPBeans basics BPBeans programming model BPBeans development Potential usage of the BPBeans service in the OrderEntry application YYY Yy Note To understand the structure of the OrderEntry application and to run it read the instructions in Appendix A Downloading and installing the OrderEntry application on page 221 Copyright IBM Corp 2002 209 9 1 BPBeans basics 210 BPBeans framework is a new technology that provides the advanced functionality to extend the J2EE programming model There are three main directions in which the BPBeans service expands the J2EE model gt It supports long running or extended business transactions These long running business transactions include multiple J2EE transactions This approach allows a more flexible and more sophisticated Enterprise Application Integration EAI solutions to be developed than would be possible by using the J2EE model alone gt It provides a compensation mechanism The J2EE model operates only on the traditional ACID transactions ACID transactions use a simple model where the resources can be locked for the duration of a transaction This requires the transactions to be small and fast to avoid holding those resource locks for significant periods of time The advantage of having a long running transac
81. the BRBeans rules 1 0 eee 228 Running the OrderEntry application 0 0 eee 229 ActiveX application client specific instructions 0 0 0 e ee eee 229 Appendix B Additional material 00 0 eee ee 231 Locating the Web material 0 0 0 cc eee 231 Using the Web materal recreos t PERENE EREET te teens 231 System requirements for downloading the Web material 231 How to use the Web material 0 000 cece eee 232 Related publications i 2 c e5 sgh 4d oh aR Eh be eee a eee ae 233 IBM REdDOOKS a h die dalieredim ace re atea ed hath wed oad ede eda ta neat 233 OtherireSOUlCES 2 3 Gi ae ck Pa eas St Gee Ors Sat at E Ta eek ed 233 Referenced Web sites ic5 ccc recede sinae e EEE wepabe donee ECERAN EEA 233 How to get IBM Redbooks ridade eee eae 234 IBM Redbooks collections 000 cece eae 234 Idex Se ani ark besa be fa ea ME a a bla Ee baS eae eae Ware ed eae tg ates 235 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Special notices References in this publication to IBM products programs or services do not imply that IBM intends to make these available in all countries in which IBM operates Any reference to an IBM product program or service is not intended to state or imply that only IBM s product program or service may be used Any functionally equivalent program that does not infringe any
82. the Java test client as described in Building the test client on page 200 Modifying the generated server sources You can compile and run the generated sources without any changes We did only some minor changes to the server main and the interface implementation The makefile copies over the two edited files The output is shown here Copy over the completed server files copy y srv completed server cxx srv 1 file s copied copy y srv completed com_ibm_itso_roch_credit_CreditInstituteImp cxx srv 1 file s copied In the files that are copied over we changed gt In server cxx The name of the server entry in the namespace The root IOR of the namespace is written to a file gt In com_ibm_itso_roch_credit_CreditInstituteImpl cxx In the algorithm for the random answers we reduced the frequency how often the two exceptions are thrown and added and more meaningful exception text Compiling the server code idlgen creates a makefile that is used for the compilation of the server code gt The IDL compilation produces the following output Compiling the server sources cd srv nmake nologo f Makefile server exe lt orbix_home gt orbix_art 2 0 bin idl base poa I lt orbix_home gt orbix_art 2 0 id1 F Henning oe corba server ejb2orbix CreditInstitute idl gt The output from the creation of the object files is if exist server obj del server obj cl c I lt orbix_home gt orbix_art 2
83. the bridge and demonstrates the option of connecting to the EJB container via a client container or straight from the JVM Client ActiveX Process VB MTS ASP Se rver EJBContainer RMIAIOP RMI IIOP Java Mail JAF J2EE Server Core XJB JClassFactory Figure 7 1 Positioning the ActiveX bridge The ActiveX bridge consists of a C DLL that calls some Java code using Java Native Interface JNI Figure 7 2 The Java code then invokes the services of either a J2EE client container or a Java proxy which in turn makes a call to a Java ORB 122 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Client App VB MTS ASP Activex C DLL O ActiveX Bridge e ActiveX Bridge Java Figure 7 2 Components of the ActiveX bridge The bridge also enables connection to J2EE APIs such as Java Naming and Directory Interface JNDI Java Database Connectivity JDBC Java Messaging Service JMS and Java Mail and URLs The bridge supports both workload management and security All exceptions thrown in Java code are encapsulated and rethrown as a COM error from which the ActiveX program can determine the actual Java exceptions The ActiveX to EJB bridge supports both free threaded and apartment threaded access and implements the Free Threaded Marshaler to work in a hybrid environment such a
84. the home interface methods is supported Chapter 8 The CORBA services 161 This restriction is derived from the assumption that session beans contain the majority of the business logic and coordinate access to the entity beans which mostly just provide an object oriented wrapper for a database table or other persistent store If you follow the best practices and implement your business logic in the session beans you won t need to access an entity bean directly The support for entity beans includes Creating a bean Finding a single bean Calling a business method Using client coordinated transactions for accessing TX_MANDATORY entity beans YYY Yy In general the EJB specification 1 1 allows you to return either a single object of your bean class or a collection The restriction is that you are only able to find single objects You cannot return the collections Since session beans don t have finder methods this restriction doesn t apply to them 8 2 3 C CORBA software development kit SDK The C CORBA SDK is a toolkit that allows you to create the WebSphere Application Server CORBA C clients and servers that can support interoperability as described in 8 2 1 WebSphere Application Server support scenarios on page 159 The SDK conforms to the CORBA 2 1 specification The WebSphere Application Server ORB runtime is a collection of several libraries and processes Some of the processes are C daemons and ot
85. the step 7 on page 217 as itis specified in the application model 6 To invoke a BPBeans application you need to create the com ibm bpb client local LocalClientContext object You specify three parameters that identify the application In the technology preview a BPBeans application has to be located on the same system as your client code The client code also directly accesses the file system These limitations should be removed in the production version of the BPBeans service 7 By invoking this method on the LocalClientContext object we request the Outln Port object It will be used to send a message to the application 8 We construct the message that will be sent to the application In the BPBeans framework we highly recommend that you create a message class either by implementing the com ibm bpbeans Message or com ibm bpbeans ClientMessage interface or by extending the com ibm bpb base MessageBase class Chapter 9 The Business Process Beans service 219 9 Senda message to the application The method returns an object that implements the com ibm bpbeans ResponseToken interface This interface has a method that allows any object that implements ResponseListener interface to register with ResponseToken 10 Register the OrderEntryClerkBean object as ResponseListener with ResponseToken 11 This method is part of the com ibm bpbeans ResponseListener interface 12 This method is part of the com ibm bpbeans
86. to develop a Visual Basic program using the ActiveX bridge service The topics that are covered include Initializing the JVM Using a J2EE client container Accessing Java objects methods and fields Handling the errors YYY Yy 7 3 Initializing the JVM The ActiveX client can create a JVM within its own process by calling the XJBInit method on a JClassFactory object The XJBInit method takes an array of Strings as a parameter This array of strings contain the same parameters that would be used when calling a Java program listed between Java and the name of the class Example 7 1 shows how to initialize a simple JVM in a Visual Basic application Example 7 1 Initialization of a simple JVM from a Visual Basic application Dim oXJB as Object Set oXJB createObject XJB JClassFactory Dim astrJavaInitProps 0 as String astrdavalInitProps 0 Djava class path c myjavaclasses oXJB XJBInit astrJavalInitProps In the Order Entry Client the code is in the XJBInit method of the ActiveX_XJBHelpers module As a result of current restrictions on JNI the JVM can t be unloaded It is there for the life of the ActiveX process Since it can only be one JVM there should only be one oXJB object Storing it globally gives easy access to the JVM from any method There is no harm in calling the code in Example 7 1 more than once but it only serves to create a new XJB JClassFactory with a connection to the same JVM resulting
87. uses Outln Port first it send a message and second it waits for response The ResponseListener interface declares two methods that are used by the BPBeans runtime to notify the listener when a response comes 2 One of the limitations in the BPBeans service in WebSphere Application Server Enterprise Edition Version 4 0 is that it doesn t have a synchronous mechanism to send and receive message between an application client and a BPBeans application For this reason we use a Java object to lock and wait for the response from the application However even this solution has a problem In those environments where BPBeans can create threads which might actually include the WebSphere Application Server EJB container the call back is made by BPBeans on a thread created by BPBeans and therefore not on the thread blocked by the wait call These limitations should be removed in the production version of the BPBeans service 3 This String represents the location of the application model file The file is created by the ABC tool and will be in the repository subdirectory of the tool The file will have the same name as the application but with Application xmi appended to the end of the name If you exported your application this parameter should specify the location of a JAR file 4 This String defines the name of the BPBeans application as it is specified in the application model 5 This String defines the name of Client Type created in
88. 0 cxx include Zi nologo GR GX W3 Zm200 MD Foserver obj server cxx server CXxx if exist CreditInstituteC obj del CreditInstituteC obj Chapter 8 The CORBA services 193 cl c I lt orbix_home gt orbix_art 2 0 cxx include Zi nologo GR GX W3 Zm200 MD FoCreditInstituteC obj CreditInstituteC cxx CreditInstituteC cxx if exist it_random_funcs obj del it_random_funcs obj cl c I lt orbix_home gt orbix_art 2 0 cxx include Zi nologo GR GX W3 Zm200 MD Foit_random_funcs obj it_random_funcs cxx it_random_funcs cxx if exist it_print_funcs obj del it_print_funcs obj cl c I lt orbix_home gt orbix_art 2 0 cxx include Zi nologo GR GX W3 Zm200 MD Foit_print_funcs obj it_print_funcs cxx jt_print_funcs cxx if exist CreditInstituteS obj del CreditInstituteS obj cl c I lt orbix_home gt orbix_art 2 0 cxx include Zi nologo GR GX W3 Zm200 MD FoCreditInstituteS obj CreditInstituteS cxx CreditInstituteS cxx if exist com_ibm_itso_roch_credit_CreditInstituteImp obj del com_ibm_itso_roch_credit_CreditInstituteImp obj cl c I lt orbix_home gt orbix_art 2 0 cxx include Zi nologo GR GX W3 Zm200 MD Focom_ibm_itso_roch_credit_CreditInstituteImpl obj com_ibm_itso_roch_credit_CreditInstituteImp cxx com_ibm_itso_roch_credit_CreditInstituteImp cxx if exist it_servant_base_overrides obj del it_servant_base_overrides obj cl c I lt orbix_home gt orbix_art 2 0 cxx include Zi nologo GR GX W3
89. 1 Note that the CustomerKey valuetype class has been compiled and linked as well in the last two steps The description of how to create this class is provided in Building the CustomerKey valuetype on page 174 Building the tools library The tools library consists of some classes that are used from both client implementations These classes provide trace and error handling utilities and include the MyOrb class which encapsulates the access to the ORB Also it includes two wrapper classes for the Customer and the CustomerHome class which hide the CORBA handling The creation of the tools library is done with a separate makefile called makefile tools It inherits its parameter settings from makefile ibm2ejb makefile tools is called by makefile ibm2ejb It executes the following steps Chapter 8 The CORBA services 167 1 Compile the tools classes The output is set INCLUDES 1 0E_HOME corba client ibm2ejb 1 0E_HOME corba tools 1 WAS_HOME Enterprise include I include set CC_FLAGS GX c nologo MD Od DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE DUSE_JAVA_EX DORB WebSphere set LIBS LIBPATH 0E_HOME corba client ibm2ejb LIBPATH 0E_HOME corba tools LIBPATH WAS_HOME Enterprise lib LIBPATH MSVCDir lib set LD_FLAGS NOLOGO INCREMENTAL NO DEBUG LIBPATH 0E_HOME corba client ibm2ejb LIBPATH 0E_HOME corba tools LIBPATH WAS_HOME Enterprise lib LIBPATH MSVCDir lib somororm 1ib somosalm Jib Vtlib lib kernel32 1l
90. 1 Visual Basic guidelineS 0 0 0 eee 144 7 7 2 Active Server Pages guidelines 0 c eee eee 145 7 7 3 Client container guidelines 0 0 cece eee 147 7 8 Modifying the EAR file for the ActiveX J2EE client container 148 7 8 1 Setting up the Main class 1 0 ce eae 148 7 8 2 Creating the dummy client JAR 00 00 naaa 149 7 8 3 Adding the EJB references 0 c eect tees 150 7 8 4 Optimizing the EAR file 2 2 2 eee 151 Chapter 8 The CORBA services 0 c cette 153 8 1 Positioning of CORBA ororena etu ra CA e a E A eee 154 8 1 1 Role of CORBA in J2EE 6 tee 157 8 2 Overview of WebSphere Application Server Enterprise Edition CORBA support 159 8 2 1 WebSphere Application Server support scenarios 00 0 eae 159 8 2 2 Interoperability with an EJB 2 ee 161 8 2 3 C CORBA software development kit SDK 00 00a eee 162 8 3 C CORBA clients for the OrderEntry application 0 0 eee eee 163 8 3 1 Configuring the environment 0 0 cee eee 163 8 3 2 IBM client of the Customer EJB 0 0 0 ee ee 164 8 3 3 VisiBroker client of the Customer EJB 0 0 00 eee 177 8 3 4 Problem determination i lt srsirirsetritpri vrat itk eee 185 8 4 Connecting OrderEntry application to C CORBA server 0 055 187 8 4 1 Configuring the environment 00 00 cee ee 188 Conte
91. 102 CORBA considerations 102 creating 94 creating and populating 94 key value mode triplet 92 Index 239 nested 92 97 99 100 passing WorkArea through multiple WebSphere Appli cation Servers 104 property modes 97 putting other objects 102 scope 92 terminating 96 terminating nested WorkArea 100 the UserWorkArea interface 101 using 95 using in the example application 93 WorkArea service 91 wsqcf 85 wstcf 85 X XML configuration file 60 65 81 240 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide WebSphere Application Server Enterprise Edition 4 0 0 5 spine 0 475 lt gt 0 873 Redbooks 250 lt gt 459 pages WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The ultimate reference to WebSphere Enterprise Services Programming examples of Enterprise Services usage Tips and techniques from the developers With the advent of Java 2 Platform Enterprise Edition J2EE application servers companies are beginning to adopt the programming model that offers new levels of portability flexibility reuse and scalability Complementing J2EE technology the emerging set of Web services standards arms companies with even greater business flexibility to compete in a changing world The most sophisticated e businesses however need to extend these industry standards to meet important enterprise requirements In respons
92. 16 3141 Benefits ki aruia naa eed la hada ee RPE eRe ee eR ee A 16 3 1 2 BRBeans framework components auaa naaa 16 3 1 3 Identifying business rules 0 0 eee 18 3 2 Implementing business rules with the BRBeans framework 18 3 2 1 Setting up the development environment 00 0 cece eee 19 3 2 2 General approach for implementing business rules 200 55 22 3 2 3 Implementing a classifier rule 2 0 0 ee eee 26 3 2 4 Implementing base ruleS 0 0 ce eae 32 3 2 5 Implementing a business rule with dependent rules 41 3 3 Performance considerations a a uaaa aaa aaea 46 3 4 Deployments aoa eeeties p e hh leare OM Ma EE eae ate EE ie 47 3 5 Implementing the CustomerClassification class 000 ce eee ees 48 Chapter 4 Extended Messaging Service 0 0 c eee eee eee 51 4 1 An overview of basic JMS and JMS Listener 00 0 eee 52 4 2 Configuring JMS point to point for the OrderEntry application 53 4 2 1 The core components of JMS point to point a na saaa 0 00 ee eee 54 4 2 2 Defining physical queues 20 ee eee 55 4 2 3 Defining JMS resources 0 cette ee 55 4 2 4 WebSphere Application Server 0 eee 60 4 2 5 JMS Listener XML configuration file 0 0 00 cee eee eee 65 4 2 6 The MESSAGe DOAN 2 Sissi ae rie 2a Aleta a etn ea le a EE Seb ia le at
93. 71 General Internal Failure Internal Failure In Visual Basic and VBScript the COM error numbers are converted to 2 byte longs stored in the Err Number field The values of these longs are the decimal representation of originating COM Hex value For example for Java exceptions 0x6003 becomes 6 x16 x16 x16 3 24597 Other languages may use more memory to store this 2 byte Hex value changing its decimal representation In the OrderEntry application errors are handled in two ways The If statement determines if an error message should be displayed to the user In the example shown in Example 7 14 an error message needs to be displayed if the Customer ID doesn t exist in the database If this event occurs a javax ejb FinderException exception is thrown with reference to the Customer EJB ErrorHand er first uses the value 24597 to identify a Java exception and then the key words FinderException and CustomerBean to identify that the exception was caused by an invalid Customer ID The code could also compare Err Number to amp H6003 Example 7 14 GetCustomer function in COrderClerk cls Public Function GetCustomer ByVal CustomerID _ As Object On Error GoTo ErrorHandler ErrorHandler If Err Number 24597 Then If InStr Err Description CustomerBean gt 0 And _ InStr Err Description javax ejb FinderException gt 0 Then RaiseEvent CustomerError Errors ERRID_NO_RECORD_ FOUND End If 142 WebSphere Appli
94. A C SDK sample called C Client that uses valuetypes sample which is shipped with WebSphere Application Server You find the description of all examples in the file YWAS_HOME Enterprise samples index htm file We go through the following basic steps which are discussed as subsections Set up the environment Build the client Run the client Build the CustomerKey valuetype Use the CustomerKey valuetype Sik Oe The last two subsections discuss how to create your own valuetype They are separated from the Build the client and Run the client because of the complexity and importance of these tasks Setting up the environment To set up the needed environment variables for building and running the client you have to start a command prompt and execute 0E_HOME corba client ibm2ejb set_ibm2ejb_env bat Before you start the client you have to edit the following properties file that sets parameters for the WebSphere Application Server ORB runtime 0E_HOME corba client ibm2ejb ibm2ejb props The value for nameServerHost must match your system s name including domain name com ibm CORBA nameServerHost lt hos tname gt The settings in this property file assume that your system is set up with American English as the default language If you are using a different default language you may have to use different values for the settings For further details see the documentation of the C Client th
95. A Programmer s Guide Handling requests The implementation of the CreditInstitute interface is done by the class com_ibm_itso_roch credit_CreditInstituteImp1 If a method request comes in to the ORB it is forwarded to that class Example 8 16 shows how the isCreditableFor method is implemented Example 8 16 Handling requests CORBA Boolean com_ibm_itso_roch_credit_CreditInstituteImp1 isCreditableFor const com ibm itso roch credit Person amp pers CORBA Double pay IT_THROW_DECL CORBA SystemException com ibm itso roch credit PersonNotFound com ibm itso roch credit InformationConfidential cout lt lt com_ibm_itso_roch_credit_CreditInstituteImp isCreditableFor called lt lt endl CORBA Boolean _result _result global_random gt get_boolean Decide if we want to throw back an exception switch global_random gt get_range 10 case 1 com ibm itso roch credit PersonNotFound IT_ex No person with the given lastname found throw IT_ex case 2 com ibm itso roch credit InformationConfidential IT_ex Even the reason is confidential throw IT_ex default Don t throw an exception break return _result The global_random class is a helper class that is created by genie for creating random values get_boolean delivers a true value with a probability of 50 An exception is thrown with a probability of 20 If
96. BRBeans product documentation at http www ibm com software webservers appserv doc v40 aee index html BRBeans rule states BRBeans rule state determines weather a rule can be used by the rule client at runtime A BRBeans rule can be in one of five states gt In effect The BRBeans rule is active start date is before the current date and time and the end date is either blank or after the current date and time and is available for use BRBeans rules must be in this state in order to be fired from the rule client Scheduled BRBeans rule start date is set to some date in the future Expired The BRBeans rule is no longer active rule end date is in the past Invalid The BRBeans rule configuration has errors Unavailable The BRBeans rule is not ready for use Rule states can be modified in the Rule Management Application Chapter 3 The Business Rule Beans service 25 Note For more details on changing a rule state see the BRBeans product documentation at http www ibm com software webservers appserv doc v40 aee index html BRBeans rule firing locations The firing location determines where the rule implementor is instantiated and invoked The firing location is specified in the Rule Management Application Implementation tab of the Properties window There are three possible values for the firing location gt Local The rule implementor is fired in the same JVM as the rule client gt Remote The rule implementor
97. Customers can be selected by entering their customer ID or performing a customer search to list all the customers in the database Once the customer has been chosen the items for order are selected in a similar manner either by Item ID or following an Item search that displays all the Items in the database Choosing the quantity and pressing the Tab key highlights the Add Item button Once enough items are selected the order can be processed This returns the order number Figure 7 4 shows an example of the clients main window gt Order Entry using Jaya COM a x Fie Search Item Process Order r Customer Information Customer ID 0005 Name Gary C Mullen Schultz Street 5th Avenue 55 City State Minneapolis Mn Zip Code 19100 2010 r Item Information ltem Description Quantity 00001 3 Doll_House_Furniture 3 __Price Extended 000005 Twelye_Num_Two_Pencils 2 50 58 101 16 000001 WEBSPHERE REDBOOK 1 30 00 30 00 a Enter quantity then tab to Add item button Figure 7 4 The Order Entry Client that uses the ActiveX to EJB bridge 7 2 3 Installing the client application After installing the WebSphere Application Client and ActiveX bridge service place the OE_HOME Activex OrderEntry ear file in the directory WAS_HOME WSsamples Client J2EE OrderEntry Here WAS_HOME for example C IBM WebSphere AppClient is the environment property set up when installing the We
98. Developer and currently assists iSeries customers in developing and deploying applications You can contact Ruth via e mail at rjpoole us ibm com Many thanks to the following people for their contributions to this project Debasish Banerjee Karri Carlson Sharad Cocasse Logan Colby Eric Herness Chris D Johnson Frank Malin Tom Musta Jon K Peterson Anh khoa D Phan Dianne Richards Ray V Scott Rohit Singh Scott Waldner Al White David Zavala IBM Rochester Minnesota Lou Degenaro IBM Watson Research Center NY Phil Adams John Alcorn Mark Coats Stephen Cocks Donavon Johnson Richard Mills Galen Young IBM Austin TX Krishna Byri Hailong Mao Heather Phung Richard A Sitze Ray Stutzman IBM Charlotte NC Kyoko Hamada IBM Mountain View CA x WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Tracy Gardner Vernon Green Catherine Griffin Dave Vines IBM Hursley United Kingdom of Great Britain and Northern Ireland Special notice This publication is intended to help the developers to create Web applications for WebSphere Application Server Enterprise Edition using WebSphere Enterprise Services The information in this publication is not intended as the complete specification of any programming interfaces that are provided by WebSphere Application Server Enterprise Edition Version 4 0 See the PUBLICATIONS section of the IBM Programming Announcement for WebSphere Application Server Enter
99. Driver Files E l0 x Specify the path to the implementation files for this provider CABMMOSeries Java libifscontext jar Add Driver CMBMIMQSeries Javailib providerutil jar Remove Figure 4 11 Configuring the JMS Provider J NDI entries For each resource declared using the JMSAdmin tool we define a corresponding JNDI entry within WebSphere Application Server Figure 4 12 shows the JMS destination queue called Qin and an output queue Qout We define these JNDI entries by using these steps iP 2 3 4 Specify the JMS destination Name and its External JNDI Path Expand the Resources gt JMS Providers gt MQSeries nodes within the administrator console Right click JMS Destinations Select New Chapter 4 Extended Messaging Service 61 Console View Tools Help eleev xa amp og WebSphere Administrative Domain Description JMS Provider Virtual Hosts EB Qin IBM MQSeries i Server Groups IBM MQSeries Nodes Enterprise Applications P23BK66H_sampleApp Resources General JDBC Providers E JavaMail Sessions Name Qin URL Providers E J2C Resource Adapters External JNDI path OrderEntryiJMS ain JMS Providers Description E IBM Maseries E JMS Connection Factories fay JMS Provider IBM MQSeries Apply Reset Help Type Time Event Message So
100. EAR file Browse to 0E_HOME OrderEntryWithoutBRBeans ear Type the name of the project which is OrderEntry Click Finish 2 Add the BRBeans JAR file to the OrderEntry EAR project Note You can perform this step using the WebSphere Application Assembly tool In WebSphere Studio Application Developer select the OrderEntry project Click File gt Import Double click the EJB JAR file Browse to WAS_HOME Enterprise BRBeans and select BRBeansDB2 jar Type the name of the EJB project which is BRBeans Click Finish In the task window you can see a number of errors caused by BRBeans missing references We need to add two JAR files to BRBeans EJB project classpath i Open the J2EE Perspective click Perspective gt Open gt J2EE ii Click the Navigator tab ii Right click the BRBeans folder and select Properties iv In the Properties window select Java Build Path v Click the Libraries tab vi Click the Add External Jars button vii Navigate to WAS_HOME lib viii Select brbClient jar and brbServer jar ix Click OK to save the properties x In the Navigator view right click the BRBeans folder and select Rebuild project Add BRBeans EJBs references to the OrderEntryWeb module i In WebSphere Studio Application Developer open the J2EE Perspective select Perspective gt Open gt J2EE ii Click the J2EE View tab iii Expand the Web Modules folder iv Double click OrderEntryWeb
101. Edition 4 0 A Programmer s Guide WebSphere Application Server topic of JMS Message Business Logic MQ Client gt gt S gt Q HA Broken Listener Bean D gt Bean gt Q Application interest default queue V Figure 4 22 The JMS publish subscribe model The architecture for publish subscribe differs from the point to point model in several key aspects These are discussed in the following section 4 3 1 The core components of JMS publish subscribe There are five core components for the JMS publish subscribe model as shown in Figure 4 23 JMSAdmin WebSphere Application Server JMS resource definitions h destination JNDI context Naming server to enable lookup topics topic connection JMS Listener factory are defined and All JMS resources message beans given a JNDI path have a corresponding JNDI entry in WebSphere MQ provides JMS Listener is physical queues configured from an and broker XML file JMS Provider MQSeries XML Configuration File JMS Listener configuration MQSeries Default message Queue broker Figure 4 23 The core components of JMS in the publish subscribe model The JMSAdmin tool is used to declare topics rather than queues The MQSeries message broker is used to enable publish subscribe WebSphere Application Server is now used as a JNDI server for topic JMS resources The XML configuration file links message beans to the corresponding JMS Listen
102. H E installedConnectors E QO java HS lib f logs x Type PROPERTIES File Size 105 bytes 105 bytes Figure A 3 Locating the OrderResourceBundle properties file a OrderResourceBundle properties 8 SearchCatalog jsp Local intranet Follow these steps to install the OrderEntry application Note If you plan to go through the BRBeans development process you don t have to install the OrderEntry application at this time Skip the rest of this appendix Start the Install Enterprise Application wizard from the Administrative Console In the pop up window make sure you select the Install Application ear option Navigate to the OE_HOME OrderEntry ear file and select it Go through the wizard until you reach the Selecting Application Servers display Highlight all entries and click Select Server Select OrderEntryServer and continue with the wizard N DO oO FP WD When the WebSphere Application Server wizard asks if you want to re generate the deployment code select No Appendix A Downloading and installing the OrderEntry application 227 Importing the BRBeans rules Important If you plan to go through the BRBeans development process skip the rest of this appendix The steps necessary to develop deploy and test the OrderEntry application with BRBeans are described in Chapter 3 The Business Rule Beans service on page 15 The application is almost ready to be tested Only t
103. JB NewInstance oXJB FindClass java util Properties Create an XJB helper object that will facilitate calling methods of objects that take parameters that are inherited Dim oArgs As Object Set oArgs oXJB GetArgsContainer Build our properties using the normal naming string constants Dim Context_PROVIDER_URL As String Dim Context_INITIAL_CONTEXT_FACTORY As String Context_PROVIDER_URL oXJB FindClass javax naming Context PROVIDER_URL Context_INITIAL_CONTEXT FACTORY oXJB FindClass javax naming Context INITIAL_CONTEXT_FACTORY PROVIDER_URL is the location of the Bootstrap Host XJBPutProperty oXJB p Context_PROVIDER_URL iiop 127 0 0 1 XJBPutProperty oXJB p Context_INITIAL_CONTEXT_FACTORY com ibm websphere naming WsnInitialContextFactory Create the initial context Dim oInitialContext As Object oArgs Clear oArgs AddObject java util Hashtable p Set oInitialContext oXJB NewInstance oXJB FindClass javax naming InitialContext oArgs Dim oJava0bj As Object CustomerGlobal is the JNDI reference name for the Customer EJB Set oJava0bj oInitialContext ookup CustomerGlobal Dim oArgsb As Object Set oArgsb oXJB GetArgsContainer Narrow it This is more EJB J2EE code Here we use or JMethodArgs object i to coerce our EJB object to a specific class In this case our EJB Home class Notice that we are calling the static narrow method on a Class Proxy object that was
104. JMSException je System out printIn JMS failed with je Exception le je getLinkedException if le null System out printIn linked exception le catch Exception exc finally System out print n Unexpected error exc Ensure JMS objects are closed try if oTopicSession null System out printIn Closing session oTopicSession close if oTopicConnection null System out printIn Closing connection oTopicConnection close catch JMSException je je printStackTrace System out print n Unexpected error failed with je 4 4 Advanced JMS facilities This section discusses advanced JMS facilities that need to be configured for high performance secure and robust messaging infrastructure 4 4 1 Transaction support The transactional behavior of the message read from the JMS destination can be configured for each listener stanza in the XML configuration file If transactional handling is specified before the message is read from the destination a global transaction is started by JMS Listener The transaction is committed or rolled back when the onMessage method has completed 84 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The removal of the message from the destination is directly associated with the completion of the transaction If the transaction is marked for rollback only the rollback of th
105. M WebSphere InfoCenter Place the 0E_HOME ActiveX OrderEntry ear file in the WAS_HOME WSsamples Client J2EE directory Here WAS_HOME is where you installed the WebSphere Application Client for example C IBM WebSphere AppClient The EAR file is a slimmed down version of the full O0E_HOME OrderEntry ear file It only contains components necessary for J2EE client access Use the following command to launch the ActiveX client application WAS_HOME Enterprise bin launchClientXJB OE_HOME Activex OrderEntryClient exe Put the path in if it contains spaces Fill out the bootstrap server and port fields in the options panel Appendix A Downloading and installing the OrderEntry application 229 230 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Additional material This redbook refers to additional material that can be downloaded from the Internet as described below Locating the Web material The Web material associated with this redbook is available in softcopy on the Internet from the IBM Redbooks Web server Point your Web browser to ftp www redbooks ibm com redbooks SG246504 Alternatively you can go to the IBM Redbooks Web site at ibm com redbooks Select the Additional materials and open the directory that corresponds with the redbook form number SG246504 Using the Web material The additional Web material that accompanies this redbook includes the following f
106. MQSeries EI Qin 0 Local Queue Managers El Qout 0 Local E QM_p23bk52h ol Efe p23bk66h S oe Advanced Clusters Putting Message To Queue Manager 23666 Queue Qin Message Data 0001 000001 50 The queue which will receive the test message is on this computer The message will be put directly on the queue Figure 4 20 Injecting test messages into the Qin JMS destination queue 8 When the message bean StockDeliveryUpdate is invoked it places a confirmation message on the output queue Qout Right click the Qout queue and select Browse Messages 9 Select the last displayed message within the list and click Properties This displays the properties for the message 10 Select the Data tab to view the content for the message and verify that the stock level was increased for the item see Figure 4 21 Chapter 4 Extended Messaging Service 75 m MQSeriesP2p Console Root IBM MQSeries Queue Managers p23bk66h Queues fi Console Window Help Action view Favorites ll gt Slm x 2 lalam EEY Tree Favorites Name Current Depth Cluster Namelist__ Hosting Queue Manager E Console Root El DEFAULT o Local YO IBM MQSeries El Qin a Local 5 Queue Managers El Qout 1 Local H E QM_p23bk52h on xj DRO p23bk66h 4 Queues Queue Manager Name p23bk66h Advanced Clusters Queue Name Qout Position Put Dat
107. O LIBPATH 0E_HOME corba client vb2ejb LIBPATH 0E_HOME corba tools LIBPATH VBROKERDIR 1ib OUT Customer lib def Customer_merged_c obj Vtlib_c obj Vtlib_I_vb obj Creating library Customer 1ib and object Customer exp Linking the Customer dl library link DEBUG NOLOGO INCREMENTAL NO LIBPATH 0E_HOME corba client vb2ejb LIBPATH 0E_HOME corba tools LIBPATH VBROKERDIR lib DLL Customer exp Customer_merged_c obj Vtlib_c obj Vtlib_I_vb obj OUT Customer d11 Building the tools library The tools library is created from the same source files as in Building the tools library on page 167 But some parts of the implementation differ This time we used different compiler flags libraries and include files The creation of the tools library is done with a separate makefile called makefile tools It is called this time from makefile vb2ejb The makefile tools file executes the following steps 1 Compile the tools classes The following output is produced set INCLUDES 1 0E_HOME corba client vb2ejb 1 0E_HOME corba tools I MSVCDir include I VBROKERDIR include I VBROKERDIR include stubs set CC_FLAGS DWIN32 D_USE_NAMESPACE nologo MD GX c DORB_VisiBroker set LIBS LIBPATH 0E_HOME corba client vb2ejb LIBPATH 0E_HOME corba tools LIBPATH C Inprise vbroker 1lib set LD_FLAGS DEBUG NOLOGO INCREMENTAL NO LIBPATH 0E_HOME corba client vb2ejb LIBPATH 0E_HOME corba tools LIBPATH VBROKERDIR 1ib set LIB
108. Orbix naming IOR private String rootIOR null rootIOR readIOR filename Root Naming Context private String readIOR String fileName String what throws FileNotFoundException IOException System out printIn reading what IOR file fileName BufferedReader in new BufferedReader new FileReader fileName String ior in readLine return ior Getting root context by resolving the stringified IOR Example 8 20 shows how the root context of the Orbix naming service is resolved by invoking the string_to_object method in the ORB object Example 8 20 Getting the Orbix root naming context public NamingContext getRootContext NamingContext rootContext null org omg CORBA Object nameServiceObject null System out printIn Getting name server System out printIn By resolving the stringified IOR nameServiceObject this orb string_to_object this rootIOR if nameServiceObject null rootContext NamingContextHelper narrow nameServiceObject check success if rootContext null throw new java lang RuntimeException Unable to locate naming context return rootContext NamingContext rootContext orb getRootContext Binding to the Creditinstitute object Binding to the CreditInstitute object is done as well in the constructor of the wrapper class as shown in Example 8 21 Chapter 8 The CORBA services 205 Example 8 21 Binding the Creditinstitute object System
109. Package Class Home interface StockDeliveryUpdateHome Package Class Remote interface StockDeliveryUpdate Package Class Class Add Edit 2 H A J2EE View Navigator BZ Outline i An outline is not available Key class Add persistence fields to the bean Package Remove F Use the single key attribute type for the key class 7 22 fe ee ee Figure 4 18 Creating the StockDeliveryUpdate bean for the OrderEntry application 4 Add the onMessage method shown in Example 4 3 This is a required method Example 4 3 The onMessage method public void onMessage javax jms Message inputMessage System out printIn StockDeliveryUpdateBean onMessage try StringTokenizer st new StringTokenizer TextMessage inputMessage getText System out printIn StockDeliveryUpdateBean onMessage TextMessage inputMessage getText TextMessage inputMessage getText int count 0 String tempValues new String st countTokens while st hasMoreTokens tempValues count st nextToken System out print n StockDeliveryUpdateBean onMessage increasing stock count at warehouse tempValues 0 for item tempValues 1 n by n tempValues 2 items int iStockLevel Chapter 4 Extended Messaging Service 69 updateStockValue tempValues 0 tempValues 1 Integer
110. Point Disable caching for demonstration purpose tp disableCaching Set the combining strategy to return the first The second parameter specifies that this combining strategy will be applied to all rules classifier and base tp setCombiningStrategy CombiningStrategy RETURN FIRST tp ALL_RULES Pass the purchase total and amount of YTD purchases to the rule Object firingParams new Integer purchaseAmount new Integer amountYTD Object result tp trigger null firingParams DiscountRules CalculateDiscount if result null jtemsViewBean setApplicationError The rule returned null Jelse Rule successfully called customerDiscount Integer result intValue itemsViewBean setCustomerDiscount customerDiscount Testing the application To see the results of the getCustomerFirst method implementation test the application 1 In the WebSphere Administrative Console start OrderEntryServer if it is not already started 2 Bring up application home page http localhost lt port_number gt OrderEntry index htm 3 Select New Order and type in customer ID which is 0001 4 Click the Submit button You can see the discount value based on the customer level This customer has qualified for the Platinum level and receives a 10 discount Order Total 0 Discount 10 Total Order Discount 0 5 Select New Order and type in the customer ID which is 0005 6 Click t
111. RBA WStringValue_ptr wsv return com ibm ws VtlUtil WStringValueToString wsv Building the CustomerKey valuetype The findByPrimaryKey method of CustomerHome takes as a parameter an object of the type CustomerKey Since this is self defined it cannot be part of the IBM valuetype library So to use this method we have to create our own C valuetype of that class This means that we have to re implement in C the CustomerKey class with its methods that are described in the interface Cus tomerKey hh Our example already includes the final version of the implementation files We describe the steps that we have gone through These are the steps to create the CustomerKey valuetype 1 Generate the skeleton files from the IDL by running these two commands cd 0E_HOME corba client ibm2ejb idic J Djava ext dirs WAS HOME 1lib WAS HOME Enterprise lib I d com ibm itso roch wasaejb mcpponly md1Iname Customer eih ic com ibm itso roch wasaejb CustomerKey id 2 Edit the files produced in the previous step CustomerKey ih CustomerKey_I cpp 3 Add the following inheritance to the CustomerKey ih file to use the default implementation class The following line class com_ibm_itso_roch_wasaejb CustomerKey_Imp virtual public com ibm itso roch wasaejb CustomerKey virtual public CORBA DefaultValueRefCountBase was changed to class com_ibm_itso_roch_wasaejb_CustomerKey_Imp 1 virtual public
112. Sed ALY Ee 67 4 2 7 Testing the JMS sample code a a nuuanu cette 74 Copyright IBM Corp 2002 iii iv 4 3 JMS publish subscribe 0 0 0 et eee 76 4 3 1 The core components of JMS publish subscribe 0 20 eee 77 4 3 2 MQSeries message broker 1 1 2 0 cee ee eee 77 4 3 3 The JMSAdmin tool 00 78 4 3 4 WebSphere Application Server 00 eee 80 4 3 5 JMS Listener XML configuration file 0 2 0 2 0 cece eee 81 4 3 6 The message bean for the publish subscribe model 82 4 4 Advanced JMS facilities 20 0 te eee 84 4 4 1 Transaction support aoe a e aiie a a aeiia eee 84 4 4 2 JMS Listener threads and MaxSessions 000 0c eee eee eee 86 4 4 3 Exception Nand ling o srne earar En kee ed Ae alah ie aE ale aso ow Maree aee 86 AAA Decu errenda Mite aa hace aia det A she erin chive Maa teh ah reed Ad Mite ait 88 4 4 5 MQSeries clustering auaa cece teens 88 4 5 The future of WebSphere messaging aaan aaan 89 Chapter 5 The WorkArea service 0 0 00 cece eae 91 5 1 WorkArea overvieW 0 0 ce ee eee tees 92 5 1 1 WorKArea SOD ri banaue asia a e risa eae a eae ase A a tieacs 92 5 2 Using WorkArea in the example application a n auaa aaan 93 5 2 1 Binding to the WorkArea facility 0 cee eee 93 5 2 2 Creating and populating WorkArea 000 ee 94 5 2 3 Accessing WorkAreas si fede dalek eee so
113. Series Queues Figure 4 6 The JMS Provider and admin within the JMS architecture The JMSAdmin tool is supplied with MQSeries It can be found in the lt MQSeries install home gt java bin directory Edit the JMSAdmin bat file as follows to ensure that it uses the version of Java provided by WebSphere and includes additional directories in its run time 1 Add the following path onto the Java call within the JMSAdmin bat file WAS_HOME java jre bin 56 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 2 Provide the following directive to the Java run time as an option Djava ext dirs WAS HOME java lib WAS_HOME java jre lib ext WAS_HOME 1ib WAS_HOME java 1ib MQSeri esHome Java 1ib Here WAS_HOME is the environment variable that points to the installation directory for WebSphere Application Server MQSeriesHome is an environment variable pointing to the installation home directory of MQSeries Refer to the sample JMSAdmin bat file in Example 4 1 Example 4 1 JMSAdmin script used for the OrderEntry sample cls echo off rem IBM MQSeries JMSAdmin Tool Execution Script rem for Windows NT rem rem Note that the properties passed to the java rem program are defaults and should be edited rem to suit your installation if necessary set WAS HOME C IBM WebSphere AppServer set MQSeriesHome C IBM MQSeries set libPaths set 1ibPaths 1ibPaths WAS HOME java lib set 1ibPat
114. SeriesWavallibicom ibm mg jar CABMIMaSeriesWJavallibicom ibm maims jar Classname lcom ibm cmm listener JMSListenerStub Configuration file URL c UsersiCaviPtoPiimsconfig xml V Enabled OK Cancel Help Figure 4 16 Configuring the JMS Listener service for the point to point model 4 2 5 JMS Listener XML configuration file The operation of the Extended Messaging Service is controlled by an XML configuration file which you edit to specify properties of the service Consider for example the identities of JMS destinations that are to be monitored the transactional requirements and the name of the message bean to process messages When an application server is started it initializes the JMS Listener manager based on the JMS Listener XML configuration file For each message bean that takes part in JMS there is a corresponding listener entry in the JMS XML configuration file Chapter 4 Extended Messaging Service 65 Each JMS Listener configuration is defined within the lt Listener gt XML tag of the XML configuration file It is sometimes referred to as the listener stanza Figure 4 17 shows the relationship between JNDI entries in WebSphere Application Server and XML tags in the listener stanza of the configuration file homeJNDIName for the message bean is registered with JNDI when the message bean is installed in WebSphere Application Server WebSphere Application Server Send JMS JNDI Entries
115. Start gt Programs gt IBM WebSphere gt Application Server V4 0 AE gt Start Admin Server Start the WebSphere Administrative Console by clicking Start gt Programs gt IBM WebSphere gt Application Server V4 0 AE gt Administrator s Console Create a new JDBC provider entry JDBC driver with the following parameters Name OrderEntryJDBC Implementation class COM ibm db2 jdbc DB2XADataSource 224 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Driver file lt DB2_INSTALL_DIR gt SQLLIB java db2java zip where lt DB2_INSTALL_DIR gt is the DB2 installation directory Note Make sure you updated DB2 to use Java 2 Create a new datasource with the following parameters JDBC provider OrderEntryJDBC Name OrderEntryDS JNDI name jdbc MyApp Database name ORDERENT User A user ID with sufficient authority to access the database Password A password for a user ID specified in the previous step Create another datasource with the following parameters JDBC provider OrderEntryJDBC or Sample DB Driver this JDBC provider is created when you install WebSphere Application Server Advanced Edition Name BRBDS JNDI name jdbc BRBDS Database name BUSRULES User A user ID with sufficient authority to access the BUSRULES database Password A password for a user ID specified in the previous step You need also create a separate a
116. StockHome javax rmi PortableRemoteObject narrow tempObject StockHome class Get the entity bean with a specific primary key com ibm itso roch wasaejb Stock stockEJB null StockKey stockKey new StockKey warehouseld itemld try System out printIn StockDeliveryUpdateBean finding stock bean stockEJB com ibm itso roch wasaejb Stock stockHome findByPrimaryKey stockKey System out printI n StockDeliveryUpdateBean finding stock bean end catch FinderException oException System out printIn StockDeliveryUpdateBean exception oException printStackTrace System out print n StockDeliveryUpdateBean exception end System out print n StockDeliveryUpdateBean found bean now updating values stockEJB increaseStockQuantity newStockDel ivered int iStockQuantity stockEJB getStockQuantity System out print n StockDeliveryUpdateBean stock value is now iStockQuantity System out print n StockDeliveryUpdateBean found bean now updating values end return iStockQuantity 7 Create a method called putMessage to place messages on an output queue Qout shown in Example 4 6 Qout was created using the MQSeries Explorer refer to Figure 4 5 on page 55 The putMessage method takes the target queue as a JNDI path a message ID to enable message correlation and the message data as a String In Example 4 6 the key objects for posting messages to
117. The next step is to get the root context of the naming service Example 8 7 shows the method that handles this task First the initial reference of the NameService is resolved by using string_to_object and then narrowed to a NamingContext object Example 8 7 Get root context by resolving the stringified IOR CosNaming NamingContext_ptr MyOrb getRootContext CosNaming NamingContext_ptr rootContext NULL try t println Getting name server CORBA Object_var obj else t printIn By resolving the stringified IOR obj _orb gt string_to_object _rootIOR c_str if CORBA is_nil obj err printin resolve_initial_references NameService returned nil nMake sure your server is running and you set SOMCBPROPS rootContext CosNaming NamingContext _narrow obj if CORBA is_nil rootContext 184 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide err printIn name server narrowed to nil return rootContext Again this step differs from the step for the IBM client shown in Example 8 2 on page 171 Binding CustomerHome The connection to the CustomerHome is established by the CustomerFactory This step is exactly the same as described for the IBM client in Example 8 3 on page 172 Creating a customer After a CustomerHome is instantiated all methods of the CustomerHome can be used This section cover the creation of a customer The other calls
118. This opens the web xml file in the Editor view Chapter 3 The Business Rule Beans service 19 v Click the References tab vi Add three EBJ references as shown in Table 3 1 vii Save the changes Table 3 1 EJB references for BRBeans ejb com ibm ws brb Rule com ibm ws brb RuleHome com ibm ws brb Rule ejb com ibm ws brb RuleFolder com ibm ws brb RuleFolderHome com ibm ws brb RuleFolder ejb com ibm ws brb RuleHelper com ibm ws brb RuleHelperHome com ibm ws brb RuleHelper i Change the JNDI names of BRBeans rules EJBs to be specific for your application i In WebSphere Studio Application Developer open the J2EE Perspective select Perspective gt Open gt J2EE ii Select the J2EE View tab iii Expand the EJB Modules folder iv Right click BRBeansDB2 and select Open With gt EJB Extension Editor v Select the Bindings tab vi On the Bindings tab expand BRBeansDB2 vil Expand each EJB and change JNDI names for each bean and the beans it references respectively to brbeans OrderEntry Rule brbeans OrderEntry RuleFolder brbeans OrderEntry Rul eHel per Note Make sure to expand each EJB and change JNDI names for each EJB reference vili Save the changes ix In the Navigator view select the folder under OrderEntryWeb gt webApplication gt WEB INF x Double click the ibm web bnd xmi file xi Select the Source tab xii Change the JNDI names of BRBeans EJBs as shown in Example 3 1 xiii Save the
119. V losyiteicem software WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The ultimate reference to WebSphere Enterprise Services Programming examples of Enterprise Services usage Tips and techniques from the developers Aleksandr Nartovich Keith Bennett Henning Burgmann Cavin Edwards Elena Lowery Ruth Poole ibm com redbooks Red h 00 ks International Technical Support Organization WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide February 2002 SG24 6504 00 Take Note Before using this information and the product it supports be sure to read the general information in Special notices on page vii First Edition February 2002 This edition applies to Version 4 0 of IBM WebSphere Application Server Enterprise Edition for use with the Windows NT and Windows 2000 operating systems Comments may be addressed to IBM Corporation International Technical Support Organization Dept JLU Building 107 2 3605 Highway 52N Rochester Minnesota 55901 7829 When you send information to IBM you grant IBM a non exclusive right to use or distribute the information in any way it believes appropriate without incurring any obligation to you Copyright International Business Machines Corporation 2002 All rights reserved Note to U S Government Users Documentation related to restricted rights Use duplication or disclosure is subject to restrictions set fort
120. YTD Integer parms 1 intValue Level and discount variables were initialized in init if amountYTD gt platinumLevel discount platinumDiscount else if amountYTD gt goldLevel discount goldDiscount else if amountYTD gt preferredLevel discount preferredDiscount return new Integer discount DiscountByTotal returns a discount percentage based on the amount of purchase Rule implementor initialization parameters include three levels of purchase amount required to qualify for a certain discount and discount values for each level Business logic is implemented in the fire method as shown in Example 3 6 Example 3 6 Implementation of the DiscountBy Total fire method public Object fire TriggerPoint tp Object target IRuleCopy rule java lang Object parms throws BusinessRuleBeansException int discount 0 int amount 0 if initialized Chapter 3 The Business Rule Beans service 33 The first parameter is the amount of purchase amount Integer parms 0 intValue The customer s amount of purchase is compared against 3 different values to figure out a discount The 3 levels of the discounts with corresponding eligible purchase amounts are defined through the Rule Management application if amount gt total3 discount level3Discount else if amount gt total2 discount level2Discount else if amount gt totall discount
121. _EX DORB WebSphere ibm2ejb cpp ibm2ejb cpp Compiling the ProgVals class cl 1 0E_HOME corba client ibm2ejb 1 0E_HOME corba tools 1 WAS_HOME Enterprise include I include GX c nologo MD Od DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE DUSE_JAVA_EX DORB WebSphere ProgVals cpp ProgVals cpp 2 Link the executable which produces the output x Linking the ibm2ejb exe executable link NOLOGO INCREMENTAL NO DEBUG LIBPATH 0E_HOME corba client ibm2ejb LIBPATH 0E_HOME corba tools LIBPATH WAS_HOME Enterprise lib LIBPATH MSVCDir lib somororm 1ib somosalm Jib Vtlib 1ib kernel32 1ib user32 1ib ibm2ejb obj ProgVals obj Customer 1ib F Henning oe corba tools tools lib SUBSYSTEM CONSOLE OUT ibm2ejb exe Creating library ibm2ejb lib and object ibm2ejb exp The output of the whole process is the executable file ibm2ejb exe Running the client To run the client you should execute the following command The general usage of the executable is ibm2ejb method lt method gt id lt id gt forename lt fname gt lastname lt name gt phone lt phone gt The following methods are available create id lt id gt forename lt fname gt lastname lt Iname gt phone lt phone gt remove id lt id gt getPhone id lt id gt setPhone phone lt phone gt findByPrimaryKey id lt id gt YYYY Y To create a customer with default values you call ibm2ejb method create id 1234 forename joe lastname m
122. _FLAGS NOLOGO cd 0E_HOME corba tools nmake nologo f makefile tools Compiling the Trace class cl 1 0E_HOME corba client vb2ejb 1 0E_HOME corba tools I MSVCDir include 1 VBROKERDIR include 1 VBROKERDIR include stubs DWIN32 D_USE_NAMESPACE nologo MD GX c DORB_VisiBroker DSOM DLL_tools Trace cpp Trace cpp Compiling the Error class cl 1 0E_HOME corba client vb2ejb 1 0E_HOME corba tools IC MSVCDir include 1 VBROKERDIR include 1 VBROKERDIR include stubs DWIN32 D_USE_NAMESPACE nologo MD GX c DORB_VisiBroker DSOM_DLL_tools Error cpp 180 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Error cpp Compiling the Warning class cl 1 0E_HOME corba client vb2ejb 1 0E_HOME corba tools I MSVCDir include 1 VBROKERDIR include 1 VBROKERDIR include stubs DWIN32 D_USE_NAMESPACE nologo MD GX c DORB_VisiBroker DSOM_DLL_tools Warning cpp Warning cpp Compiling the MyOrb class cl 1 0E_HOME corba client vb2ejb 1 0E_HOME corba tools I MSVCDir include 1 VBROKERDIR include I1 VBROKERDIR include stubs DWIN32 D_USE_NAMESPACE nologo MD GX c DORB_ VisiBroker DSOM DLL_tools MyOrb cpp MyOrb cpp Compiling the CustomerWrapper class cl 1 0E_HOME corba client vb2ejb 1 0E_HOME corba tools I MSVCDir include 1 VBROKERDIR include 1 VBROKERDIR include stubs DWIN32 D_USE NAMESPACE nologo MD GX c DORB_VisiBroker CustomerWra
123. _HOME corba server ejb2orbix nmake f makefile ejb2orbix cleansrv Generating the server sources The makefile calls first the Orbix Code Generation Toolset in order to create the sources and the makefile for the C server It not only creates the server main but also delivers an implementation for the interface which sends back random answers makefile ejb2orbix generates the server sources which produces the following output 192 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide idlgen cpp_poa_genie tcl ns all dir srv CreditInstitute id CreditInstitute idl cpp_poa_genie tcl creating srv it_servant_base_overrides h cpp_poa_genie tcl creating srv it_servant_base_overrides cxx cpp_poa_genie tcl creating srv com_ibm_itso_roch_credit_CreditInstituteImp h cpp_poa_genie tcl creating srv com_ibm_itso_roch_credit_CreditInstituteImp cxx cpp_poa_genie tcl creating srv server cxx cpp_poa_genie tcl creating srv client cxx cpp_poa_genie tcl creating srv call_funcs h cpp_poa_genie tcl creating srv call_funcs cxx cpp_poa_genie tcl creating srv it_print_funcs h cpp_poa_genie tcl creating srv it_print_funcs cxx cpp_poa_genie tcl creating srv it_random_funcs h cpp_poa_genie tcl creating srv it_random_funcs cxx cpp_poa_genie tcl creating srv Makefile Note As you can see the genie creates a client as well However there have been compilation problems with that client For that reason we create additionally
124. aging Support Service Resour Descnon 4 JDB escription Extended Messaging Support enables automatic asynchronous deliver of messages to an 5 a enterprise application Jav Classpath CABMMOASeriesiJava libicom ibm mg jar CABMMOASeries Javallibicom ibm mgjms jar HO URL m z2 Classname ftom ibm cmm listener JMSListenerStub JMS Configuration file URL C Users CaviPubSub jmsconfig xml oF M Enabled ype Time E 10 22 01 5 7 E EE OK Cancel Help Figure 4 26 Configuring the JMS Listener service for the publish subscribe model 4 3 5 JMS Listener XML configuration file The XML configuration file determines which message beans are invoked for a message arriving on a given topic A typical configuration file is shown in Example 4 8 where gt JMSDestination specifies the topic or topics if using a wildcard to which the JMS Listener responds gt JMSDestinationType specifies the type of JMS Destination that this listener stanza is for In our example it is topic gt JMS ConnectionFactory specifies the connection factory via its JNDI name used for this JMS Listener Example 4 8 A typical JMS Listener XML configuration file for the publish subscribe model lt Config gt lt Pooling gt lt Timeout gt 100636 lt Timeout gt lt Threshold gt 36 lt Threshold gt lt Pool ing gt lt Listener gt lt HomeJNDIName gt OrderEntry JMS StockDel i veryUpdat e lt HomeJNDIName gt
125. ailable It can also detect when a queue is full and no longer accepts messages If all physical queues are full on the system the control point continues to accept messages The messages are stored on an internal queue until the physical queues can accept messages In an advanced configuration the MQSeries cluster control point can contain a modified exit routine that can be called to control the distribution of messages to the physical queues Another configuration value that can be used in the control of messages is to intentionally set the physical size of the queue depth to a relatively small number The cluster control point would control messages to the queues if there was a problem with MQSeries WebSphere Application Server or a system failure the control point would manage the returning of messages to the available systems This technique would allow for an earlier detection of a WebSphere Application Server failure It would prevent a large number of messages from being orphaned on a machine when a failure occurs It would also allow for messages that occurred close to the failure to be handled by an alternate system Publish subscribe model clustering restriction The use of MQSeries publish subscribe in an MQSeries cluster with cluster queues is not a practical configuration This is because a subscriber has an identity which in MQSeries is identified by the combination subscriber queue name Queue manager name Correlation ID S
126. ain areas gt Enterprise class functionality gt Enterprise class quality of service QoS WebSphere Enterprise Services in WebSphere Application Server Enterprise Edition Version 4 0 fall primarily into the category of enterprise class functionality Chapter 1 WebSphere Application Server Enterprise Edition overview 3 The second category of enterprise class QoS is understood as enterprise level scalability and performance Even though WebSphere Application Server Advanced Edition provides several QoS functions the sophisticated Workload Management WLM algorithm support for server clustering improvements in the performance of Container Managed Persistence CMP entity beans and the use of HTTP communication protocol between Web server and WebSphere Application Server WebSphere Application Server Enterprise Edition targets more advanced functions and services for enterprise class QoS All WebSphere Enterprise Services can be divided into three groups of functionality gt Integration and adaptability This group includes JMS Listener CORBA interoperability CORBA C SDK ActiveX bridge BRBeans and WorkArea services gt Business process management This group is presented by the BPBeans service gt Globalization Internationalization service falls into this category The main support in WebSphere Application Server Enterprise Edition is added in the area of integration and adaptability That s because the integration
127. ameter for the Platinum level and click Change Change the value to 20000 Note In the production environment we recommend that you use Quick Copy see Using Quick Copy in the Rule Management Application on page 23 to change the rule initialization parameters Test the rule see step 7 Use the same ID as in the first test 0007 The customer level has changed Customer ID 0007 Name Jim J Fair Customer Level Gold You have successfully implemented a simple classifier rule We will use the same three step process to implement more complex rules described later in this chapter gt Creating a rule implementor gt Configuring a BRBeans rule in the Rule Management Application gt Placing a trigger point in the rule client 3 2 4 Implementing base rules 32 As we examine the implementations of base business rules we review the use of strategies in the BRBeans framework This section discusses the implementation of this business rule Base rule Customers can get discounts based on a customer level the total amount of purchase and other factors holiday discounts promotions on certain items and so on Discount values and specials may change frequently The rule definition states that a customer discount is a cumulative value derived from several factors We need to implement the rule in a way that allows us to add new discount factors and change discount values To achieve this flexibility we implement each dis
128. anager PortableServer POA_var my_poa create_simple_poa my_poa root_poa root_poa_manager First you get access to the root POA object by bootstrapping Next you obtain a reference to the root POA manager object which manages a set of POAs Then you instantiate your own POA which defines several policies These policies determine the thread handling how objects are activated and so on We define a single threaded POA for transient objects 196 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Creating and activating servant objects Next the implementation object is instantiated and activated Activation means that the object is registered with the POA POA returns a unique identifier Example 8 12 shows how this is done in the generated code Example 8 12 Create and activate servant object PortableServer Servant the_com_ibm_itso_roch_credit_CreditInstitute 0 PortableServer ObjectId_var oid the_com_ibm_itso_roch_credit_CreditInstitute com_ibm_itso_roch_credit_CreditInstituteImp _create my_poa oid my_poa gt activate_object the_com_ibm_itso_roch_credit_CreditInstitute Connecting to nameservice The next steps are shown in Example 8 13 The server connects to the Orbix nameservice by bootstrapping and writes the IOR of the root context into a file Example 8 13 Connecting to nameservice and writing IOR void writeIOR CORBA 0bject_ptr obj const char fileName char iorfile
129. ansactional connection factory Defined as WSTCP in the JMSAdmin tool that supports transactional messaging where messages can be placed back on the topic in the event of message bean processing failure 4 3 4 WebSphere Application Server 80 The components found on WebSphere Application Server are gt JMS Provider This requires configuration identical to that for point to point gt JNDI entries Publish subscribe uses topic connection factories and topics in place of queues as JMS destinations Messages are published to the JMS destination As in the case of point to point messaging all JMS resources have a corresponding JNDI entry in the WebSphere Application Server WebSphere Application Server is used for all JNDI lookup gt JMS Listener For the publish subscribe messaging model the configuration for the JMS Listener within WebSphere Application Server must have an XML configuration file containing publish subscribe entries as shown in Figure 4 26 The JMS Listener support is enabled in the same way as for the point to point model see JMS Listener on page 63 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide wri wie a mbantu yew muUuiES Nodes H P238K66H ea Ber Servers 7 i General Advanced File i E Generic Servers n Sc Ca RT Fa Ener 5 Edit Custom ServiceExtended Messaging iol xj H E P23 SEI Ordi General custom oO 01 Name Extended Mess
130. application components can use both Internationalization and InvocationInternationalization interfaces However in the current release according to the SSI policy the caller context is used as the invocation context for the server application components For more information on the SSI policy see Server side Internationalization SSI policy on page 111 6 2 3 The Internationalization Service API Applications use the service to access and manage internationalization context Three interfaces are provided by the com ibm websphere il8n context package for this purpose gt com ibm websphere il8n context UserInternationalization gt com ibm websphere il8n context Internationalization gt com ibm websphere il8n context InvocationInternationalization The Userlnternationalization interface The UserInternationalization interface provides a factory for obtaining the internationalization API objects These objects give access to the desired type of an internationalization context caller or invocation contexts The interface is shown in Example 6 1 108 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Example 6 1 The Internationalization service interface public interface UserInternationalization public Internationalization getCallerInternationalization public InvocationInternationalization getInvocationInternationalization The UserInternationalization interface defines two methods gt In
131. are similar The actual creation of the Customer is exactly the same like described for the IBM client in Example 8 4 on page 173 The only difference is the implementation of the helper method to convert between WStringValue and char For VisiBroker we cannot use the method from the IBM Vt1Util class We implement a simple version of that method Example 8 8 shows this helper method Example 8 8 Conversion to WStringValue CORBA WStringValue_ptr MyOrb stringToWStringValue char str try int n strlen str 1 CORBA WChar buffer new CORBA WChar n mbstowcs buffer str n return new CORBA WStringValue buffer catch return NULL 8 3 4 Problem determination One major problem is how the clients find their servers Therefore it is good to check the entries in the namespace Furthermore it is a great help to get additional CORBA communication traces output Checking the namespace Two major mistakes concerning the namespace are gt The server entry is not there at all because the server may not have been started gt The server entry has a different name than the client expects It is easy to find these mistakes if you simply print the complete namespace and check it for the entry your client is expecting WebSphere Application Server is shipped with a tool called dumpnamespace bat that gives you this functionality You call setupcmd ine dumpnamespace If it is not working you should
132. array is null the method returns an array of locales of length one containing the default locale of the process associated with the execution of this method The method is useful if the first locale in the array is not recognized or not supported by the server A different locale from the array could be selected gt java util Locale getLocale Returns the first element from the array of locales associated with the current thread If the array of locales is null the method returns the default locale of the process associated with the execution of this method gt java util TimeZone getTimeZone Returns the SimpleTimeZone object associated with the current thread If the time zone is null the method returns the default time zone of the process associated with the execution of this method Chapter 6 The Internationalization service 109 Note Due to the inheritance caller and invocation contexts can be accessed using the Internationalization interface The InvocationInternationalization interface The InvocationInternationalization interface allows read and write access to the invocation context Use this interface to read or modify the invocation context But remember client and server application component access to the invocation context is governed by the CSI or SSI policy respectively Example 6 3 shows the InvocationInternationalization interface Example 6 3 The InvocationInternationalization interface public interface I
133. as an activity in the BPBeans framework The com ibm bpbeans Activity interface declares just a few methods that an activity has to implement It doesn t impose any restrictions on the business methods A Java developer determines the business methods a given activity should have 212 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Note Actually a JavaBeans class that does not implement the com ibm bpbeans Activity interface can be used as an activity but the JavaBean cannot send messages to other activities It can only receive messages and optionally send a single reply to the message An activity is invoked by receiving a message on its input port Note There are four types of ports in the BPBeans framework Input port InOut port Outln port Output port YYY Yy Receiving a message results in the execution of a method The method that should be invoked and the input parameter type are declared as the properties for this input port For example the ReceiveActivity activity part of the BPBeans tutorials has input and output ports The input port has three properties that define how another BPBeans component can send a message aka invoke to this input port gt The property Java class name defines the name of the Java class interface that implements or declares the functionality of this port In our example the com ibm bpbeans InputPort interface is declared The InputPort interface has tw
134. at type The bridge uses the Reflection API to examine or introspect the return value to determine its actual data type If the actual data type corresponds to a COM primitive see Table 7 1 and Table 7 2 the bridge will convert the object to the associated COM primitive and pass the primitive to the client application The return value should then be assigned to a variable of the appropriate type If the return type does not correspond to a COM primitive either a JObjectProxy or JClassProxy object is returned to the ActiveX process Both JObjectProxy or JClassProxy objects can be assigned to a variable declared as type Object in the Visual Basic code Example 7 12 demonstrates handling both primitive and Object return types 1 The penultimate line of code calls the get7ime method on a JObjectProxy object representing a java util Calendar instance The getTime method of the java util Calendar instance returns a java util Date object although the bridge returns a JObjectProxy object representing the Date object The code then assigns that JObjectProxy object to oDate that was declared as type Object 2 The getTime method of oDate is then called and the bridge invokes the getTime method of the java util Date object which returns a Java primitive int The bridge converts this int to the corresponding COM primitive Long The code then assigns this value to the variable time which was declared as type Long Example 7 12 Handling return va
135. at uses valuetypes sample Building the client To build the client you simply have to run a makefile by executing the following two commands cd 0E_HOME corba client ibm2ejb nmake f makefile ibm2ejb This execute all the steps that are described in the subsections of this section Create the IDL files Compile the IDL files Compile and link the stubs Build the tools library Build the main object and link the executable Ci ND We show the output of the commands that are executed by the makefile You don t have to execute any of the commands manually But you could do so if you are interested in building the client manually step by step The nmake command is described in detail in the online documentation of Microsoft Visual C Chapter 8 The CORBA services 165 nmake may execute the commands in a different order because it doesn t follow a sequence of commands but resolves dependencies To delete all the generated files and directories you call the two commands cd 0E_HOME corba client ibm2ejb nmake f makefile ibm2ejb clean Creating the IDL files The CORBA interfaces are always described in IDL notation They are derived from the class files of the CustomerBean The creation of the IDL files is done with a separate makefile called makefile interface This makefile is called by the main makefile ibm2ejb and executes the following steps 1 Extract the classes from the EAR file which produces the
136. ates and or other countries UNIX is a registered trademark in the United States and other countries licensed exclusively through The Open Group SET SET Secure Electronic Transaction and the SET Logo are trademarks owned by SET Secure Electronic Transaction LLC Other company product and service names may be trademarks or service marks of others viii WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Preface With the advent of Java 2 Platform Enterprise Edition J2EE application servers companies are beginning to adopt the programming model that offers new levels of portability flexibility reuse and scalability Complementing J2EE technology the emerging set of Web services standards arms companies with even greater business flexibility to compete in a changing world The most sophisticated e businesses however need to extend these industry standards to meet important enterprise requirements In response to the needs of the most demanding customers IBM delivers the new WebSphere Enterprise Services that are part of WebSphere Application Server Enterprise Edition Version 4 0 This IBM Redbook discusses the new WebSphere Enterprise Services and shows the best practices for using the services in the applications The target audience for this book is the I T specialist and application developers Some parts of the book such as Business Rule Beans and Business Process Beans will be of particular inter
137. ava lang String Implementation of the fire method is shown in Example 3 3 Example 3 3 Implementation of the fire method public Object fire TriggerPoint tp Object target IRuleCopy rule java lang Object parms throws BusinessRuleBeansException String classification null int amount 0 if initialized One parameter is expected the amount of customer purchases YTD Imp ementorHelper assertParamLength parms 1 CustomerClassification fire amount Integer parms 0 intValue if amount gt platinumLevel classification PLATINUM LEVEL else if amount gt goldLevel classification GOLD LEVEL else if amount gt preferredLevel classification PREFERRED_LEVEL selse classification LEVEL_NA return classification getDescription This method returns the method description 3 Save the CustomerClassification class Chapter 3 The Business Rule Beans service 27 The complete code for the rule implementation is packaged inside the OE_HOME OrderEntry ear file You can also see the source code for CustomerClassification java in Example 3 15 on page 48 Note If you did not implement the CustomerClassification rule class import the class into the OrderEntry project The rule will be used in other examples described later in this chapter Configuring a BRBeans rule 4 Configure the CustomerClassification rule in the Rule Management Application a Make sure that WebSphere Defau
138. bSphere Application Client or when either the JaunchClientXJB or setupCmdLineXJB batch files are run see 7 4 6 Launching a client container in an ActiveX process on page 131 The COM client uses this path to find the EAR file If there is a need to place the file somewhere else the EARFileName parameter in the ActiveX_Config module in the VB Order Entry Client must be changed Run OrderEntryClient exe using the launchC1ientXJB command from a command prompt WAS_HOME Enterprise bin launchClientXJB 0E_HOME Activex OrderEntryClient exe 126 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The first window to appear is the options window Enter information in the Bootstrap Host and Port fields 900 is the default port for WebSphere Application Server The client application will now initialize the JVM and client container and display the main window 7 2 4 The client application components The Visual Basic client code is in OrderEntryClient VB Project The application was originally purely COM based but has been enabled to use the ActiveX to EJB bridge by adding some helper classes and adapting the code The client application can be run within Visual Basic IDE by issuing the command JaunchClientXJB 0E_HOME ActiveX Source OrderEntryClient vbp This launches the Visual Basic IDE in an ActiveX enabled process The client can now be run in debug mode If the launchC1ientXJB batch file is not run the cli
139. blish subscribe model 51 53 clustering restriction 88 core components 77 message bean 82 WebSphere Application Server configuration 80 JNDI context definition 58 JNDI entry 61 80 JNI 122 JObjectProxy 133 K keep alive process 214 key value mode triplet 92 L launchClientXJB 126 listener stanza 66 locale 107 locating a server object 155 loosely coupled connection 211 M Main class 148 maximum send and receive size 103 MaxRetries 86 MaxSessions 86 MDB message driven bean 52 67 89 message bean 52 67 82 developing 68 onMessage 67 message broker 77 message cluster process 214 Message EJB 67 message driven bean MDB 52 67 89 Microsoft Visual C 6 0 163 Model 124 Model View Controller MVC pattern 124 modMain 127 MQSeries 2 MQSeries clustering 88 MQSeries Explorer 55 MQSeries message broker 76 77 N namespace 185 206 Naming Service 155 nested WorkArea 92 97 99 no client container approach 129 non transactional queue connection factory 59 normal mode 97 O Object Adapter 156 Object Request Broker ORB 154 Object type parameter 138 optimized container approach 131 ORB 171 183 196 204 ORB Object Request Broker 154 Orbix 188 190 206 genie 191 Order Line Table Layout ORDLIN 12 Order Table Layout ORDERS 12 OrderEntry application 6 ABC Company 6 application flow 7 configuring WebSphere Application Server 224 customer transaction 7 database layout 10 description of the direct
140. brb folder 4 You should see BRB CacheRule as shown in Figure 3 20 aio x File Edit View Help All Folders a Rule Namespace CustomerRules DiscountRules OrderRules ShippingRules Rules in folder com ibmiwebsphere brb Name a Status E BRB CacheRule in effect a E Tho amp com ibm websphere en A gt 1 Rules Figure 3 20 Modifying the BRB CacheRule 5 Select BRB CacheRule right click and select Properties 6 In the Properties window select the Implementation tab 7 Select the PollFrequency initialization parameter and click the Change button 46 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 8 Change the value of the PollFrequency initialization parameter see Figure 3 21 9 Click OK Change Initialization Parameter q x Description PollFrequency Type String a Value foo 0 00 Cancel Help Figure 3 21 Changing the poll frequency in the Rule Management Application Client side caching is enabled by default Note We disabled client side caching in the examples provided with this chapter to observe the effect of changes made through the Rule Management Application without refreshing the cache Firing location We can eliminate the remote call to fire a BRBeans rule by triggering the rule locally The Firing location parameter is set on the Implementation tab of the rule Properties window in the Rul
141. btains the context associated with the current thread and attaches it to the outgoing request At the server side the Internationalization service detaches the caller s context from the incoming request and associates it with the remote business method thread The service propagates this context on subsequent remote business method invocations to pass the context of the original request down the call chain 6 2 Internationalization context Internationalization context is the information that is propagated and managed by the Internationalization service There are two types of information managed by the service and two types of context Important We use the following terminology throughout the rest of the chapter gt Client refers to an EJB application client deployed inside J2EE client container gt Invoking components may be either an EJB application client or the server application components like servlets or EJBs and server application components are used to identify two parties involved in the internationalization context propagation 6 2 1 The information in the internationalization context The internationalization context consists of an ordered list of java util Locale objects and a java util SimpleTimeZone object java util SimpleTimeZone is a subclass of the abstract class java util TimeZone Locale and SimpleTimeZone are defined in Sun s Java API gt Locale The Locale object is defined by a language and optional count
142. cale is null the service sets the array of locales to an array of length one containing the default locale of the process associated with the execution of this method gt void setTimeZone java util TimeZone This method sets the invocation time zone associated with the current thread to the supplied time zone If the supplied time zone is null or not an instance or subclass of java util SimpleTimeZone the service sets the time zone to the default time zone of the process associated with the execution of this method gt void setTimeZone String This method sets the time zone associated with the current thread to Simp eTimeZone with the supplied ID The general format for time zone ID is either country city or GMT l hh mm For example the time zone ID for the U S Pacific Time zone is America Los_Angeles or GMT 08 00 If the supplied time zone ID is null or unsupported the Internationalization service sets the time zone to a time zone having an 110 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide ID of GMT and the default offset of the process is associated with the execution of this method The use of three letter time zone IDs other than GMT is deprecated A list of supported time zone IDs can be obtained using the java util TimeZone getAvailablelds method See the Java SDK API documentation for more information about time zone IDs 6 2 4 Internationalizatio
143. can be used by server application components to customize results for the client The transfer of the locale and time zone information is done transparently by the Internationalization service The following topics are covered in this chapter When to use the Internationalization service Using the Internationalization service Incorporating the Internationalization service in the example application Configure the Internationalization service on the WebSphere Application Server Enabling the tracing of the Internationalization service on the WebSphere Application Server YYYY Y Note Read the instructions in Appendix A Downloading and installing the OrderEntry application on page 221 to understand the structure and environment settings used for the OrderEntry application Copyright IBM Corp 2002 105 6 1 The Internationalization service overview In a distributed client server environment application processes may run on different machines configured to different locales corresponding to different cultural conventions They may also be located across geographical boundaries With the advent of Internet based business computational models like e commerce more and more clients and servers will operate in different locales and geographical regions The conventional solution for solving locale and time zone mismatch problems is to pass one or more extra parameters on all business methods necessary for conveying either the client s
144. can be changed through an administrative process using the Rule Management Application The tool can modify business logic in two ways By specifying a different rule implementor for a BRBeans rule name By changing variable business rule data 3 1 2 BRBeans framework components The BRBeans framework consists of EJBs APIs and stand alone tools for maintaining business rules The following components comprise the framework gt BRBeans EJBs provide a runtime environment for the framework During the development phase they persist business rule configurations At runtime BRBeans EJBs are responsible for finding and firing BRBeans rules BRBeans EJBs must be deployed with the application that uses them BRBeans Trigger Point framework provides an interface to access BRBeans rules from the rule client To use a BRBeans rule the rule client creates an instance of a TriggerPoint TP object and calls one of the TP object s trigger methods trigger triggerClassifier triggerSituational Then TP object calls the fire method on the RuleImplementor object BRBeans Rule Implementors are Java classes that provide implementation for common business logic such as a number range check These rule implementors are ready for use by rule clients through the BRBeans framework BRBeans Rule implementors can be used as examples for implementing custom business rules The Rule Management Application is a stand alone tool for maintaining BRBeans
145. can see the changes in the total order discount value The total order discount is the sum of the customer level discount and the amount of purchase discount Purchases that are greater than 50 get a 5 discount if they are greater than 75 they get a 7 discount and if they are greater than 100 they get a 10 discount In this example after adding the first item the total order discount is 7 Gold level discount after adding the second item the total discount is 12 the sum of 7 Gold level discount and 5 purchase discount and after adding the third item the total discount is 17 the sum of 7 Gold level discount and 10 purchase discount See Figure 3 11 Shopping Cart Jtem ID Description ltem Price Quantity 000013 Doll_House_Furniture 24 22 1 000017 Magical_Mystery_Maze 39 83 1 000002 Radio_Controlled Plane _ 96 86 1 Order Total 160 94 lt _Gold Discount 7 Total Order Discount 17 Figure 3 11 Testing discount rules implementation This implementation of the discount rule gives us the flexibility to change the discount percentage without changing the rule client Perform these tasks and test the application after each change Expire the second discount rule in the Rule Management Application by changing the end date in the Properties window to some date in the past The status of the modified BRBeans rule is expired as shown in Figure 3 12 36 WebSphere Application Server Enterprise Edition 4 0 A Programmer
146. cation Server Enterprise Edition 4 0 A Programmer s Guide Call HandleErrors ROUTINE NAME End Function HandleErrors ROUTINE_NAME is then called This method uses the error description Err Description to categorize and log the error see Example 7 15 Example 7 15 HandleErrors function in COrderClerk cls Private Sub HandleErrors ByVal RoutineName Dim ejbName Dim ejbNamePos Dim errDescription Const ROUTINE_NAME HandleErrors Case InStr Err Description javax naming NameNotFoundException gt 0 ejbNamePos InStr Err Description Remaining Name ejbNamePos ejbNamePos 15 ejbName Mid Err Description ejbNamePos errDescription The Enterprise Java Bean amp _ ejbName amp _ is not deployed Case InStr Err Description javax ejb FinderException gt 0 Err Number Errors ERRID_NO RECORD_FOUND Case InStr Err Description javax ejb ObjectNotFoundException gt 0 Err Number Errors ERRID_NO_RECORD_FOUND Case Else errDescription Err Description End Select Errors AddError ModuleName MODULE_NAME _ Chapter 7 The ActiveX bridge service 143 RoutineName RoutineName _ ErrorNumber Err Number _ ErrorDescription errDescription _ ErrorSource Err Source End Sub 7 7 Good programming guidelines Keep the interface simple The quickest way to access Java components and resources is by using the Java language Therefore we recommend that the majority of code is written in
147. cation Server has Extended Messaging enabled 64 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Note It is possible to create a new Application Server specifically for use with JMS This enables setting properties on the server in isolation and specifically for the JMS Listener service Keep in mind JMS Listener will run on its own JVM This means that calls to EJBs on other Application Servers will become out of process You must also consider scaling issues with JMS Listener gt gt gt gt How many destinations should it be listening upon How many bean instances should be active How big should the pool be defined for sessions What happens if you define two servers on the same machine both with a listener active Should they share the same destination or interference a problem 5 The final part of the JMS Listener configuration is shown in Figure 4 16 We ensure The classpath for the JMS Listener contains the mq jar and jms jar files supplied with MQSeries The classname for the class that implements the JMS Listener itself is specified The XML configuration file that we wanted to use is specified Fj Edit Custom ServiceExtended Messaging Support Service k 3 oj x General Custom Name lExtended Messaging Support Service Description Extended Messaging Support enables automatic asynchronous deliver of messages to an enterprise application Classpath CABMIMQ
148. ception return specials Rule configuration Start the Rule Management Application if it is not already started see 3 2 1 Setting up the development environment on page 19 Expand the Rule Namespace folder and click the CustomerRules folder You can see four rules for CustomerClassification and three Specials rules CustomerClassification returns one of three values Preferred Gold or Platinum There is a classified Specials rule for each possible return value see Figure 3 14 Rule Browser E 0 x File Edit View Help All Folders Rule Namespace Rules in folder CustomerRules Name a Status_ Classification H E CustamerRules CustomerClassification in effect H E DiscountRules Specials in effect Preferred H E OrderRules 9 Specials in effect Platinum H E ShippingRules Specials in effect Gold H E com off gt 4Rules Manon Figure 3 14 Configuring the classified rules Open the Properties window for each Specials rule In the Classification section on the General tab each Specials rule is classified with a different string Preferred Gold or Platinum On the Implementation tab notice that each rule has different implementation class and initialization parameters specials for each level Chapter 3 The Business Rule Beans service 39 Rule client implementation In WebSphere Studio Application Developer navigate to the getCustomerSpecials method in th
149. changes Example 3 1 Modifying the ibm web bnd xmi file lt ejbRefBindings xmi id EjbRefBinding 4 jndiName brbeans OrderEntry Rule gt lt bindingEjbRef href WEB INF web xml EjbRef_4 gt lt ejbRefBindings gt lt ejbRefBindings xmi id EjbRefBinding_5 jndiName brbeans OrderEntry RuleFolder gt lt bindingEjbRef href WEB INF web xm l EjbRef_5 gt lt ejbRefBindings gt lt ejbRefBindings xmi id EjbRefBinding 6 jndiName brbeans OrderEntry RuleHel per gt lt bindingEjbRef href WEB INF web xm l EjbRef_6 gt lt ejbRefBindings gt 20 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Generate the BRBeans code for deployment i In WebSphere Studio Application Developer open the J2EE Perspective click Perspective gt Open gt J2EE ii Expand the EJB Modules folder iii Right click BRBeansDB2 and select Generate gt Deploy and RMIC Code Make sure three EJBs are selected Rule RuleFolder and Rule Helper iv Click Finish Note For details on importing the BRBeans jar file including the installation for different database types Oracle SQLServer Sybase and Informix see the BRBeans product documentation at http www ibm com software webservers appserv doc v40 aee index html 3 Add several JAR files to OrderEntryWeb classpath These JAR files are needed to compile Web module a From the Navigator View in WebSphere Studio Application Developer select the o 29 5
150. chg ctx JMS The Def command defines a JMS context The chg command changes into the JMS context To display the contents of your current context enter the following command dis ctx Output from the command is shown in Figure 4 8 ER C IBM MQSeries Java bin jmsadmin InitCtx OrderEntry gt dis ctx Contents of InitCtx OrderEntry D JMS javax naming Context 1 Object lt s gt 1 Context lt s gt Binding lt s gt Administered InitCtx OrderEntry gt m Figure 4 8 The current context To delete the context you must be within its parent context and issue the following command Del ctx lt context name gt The JMS destination and other queues The next step is to add information in the namespace under OrderEntry JMS context that binds JNDI names into the physical queues 58 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The JMS destination Qin is defined and bound to a JNDI entry using the JMSAdmin tool The same operation is performed for the output queue Qout While within the OrderEntry JMS JNDI context we execute the following commands Def q Qin Qu Qin Def q Qout Qu Qout q is the JMS queue resource and Qu is the physical MQSeries queue A list of the newly defined JMS resources at the OrderEntry JMS node in the JNDI namespace can be displayed by entering the command dis ctx The output of this command is shown in Figure 4 9 6s C IBM MQSeries
151. client ibm2ejb IF Henning oe corba tools 1 WAS_HOME Enterprise include I include GX c nologo MD Od DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE DUSE_JAVA_EX DORB WebSphere CustomerFactory cpp CustomerFactory cpp 2 Link the tools library and DLL which produce the output Creating the tools lib lib nologo LIBPATH LIBPATH WAS_HOME Enterprise lib LIBPATH lib OUT tools lib def Trace obj Error obj Warning obj MyOrb obj Creating library tools lib and object tools exp linking the tools dll library link NOLOGO INCREMENTAL NO DEBUG LIBPATH LIBPATH WAS_HOME Enterprise lib LIBPATH lib somororm ib somosalm 1ib Vtlib 1ib kernel32 1ib user32 1ib DLL tools exp Trace obj Error obj Warning obj MyOrb obj OUT tools d1 168 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide cd 0E_HOME corba client ibmZ2ejb move 0E_HOME corba tools tools d11 Building the main object and linking the executable The main method is located in the ibm2ejb cpp file Beside the tools and stubs libraries it uses the ProgVals class to read the program arguments The makefile ibm2ejb file executes the following final steps 1 Compile the main and the ProgVals object The output is x Generating the ibm2ejb obj object cl 1 0E_HOME corba client ibm2ejb 1 0E_HOME corba tools 1 WAS_HOME Enterprise include I include GX c nologo MD Od DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE DUSE_JAVA
152. communicate with the OrderEntry application by using the ActiveX bridge service Since the BPBeans service is just a technical preview we are not going to concentrate on the applicability of the service for the OrderEntry application Rather we highlight the benefits of the BPBeans service and outline the steps in developing a BPBeans enabled application 2 1 1 The ABC Company The OrderEntry application is used by a fictitious company called ABC Company The ABC Company is a wholesale supplier with one warehouse and 10 sales districts Each district serves 3 000 customers 30 000 total customers for the company The warehouse maintains stock for the 100 000 items sold by the Company The ABC Company also operates a fulfillment center that is responsible for the shipment of the orders Figure 2 1 illustrates the company structure warehouse district and customer District 2 30K Customers District 10 30K Customers District 1 30K Customers Figure 2 1 The company structure 6 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 2 1 2 The ABC Company database The Company runs its business with a database This database is used in a mission critical online transaction processing OLTP environment The database includes tables with the following data vvvvvy District information next available order number tax rate and so on Customer information name address telephone
153. context in WebSphere Application Server Each piece of data can be accessed separately so if the type or length of the data changes only those methods that actually use that particular piece of data are affected by the change In addition the ability to modify the data in WorkArea can be controlled by setting modes for each piece of data The information in WorkArea consists of a set of properties a property consists of a key value mode triplet The key value pair represents the information contained in the property the key is a name by which the associated value is retrieved The mode determines whether the property can be removed or modified The applications access the WorkArea facility by using the com ibm websphere workarea UserWorkArea interface It contains nine methods that we discuss throughout this chapter WorkArea has an important characteristic The data can only be passed one way from the caller to the remote method If the remote method makes changes to the data the changes are never seen by the caller A remote method can be another serviet or a method in the remote interface of an EJB Even if the servlet or bean resides in the same JVM the call is still considered remote It is important to remember this characteristic when designing applications that will use WorkArea For the remainder of this chapter we refer to a piece of data in WorkArea as a property 5 1 1 WorkArea scope 92 An important concept to under
154. count factor as a separate rule and provide discount values as rule initialization parameters We can add new discount factors by creating new rule implementors and configuring them in the Rule Management Application We can also change discount values in the Rule Management Application Neither of these tasks requires changes in the rule client WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Base rules implementation In WebSphere Studio Application Developer expand the OrderEntryWeb folder In the source rules folder you can find implementations of two base rules gt DiscountByLevel gt DiscountByTotal DiscountByLevel implementation returns a discount percentage based on a customer level Rule implementor initialization parameters include amounts required to qualify for each customer level and discount values for each customer level Implementation of the fire method is shown in Example 3 5 implementation of the init method is similar to Example 3 2 on page 27 Example 3 5 Implementation of the DiscountByLevel fire method public Object fire TriggerPoint tp Object target IRuleCopy rule java lang Object parms throws BusinessRuleBeansException int discount 0 int amountYTD 0 if initialized In all discount rules the first parameter is the amount of purchase The amount of purchase is not used by this rule The second parameter in the array is the amount of YTD purchases amount
155. d files and directories you can call cd 0E_HOME corba server ejb2orbix nmake f makefile ejb2orbix cleanejb The makefile calls ant in order to complete the build 1 The IDL compile produces the following output x Compiling the ejb client stubs ant buildfile ejb build_client_stubs xml Buildfile ejb build_client_stubs xml build idl echo Compiling IDL sources exec Parsing CreditInstitute id exec done CreditInstitute id exec exec Generating com exec done com 2 From the compilation of the Java classes we only show fragments of the output build_classes echo Compiling java sources exec parsing started com ibm itso roch credit _CreditInstituteImp Base java exec parsing completed 271ms exec parsing started com ibm itso roch credit _CreditInstituteStub java exec parsing completed 180ms exec loading C IBM WebSphere AppServer java jre lib rt jar org omg CORBA_2_3 portable ObjectImp1 cla ss exec loading C IBM WebSphere AppServer java jre lib rt jar org omg CORBA portable ObjectImp class exec checking com ibm itso roch credit PersonNotFoundHolder exec wrote com ibm itso roch credit PersonNotFoundHolder class exec checking com ibm itso roch credit ROOT_IOR_ FILENAME exec wrote com ibm itso roch credit ROOT_IOR_FILENAME class exec total 8913ms 3 The classes are packaged into a JAR file The output is build_jar jar Building jar F Hennin
156. dOnly void set String key java io Serialazable value PropertyModeType mode throws NoWorkArea NotOriginator PropertyReadOnly java io Serializabel get String key PropertyModeType getMode String key void remove String key throws NoWorkArea NotOriginator PropertyFixed The following methods are public methods that are available on WorkAreas gt retrieveAllKeys Returns an array of Strings that contain the names of all properties in WorkArea If no WorkArea was found the method returns null If WorkArea contains no properties for example WorkArea was created but no properties were set the method returns an array of zero length gt getMode Returns a PropertyModeType indicating the mode for the property with the given name Chapter 5 The WorkArea service 101 5 3 5 Putting other objects in WorkArea It is possible to store objects other than Strings in WorkArea These objects must implement the java io Serializable interface Strings and some other commonly used objects already implement Serializable This interface requires two methods writeObject and readObject The writeObject method writes the object to an ObjectOutputStream and readObject method reads the object from an ObjectInputStream This is usually implemented by writing and reading the individual fields of the object For objects that only contain only primitives the default implementation can be used See the API documentation for the java io Serial
157. dd to customer collection Call Customers Clear Dim TempCustomer As Variant Do While CustomerList hasMoreE ements TempCustomer CustomerList nextElement Set CustomerObject Customers Add Trim TempCustomer CustomerData custID _ Trim TempCustomer CustomerData FirstName _ Trim TempCustomer CustomerData LastName _ rim TempCustomer CustomerData MiddleInitials _ rim TempCustomer CustomerData Address1 _ Trim TempCustomer CustomerData Address2 _ Trim TempCustomer CustomerData City _ rim TempCustomer CustomerData State _ rim TempCustomer CustomerData ZipCode Loop Set GetAl Customers Customers Exit Function ErrorHandler Call HandleErrors ROUTINE NAME End Function There are some other aspects of using arrays gt In Java all the elements of an array must be of the same type For this reason a Variant array must contain all elements of the same type if it is to be included as a parameter ina Java method call gt Java arrays are always zero based meaning the first element is always at position 0 when it is received in an automation container gt Nested or multi dimensional arrays are treated as zero based multi dimensional arrays in Visual Basic or VBScript 7 5 6 Threads The ActiveX to EJB bridge supports both free threaded and apartment threaded access and implements the Free Threaded Marshaler to work in a hybrid environment such as Active Se
158. derEntrySenvlet ApplicationMgr com ibm itso roch wasaejb OrderEntryClerk temsViewBean com ibm itso roch cpwejb interfaces OrderDetail OrderConfimation isp Customer has i made selections checkOut ede n i lookup EJB S getCugtomer setCustomer i elOrderLines a t getSelecteditems create gii placeOrder setOrerlD U display JSP i Figure 2 4 Order check out process The checking out functionality is embedded into the placeOrder method of the com ibm itso wasaejb OrderPlacement session EJB not shown in the diagram This method is called from the com ibm itso roch wasaejb OrderEntryClerk session EJB 2 2 OrderEntry application database layout The sample application uses the following tables of the database District Customer Order Order line Stock Item catalog vvvvvy The following sections describe in detail the layout of the database 2 2 1 Tables The District table keeps information related to each district The primary use of this table in the application is to store the next available order number Table 2 1 shows the layout of the District table Table 2 1 District table layout Dstrct C e 10 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide oxston e oww O Primary Key DID and DWID The Customer table is used to store customer information Th
159. e new CosNaming Name count the number of parts int i int partNo 1 for i nameString find sep i nameString npos i nameString find sep i 1 partNot name gt ength partNo int start 0 int end j for j 0 j lt partNo j end nameString find sep start token nameString substr start end start t printin found token token name j id name j kind start end 1 CORBA string_dup token c_str CORBA string_dup return name Creating a customer After CustomerHome is instantiated all methods of the CustomerHome can be used This section covers the creation of a Customer object The other calls are similar Example 8 4 shows the important parts of the CustomerFactory s createBean method Example 8 4 Creating a customer CustomerWrapper CustomerFactory createBean string customerID string foreName string lastName string phone Customer_var bean NULL bean _customerHome gt create__CORBA_WStringValue_ CORBA_WStringValue__CORBA _WStringValue__CORBA_WStringValue MyOrb stringToWStringValue customerID c_str MyOrb stringToWStringValue foreName c_str MyOrb stringToWStringValue lastName c_str MyOrb stringToWStringValue phone c_str if CORBA is_nil bean err printIn Create returned nil Chapter 8 The CORBA services 173 return CustomerWrapper bean char MyOrb wstringValueToString CO
160. e ApplicationMgr class the OrderEntryWeb source application folder The classifier rule in this method is the CustomerClassification rule we created earlier in this chapter Specials is the name of the base rule or rules that is invoked based on the value returned from CustomerClassification In the getCustomerSpecials method see Example 3 10 we populate the required parameters for both the classifier rule and the classified rule fire the classifier and classified rules and process the results Note that only the results of the classified rule are returned Example 3 10 Implementation of the getCustomerSpecials method Classifier rule requires one parameter the amount of YTD purchases Object classifierParams new Integer amountYTD Specials rule does not require any parameters Object classifiedParams null Rule Names String classifierName CustomerRules CustomerClassification String classifiedName CustomerRules Specials Object result tp triggerSituational this classifiedParams classifierParams classifiedName classifierName if result null itemsViewBean setApplicationError The rule returned null yelse Rule successfully called Object resultArray Object result The first element is the array of specials Object specials Object resultArray 0 for int i 0 i lt specials length i String special String specials i custSpecials addE ement s
161. e Management Application The disadvantage of firing the rules locally is the requirement to install rule implementors on each client system that uses BRBeans rules The best performance is achieved by using the client side cache and local firing location Creating database indexes Performance can be improved by creating an index for a rule name column in the rule definition table In the BUSRULES database provided with OrderEntry application business rule data is stored in the BRBEANS_RULE table Creating an index for the rulename column in this table can improve performance of queries searching for a rule name Note For more information on improving performance see the product documentation at http www ibm com software webservers appserv doc v40 aee index html 3 4 Deployment The BRBeans framework uses a database to persist BRBeans rule data You can create a separate database to maintain rule data or create tables in the main database used by the application All EJBs accessed in the same transaction must specify the same isolation level Using a different database for business rules removes this restriction because application EJBs and rule EJBs are accessed in different transactions In our example we used a separate database to maintain business rule data BUSRULES BRBeans should be deployed as a part of the application EAR file We completed this step while setting up BRBeans development environment see 3 2 1 Setting up the
162. e Rule Management Application gt fire This method implements business logic and returns results of an algorithm to the caller The TriggerPoint object invokes the fire method from the rule client passing parameters expected by the rule implementation gt getDescription This method returns a string containing a description of the Rulelmplementor Configuring business rules The Rule Management Application is used to configure and maintain BRBeans rules The tool gives the ability to perform the following tasks gt Create a new BRBeans rule definition BRBeans rule folder and name used to look up the BRBeans rule by the TriggerPoint object BRBeans rule start and end date BRBeans rule type Classifier non classifier or classified BRBeans rule implementor Java class Initialization parameters for the rule implementor Dependent BRBeans rules gt Modify a BRBeans rule definition gt Export or import BRBeans rule definitions which are created in XML format Using Quick Copy in the Rule Management Application The Rule Management Application provides the Quick Copy function to replace the existing BRBeans rule with a new one on a specified date The Quick Copy function creates a copy of the existing rule and allows you to change the BRBeans rule start date and the initialization parameters Once the copy of the BRBeans rule is created the end date of the original rule is set to the start date of the ne
163. e Time User Identifier Put Application Name Data Length Message D Sy 10 27 2001 4 41 26 PM itscid20 Serverjavaijrebinava exe MQHRF2 156 General Report Context identifiers Segmentation Data Message Data Length 156 Format eRe CCU Coded Character Set ID 819 Encoding 273 Message Data All available messages on the queue have been br Hexadecimal Text 64 3E 6A 6D 73 5F 74 65 78 74 3C 2F 4D 73 64 3E 3C 2F 6D 63 64 3E 20 20 lt med gt 00 00 00 24 3C 6A 6D 73 lt tjms 3E 3C 44 73 74 3E 71 75 gt lt Dst gt qu 65 75 65 3A 2F 2F 2F 51 eue Q 6F 75 74 3C 2F 44 73 14 li 3E 3C 2F 6A 6D 73 3E 20 Refresh Figure 4 21 Confirming the test message was successfully handled 4 3 JMS publish subscribe Publish subscribe can be considered an extension of the point to point messaging model JMS destinations are no longer queues but topics Any application that needs to get a message of the topic has to register with it In addition to the components in the point to point model the publish subscribe model introduces MQSeries message broker A Java application creates a connection to a topic and publishes a message there The broker filters the message to all listeners registered with that topic From here it is similar to the point to point model JMS Listener then invokes message beans in accordance with its XML configuration file see Figure 4 22 76 WebSphere Application Server Enterprise
164. e aie a Qaida Hale eh pe aba es 95 2 4 Using WorkAle ai ni igsgis pasi Sate A wade alates Yada endear ae a 95 5 2 5 Terminating WorkArea ar O oV ERE eee ae 96 5 3 Beyond the example 1 0 0 ee eee ete e nes 96 5 3 1 Using property modes to protect information 2 2000000ee 97 5 3 2 Nested WorkAreas is sis wiped da Qcntd Hole ee Wie Ra wea ee Eta 97 5 3 3 Changing the modes 0 cece ka EKAN EEE Eika 101 5 3 4 Other methods defined by the UserWorkArea interface 101 5 3 5 Putting other objects in WorkArea 0 00 eee 102 5 3 6 CORBA considerations 0 0 0 0c tenes 102 5 4 Configuring the WorkArea service in WebSphere Application Server 102 5 4 1 Ensuring the WorkArea service is enabled in the Administrative Console 102 5 4 2 Setting maximum send and receive Size 2 ee ee 103 5 4 3 Passing WorkArea through multiple WebSphere Application Servers 104 Chapter 6 The Internationalization service 02 ee eee eee 105 6 1 The Internationalization service overview 00 0 eee eee 106 6 1 1 Computers located in different locales 0 0 0 0c ee eee 106 6 1 2 Computers located in different time zones 0 0000 eee eee 106 6 1 3 The Internationalization service solution 0000 eee 106 6 2 Internationalization context 0 ce eee 107 6 2 1 The information in the internationalization contex
165. e propagates the default values that are associated with the clients JVM at that time Server side Internationalization SSI policy EJB application components deployed within J2EE server side containers are subject to the Server side Internationalization policy SSI specifies how internationalization context propagates across the Web and Enterprise JavaBean container boundaries and defines access privileges to internationalization context within contained application components In SSI server side application components always run under the caller s internationalization context The service associates the context of an incoming business method request to the thread on which that method will execute The incoming caller context is associated as both the caller and invocation context for that method and persists until the method returns This policy is applied directly to Enterprise JavaBean methods SSI is defined in a different way for the servlet methods such as doGet or doPost because they are invoked using Web browser clients On incoming servlet requests from a Web browser client the Internationalization service associates the list of locales propagated by the browser within the HTTP header and the server s default time zone to the thread on which the servlet service method will execute The client s time zone is not propagated from the browser to the server On the remote method calls to EJBs originated from either a servlet or
166. e search of the customer is done based on the customer ID column To simplify the OrderEntry application we decided not to implement additional customer search functions Table 2 2 shows the Customer table layout Table 2 2 Customer table layout CSTMR eioare ower eons ite Chapter 2 Overview of the OrderEntry application 11 Primary Key CID CDID and CWID The Order table stores the order related information The information in the Order ID column is used to key the order lines Table 2 3 shows the Order table layout Table 2 3 Order table layout ORDERS emo T fs Ec E e Se foo C a C C a C C eed Primary Key OWID ODID and OID The Order Line table stores information about each item being ordered The Order ID column keys each order line to the corresponding order Table 2 4 shows the Order Line table layout Table 2 4 Order Line table layout ORDLIN Ca C e C E C E Cranowr its C e e df C e e C a e Pereo oonan O O E Primary Key OLWID OLDID OLOID and OLNBR 12 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The Item table plays a role of the catalog in the OrderEntry application Table 2 5 shows the layout of the Item table Table 2 5 Item table layout ITEM mo fee e e Primary Key IID The Stock table keeps the inventory of the items up to date Table 2 6 shows the layout of the Stock table Table 2 6 Stock table layout Stock mw eee e
167. e set method to override an existing property or to add a new property anywhere outside the OrderEntryServlet we would get a NotOriginator exception We may only use the get method to read values from WorkArea outside the OrderEntryServlet To override a property in an existing WorkArea that was not originated in the current servlet or bean we must create a nested WorkArea A nested WorkArea is created the same way as the original WorkArea was with the begin method Example 5 7 is identical to the code for creating a new WorkArea We pass the serviet name to identify the nested WorkArea with its creator Chapter 5 The WorkArea service 99 Example 5 7 Creating a nested WorkArea import com ibm websphere workarea Context ctx getInitialContext UserWorkArea workArea getWorkArea ctx workArea begin AnotherServlet Using a nested WorkArea Using the nested WorkArea is the same as using the original WorkArea The nested WorkArea has all the properties of the original WorkArea plus any properties added in the new WorkArea The difference is that in the new WorkArea we can override the properties and values of the original WorkArea To override the value of an existing property in the original WorkArea call the set method passing the name of the existing property and the new value This actually creates a new property in the new WorkArea that overrides the property in the original WorkArea However to the current scope it looks a
168. e to the needs of the most demanding customers IBM delivers the new WebSphere Enterprise Services that are part of WebSphere Application Server Enterprise Edition Version 4 0 This IBM Redbook discusses the new WebSphere Enterprise Services and shows the best practices for using the services in the applications The target audience for this book is the I T specialist and application developers Some parts of the book such as Business Rule Beans and Business Process Beans will be of particular interest to business domain experts SG24 6504 00 ISBN 0738423998 ye E Redbooks INTERNATIONAL TECHNICAL SUPPORT ORGANIZATION BUILDING TECHNICAL INFORMATION BASED ON PRACTICAL EXPERIENCE IBM Redbooks are developed by the IBM International Technical Support Organization Experts from IBM Customers and Partners from around the world create timely technical information based on realistic scenarios Specific recommendations are provided to help you implement IT solutions more effectively in your environment For more information ibm com redbooks
169. e transaction will cause the message to remain on the destination The commit of the transaction will cause the message to be removed from the destination Use the application assembly tool or WebSphere Studio Application Developer to configure the onMessage method of the message bean to support the transactional behavior that you want For future compatibility with the EJB2 0 specification message beans specify either bean managed transactions BMT or container managed transactions CMT with a transaction behavior of TX_NOT_SUPPORTED or TX_REQUIRED When transaction handling is not specified the message is read from the destination queue without being part of a global transaction For transactional behavior the WebSphere specific JMS XA connection factories wsqcf for queue and wsicf for topic must be defined in the JNDI name space using the JMSAdmin tool For destinations not requiring global transaction support the JNDI name space can be configured using the non XA JMS connection factories such as qcf for queue and tcf for topic With non WebSphere XA connection factories JMS calls issued on the destination are not part of WebSphere Application Server transactions Also JMS resources are not recovered if the server fails Bean managed transactions BMT The configuration file should not specify transactions for a message bean that uses bean managed transactions It is not really a restriction but more of a recommendation The s
170. e transactional depending upon the method properties 4 4 2 JMS Listener threads and MaxSessions MaxSessions is a listener attribute within the listener stanza of the XML configuration file This setting has a direct impact on overall system performance Each application server that has Extended Messaging configured and at least one JMS Listener defined in its XML configuration file has a pool of threads defined internally These threads take messages off of the queue obtain the associated message bean instance and call the onMessage method for that bean This pool of threads is referred as the Server Session Thread Pool The Server Session Thread Pool begins with five threads and has a maximum sustained thread pool size of 20 Once the maximum pool size is reached any additional threads used are not pooled they are disposed It is likely that the next release of WebSphere will allow configuration of this pool Only one Server Session Thread Pool exists for a WebSphere Application Server regardless of how many listener stanzas exist for a given server In the simple case where each WebSphere Application Server has one listener stanza the current values for MaxSessions is sufficient In a more complex case where the number of listener stanzas is greater than one each listener competes for the same threads from the Session Thread Pool For example if you defined 10 JMS Listeners on average there are only two Server Session Thread Pool t
171. eOrderTotal if result null jtemsViewBean setApplicationError The rule returned null else Rule successfully called Object resultArray Object result The first element is the array of specials orderTotal Float resultArray 0 jtemsViewBean setOrderTotal orderTotal floatValue Testing the application To see the results of the rule implementations test the application 1 Export and install the OrderEntry application if needed 2 In the WebSphere Administrative Console start OrderEntryServer if it is not already started 3 Bring up application home page http localhost lt port_number gt OrderEntry index htm 4 Select New Order 5 Type in the customer ID which is 0002 and click the Submit button 6 Add several items 7 Select the shipping type and click Check Out The next page displays the total order amount as shown in Figure 3 19 the discount value may be different depending on the total amount of purchase Order Information Onder Number 3611 Total Order Amount 63 14 Discount received 15 Figure 3 19 Total order amount Chapter 3 The Business Rule Beans service 45 Other usage of dependent rules Dependent rules can be used to encapsulate a validation process Different validation functions such as checking customer balance credit limit and item availability can be implemented as separate business rules that return an object type of Boolean or Co
172. eans components during the development phase At runtime the rule client invokes BRBeans rules using the TriggerPoint object Each BRBeans rule configured in the Rule Management Application is represented as an EJB at runtime After the BRBeans rule is located the framework fires the actual implementation and returns results to the rule client Figure 3 2 shows the interaction of BRBeans components a A Rule Client execute the rule EJB Servlet Java class return result WebSphere he Figure 3 2 Runtime interaction of BRBeans components Chapter 3 The Business Rule Beans service 17 3 1 3 Identifying business rules Business rules are policies used by companies in conducting business practices These policies may be specific to a company or may come from an outside regulatory agency A business rule usually contains some variable information reflecting a change in a business process For example consider the following business rules gt Example 1 If a customer has purchased 500 worth of products YTD then the customer qualifies for the Preferred Club This business rule is an example of an internal business policy The balance required to qualify for the Preferred Club may change In addition the company may decide to add additional customer classifications Gold Club and so on gt Example 2 If the total order amount is greater than 100 then provide a 10 percent discount T
173. ecific situation there is no guarantee that the same or similar results will be obtained elsewhere Customers attempting to adapt these techniques to their own environments do so at their own risk Any pointers in this publication to external Web sites are provided for convenience only and do not in any manner serve as an endorsement of these Web sites Copyright IBM Corp 2002 vii IBM trademarks The following terms are trademarks of the International Business Machines Corporation in the United States and or other countries e logo Redbooks Logo Cd IBM Redbooks AIX S 390 Balance Sequent CICS SP DB2 TXSeries Encina VisualAge IBM WebSphere Informix Approach MQSeries Notes Perform Other company trademarks The following terms are trademarks of other companies C bus is a trademark of Corollary Inc in the United States and or other countries Java and all Java based trademarks and logos are trademarks or registered trademarks of Sun Microsystems Inc in the United States and or other countries Microsoft Windows Windows NT and the Windows logo are trademarks of Microsoft Corporation in the United States and or other countries PC Direct is a trademark of Ziff Communications Company in the United States and or other countries and is used by IBM Corporation under license ActionMedia LANDesk MMX Pentium and ProShare are trademarks of Intel Corporation in the United St
174. eference that can be exchanged between two ORBs Another way to export object references is to write them to files The client environment contains the client application code the stub and the client ORB The stub is a proxy object for the servant which behaves to the client code like a local object It does the marshalling translates method call for network transport and directs the requests to the ORB When a client wants to call a method on a servant object it first locates an object reference via the naming service With this object reference the stub object is instantiated Then the client application can invoke the method in the servant CORBA development Figure 8 3 shows an overview about the development steps for CORBA IDL D C ee IDL IDL Compiler Compiler Client Server Developer Developer ae cc Client Server a ZI Stub Stub N J Xa J Client Side Server Side Figure 8 3 CORBA development steps To develop a CORBA application you have to perform the following steps 1 Define the IDL interfaces Identify the objects required by the application and define their public interfaces in IDL WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 2 Compile the IDL files with an IDL compiler This creates the client and server stub files Depending on the IDL compiler you may already get a dummy implementa
175. ency helper function Visual Basic 6 0 cannot properly handle 64 bit integers like Java can as the Long data type Therefore Visual Basic uses the Currency type which is intrinsically a 64 bit data type The only side effect of using the Currency type the Variant type VT_CY is that a decimal point is inserted into the type Example 7 6 shows a method to extract and manipulate the 64 bit long value in Visual Basic Example 7 6 The Currency helper functions Currency Helper Types Private Type MungeCurr Value As Currency End Type Private Type Munge2Long LoValue As Long HiValue As Long End Type Currency Helper Functions Private Function CurrToText ByVal Value As Currency As String Dim Temp As String L As Long Temp Format Value 0000 L Len Temp Temp Left Temp L 5 amp Right Temp 4 Do While Len Temp gt 1 And Left Temp 1 0 Temp Mid Temp 2 Loop Do While Len Temp gt 2 And Left Temp 2 0 Temp amp Mid Temp 3 Loop CurrToText Temp End Function Private Function TextToCurr ByVal Value As String As Currency Dim L As Long Negative As Boolean Value Trim Value If Left Value 1 Then Negative True Value Mid Value 2 End If L Len Value If L lt 4 Then TextToCurr CCur IIf Negative 0 0 amp _ Right 0000 amp Value 4 Else TextToCurr CCur IIf Negative amp _ Left Value L 4 amp amp Right Val
176. end the com ibm bpb base ActivityBase class Depending on the type of port Activity uses you need to implement a different interface in Activity Input Port implement the com ibm bpbeans InputPortListener interface e InOut Port This port is designed to receive a message and send a response Implement the com ibm bpbeans InOutPortListener interface When the message arrives the requestArrived method is invoked One of the parameters in this method is of type com ibm bpbeans ReplyToken This parameter is used to send the reply e Outin Port This port is opposite to InOut Port First a message is sent then Activity waits for a response It would be valid to assume that Activity should implement the com ibm bpbeans OutInPortListener interface However to receive a response Activity has to implement the com ibm bpbbeans ResponseListener interface An example of using this type of port is shown in Example 9 1 e Output Port You use this port if Activity needs just to send the message without expecting a reply You don t need to implement any interface in Activity unless Activity needs to know when the message was really sent In this case Activity should implement the com ibm bpbeans QutputPortListener interface Also code all business logic for this Activity Resource Resource has to implement the com ibm bpbeans Resource interface or it can extend the com ibm bpb base ResourceBase class Code all business l
177. ent cannot initialize the JVM The following sections offer a brief description of the major components of the Visual Basic Order Entry Client ActiveX_XJBHelpers This module should be added to any Visual Basic application that is to be modified to take advantage of the ActiveX to EJB bridge The generic methods are used to initialize the JVM and client container and obtain references to EJB Home Interfaces XJBlnit Creates and initializes the JVM XJBGetJ2EEClientContainer Gets the J2EE Client Container object XJBGetEJBHome Gets the Home EJB Object XJBPutProperty Adds a string key value to a Java Properties object XJBGetProperty Gets a string key value to a Java Properties object XJBGetEnvEntry Gets an environment entry from the J2EE client container namespace vvvvvy modMain The main method of this module is the first method to be called when the application is run It is responsible for initializing the global g Config object and displaying the options window Class modules This section presents the custom built class modules They represent the Visual Basic part of the application ActiveX_EJBHomeRef This class is used to hold a reference to all the EJB Home Interfaces It uses XJBGetEJBHome in the ActiveX_XJBHelpers module during initialization It is referenced via the g_Config object which ensures that it is initialized ActiveX_Config This class has three roles gt Holds the XJB JClassFactory object throughou
178. erHome As Object oArgsb AddObject java lang Object oJavaObj oArgsb AddObject java lang Class oXJB FindClass com ibm itso roch wasaejb CustomerHome Set clsPortRemObj oXJB FindClass javax rmi PortableRemoteObject Set oCustomerHome clsPortRem0bj narrow oArgsb 1 1 1 gt Since the client JAR file can be packaged in the EAR file along with the EJB archive and WAR files everything can be distributed to the clients and servers in the same file The price for using this service is the time taken to initialize the container and launch the client around 5 to 8 seconds Note You can find more information on J2EE client containers in 4 7 Java Clients in the WebSphere Version 4 InfoCenter at http www ibm com software webservers appserv doc aee index html 7 4 2 No client container approach The other approach is to run the client application inside a standard JVM but provide the JVM with the resource references needed to call the EJBs and server side services The disadvantage of this approach is that the references have to be passed directly to the JVM when instantiating the javax naming InitialContext object and the application code will be more substantial Example 7 3 shows the code for looking up the Customer Entity EJB home interface without a client container Chapter 7 The ActiveX bridge service 129 Example 7 3 Example code to obtain an EJB reference without a client container Dim p As Object Set p oX
179. ers These components are discussed in the following section 4 3 2 MQSeries message broker To alleviate the complexity of a multiple queue manager topology MQSeries introduces the concept of message brokers with the MQSeries Integrator product Chapter 4 Extended Messaging Service 77 The message broker responsible for distributing incoming messages from a JMS destination must be started on a command line as shown in Figure 4 24 E CAIBM IBM gt strmgqbrk QSeries message broker started for queue manager p23bk66h IBM gt Figure 4 24 Starting MQSeries message broker It is installed from support pack MAOC Note The installation instructions for the support pack are contained in MQSeries Using Java SC34 5456 They are also available from the MQSeries Web site http www ibm com software ts mqseries txppacs ma0c html 4 3 3 The JMSAdmin tool The JMSAdmin tool relationship to WebSphere Application Server and MQSeries is shown in Figure 4 25 It performs the same role as with the point to point model JMS destination queues are replaced by JMS destination topics JMS Provider JMSAdmin MQ WebSphere AS WAS TCF Definitions wstcf correlation Websphere TopicConnectionFactory JNDI Entry correlation TCF Definitions tcf TopicConnectionFactory JNDI Entry JNDI Context Definitions ctx Topic JMS Definitions t correlation Topic
180. ervice QoS 2 3 error handling 142 exception 142 exception handling 86 expired rule state 25 Extended Messaging Service 3 51 extended messaging support 52 F filtering strategy 25 35 finding strategy 24 35 firing location 26 47 firing strategy 25 fixed mode 97 G genie 191 199 globalization 4 H handling arrays 140 IBM Encina 2 IBM MQSeries 2 IBM TXSeries 2 IDL 166 178 191 200 202 IDL compiler 157 162 201 idigen 200 IIOP Internet Inter ORB Protocol 154 in effect rule state 25 instance cluster process 214 integration and adaptability 4 Interface Definition Language IDL 155 internationalization caller 109 client side 111 interface 109 invocation 110 server side 111 internationalization context 107 caller context 108 Client side Internationalization CSI policy 108 invocation context 108 management 111 Server side Internationalization SSI 108 time zone 107 types of context 107 Internationalization context management 111 Internationalization service 3 105 binding to 112 configuring the programming environment 116 enabling for application server 114 enabling internationalization context within EJB Java application client 116 Internationalization interface 109 InvocationInternationalization interface 110 overview 106 retrieving caller internationalization context 113 retrieving the invocation internationalization context 114 setting invocation locale and time zone 117 solution 106
181. es classes for Java Message Service http www ibm com software ts mqseries txppacs ma88 html MQSeries Publish Subscribe http www ibm com software ts mqseries txppacs ma0c html Using Sybase PowerBuilder with the WebSphere Application Server Enterprise Edition Version 4 ActiveX to EJB Bridge http www7b boulder ibm com wsdd library samples powerbuilder htm The Object Management Group OMG Web site http www omg org VisiBroker for C 4 5 installation guide http www borland com techpubs books vbcpp vbcpp45 framesetindex html VisiBroker 4 x for C download Web page http www borland com visibroker download vbcpp4x_steps html Orbix 2000 2 0 Documentation Web page http www iona com docs orbix2000 2 0 index html Orbix E2A Enterprise Edition evaluation form http www iona com forms asp_enterprise_eval_form htm 2002 233 gt IONA Orbix 2000 Administrator s Guide http www iona com docs orbix2000 2 0 admin_cpp htm1 index htm gt IONA Orbix 2000 Programmer s Guide Java version http www iona com docs orbix2000 2 0 pguide_java html index htm gt IONA Orbix 2000 Code Generation Toolkit Programmer s Guide http www iona com docs orbix2000 2 0 codegen html index htm gt IONA Orbix 2000 Programmer s Guide Java version http www iona com docs orbix2000 2 0 pguide_cpp html index htm gt Ant the Jakarta project Web site http jakarta apache org ant index htm gt Ant user manual http jakarta apache
182. ess Permissions Unload C None Script Execute including script Cancel Figure 7 6 Windows NT Properties window for an ASP application Isolating each ASP application If there is more than one JVM to which different ASP applications have to connect each application has to run in its own process The way to achieve this is to set the Application Protection variable in the ASP Application properties to High Isolated in Windows 2000 as shown in Figure 7 5 or set as an isolated process in Windows NT Figure 7 6 Adding the WebSphere Client JRE to the system PATH At the point when the ASP application calls X B nit on the XJB JClassFactory object the JRE runtime directories have to be on the system path so the Java DLLs can be found Since ASP applications don t have an individual PATH the following addition must be made to the system PATH before the application is run JAVA_HOME bin JAVA_HOME bin classic Here JAVA_HOME is where the home of the WebSphere Client JRE for example C WebSphere AppClient java jre This addition to the system PATH is made in the SetUpCmdLineXuB batch file but this is not run for ASP applications A result of adding the JRE runtime to the system PATH is that the same JVM version will be used for all the ASP applications You must reboot the system running the Internet Information Server after you change the system s PATH 146 WebSphere Application Server Enter
183. est to business domain experts The team that wrote this redbook This redbook was produced by a team of specialists from around the world working at the International Technical Support Organization ITSO Rochester Center Aleksandr Nartovich is a Senior I T Specialist in the IBM ITSO Rochester Center He joined the ITSO in January 2001 after working as a developer in the IBM WebSphere Business Components WSBC organization During the first part of his career Aleksandr was a developer in AS 400 communications Later he shifted his focus to business components development on WebSphere Aleksandr holds a degree in Computer Science from the University of Missouri Kansas City as well as a degree in Electrical Engineering from Minsk Radio Engineering Institute You can reach Aleksandr at alekn us ibm com Keith Bennett works as an IT Specialist in IBM Global Services UK He has worked for IBM for two years in developing e business applications in the financial sector using the WebSphere platform He holds a degree in Physics from Oxford University You can reach Keith at BENNETTK uk ibm com Henning Burgmann is an Advisory I T Specialist with IBM Global Services in Cologne Germany He has several years of experience in large service projects in the telecommunications industries His areas of expertise include object oriented development with C and Java focussed on distributed applications using DCE and CORBA as middleware He has one and
184. ey_Imp1 ckey gt primaryKey key return ckey CORBA ValueBase com_ibm_itso_roch_wasaejb_CustomerKey_factory asValueBase void v 7 Provide the additional class CustomerKey_factory_init and instantiate it in CustomerKey_I cpp This class is responsible for the registration of the factory with the ORB return CORBA ValueBase com ibm itso roch wasaejb CustomerKey v class CustomerKey_factory_init public CustomerKey_factory_init CORBA ORB_ptr _vtlibOrb int _argc 0 CORBA ValueFactoryBase var retfact CORBA ValueFactoryBase_ var fact Get access to the ORB _vtlibOrb CORBA ORB_init _argc NULL DSOM Create a CustomerKey factory fact new com_ibm_itso_roch_wasaejb_CustomerKey_factory retfact _vtlibOrb gt register_value_factory const_cast lt char gt CustomerKey CustomerKey_RID fact in s Static instantiation of the class static CustomerKey_factory_init __theCustomerKey_factory_init For a detailed description about how to build a valuetype see the WebSphere InfoCenter navigate to Enterprise services gt Corba support gt Creating your own C valuetypes at http www ibm com software webservers appserv doc v40 aee index html Using the CustomerKey valuetype The previous section showed how to create the CustomerKey valuetype This section shows how to instantiate and use it The CustomerKey object is needed as a paramete
185. f this BRBeans rule should return java lang Integer Configure the HolidayDiscount rule in the Rule Management Application with the same name as other discount rules CalculateDiscount When you run the application the discount percentage changes because the discount value is a sum of the discounts returned from three BRBeans rules Using trigger point strategies To get a better understanding of the use of strategies in the BRBeans framework modify the filtering or the combining strategy of the TriggerPoint object For example the getFirstCustomerDiscount method in ApplicationMgr uses Return First combining strategy see Example 3 8 When the TriggerPoint object is configured with this strategy the results of the first rule matching the specified name DiscountRules CaclulateDiscount are returned Since the rule is guaranteed to return one result only we handle the result object differently than in the getOrderDiscount method In the latter case the results of the rule with DiscountByLevel implementation are returned because this rule has the highest precedence The BRBeans rule precedence is specified on the Other tab of rule Properties window in the Rule Management Application Chapter 3 The Business Rule Beans service 37 Example 3 8 implementation of getFirstCustomerDiscount method public void getFirstCustomerDiscount int purchaseAmount int amountYTD throws Exception Create new trigger point TriggerPoint tp new Trigger
186. formation about using the launchC1ient utility 6 4 3 Configuring the programming environment The java util and com ibm websphere il8n context packages contain all classes necessary to use the Internationalization service within an EJB application Classes that are specific to the Internationalization service reside in the WAS_HOME e lib i1 8nctx jar file Be sure to add the i18nctx jar file to the CLASSPATH when compiling application components that import Internationalization service classes 6 5 Beyond the example application This section provides information for advanced topics about the Internationalization service It includes information about gt Setting invocation locale and time zone gt Tracing the Internationalization service functions WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 6 5 1 Setting invocation locale and time zone The client may set the invocation locale and time zone using the set methods provided by the InvocationInternationalization interface In Example 6 7 locale en GB and simple time zone GMT transparently propagate on remote calls to server side components Server side application components such as a servlet JSP or EJB may use the Internationalization service to obtain the client locale and time zone Example 6 7 Setting the invocation context elements import com ibm websphere il8n context import java util private UserInternationalization il8nService
187. g oe corba server ejb2orbix ejb CreditInstitute jar BUILD SUCCESSFUL Total time 26 seconds This compilation doesn t have to be done because the generated classes are already packaged inside the EAR file It is only needed if the interface was changed Running the EJB client Before an order is placed Appl icationManager checks the customer s credit history The result is placed in the ViewBean object Figure 8 13 shows the result in case an exception is thrown 202 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Credit Check Information The customer is assumed to be approved Information confidential Figure 8 13 Results of creditability check The server shows the answer as well in its output com_ibm_itso_roch_credit_CreditInstituteImpl isCreditableFor called pers struct Person forename xy lastname pay 9 75 com_ibm_itso_roch_credit_CreditInstituteImp l isCreditableFor throwing exception InformationConfidential why Even the reason is confidential The following subsections explain what is happening when the creditability is checked gt Class overview gt Initializing the Java client ORB gt Getting the root context by resolving the stringified IOR gt Binding the CreditInstitute object Class overview The ApplicationManager class accesses the CreditInstituteWrapper class which hides the complexity of CORBA processing Example 8 17 sho
188. gnature and the second parameter is the object itself AddObject can be called multiple times until it contains all the parameters destined for the target method The order in which the objects are added to JMethodArgs must be the same as the order of parameters in the target method signature The Clear method in the JMethodArgs object removes all objects preparing it for re use Example 7 11 shows the situation where the equals method of a java lang String object is called This method has the signature public boolean equals Object anObject Therefore passing java lang String as a parameter would cause an error The stringb argument must be contained in a JMethodArgs object and labeled java lang Object Example 7 11 Passing a parameter to a method in an JMethodArgs object Dim StringClassProxy As Object Dim stringa As Object Dim stringb As Object Set StringClassProxy oXJB FindClass java lang String Set stringa Set stringb oXJB NewInstance StringClassProxy Bill oXJB NewInstance StringClassProxy Ted Dim args As Object Set args oXJB GetArgsContainer 138 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide args AddObject java lang Object stringb If stringa equals args Then End If Reuse the same argument container object args Clear Return values Although the signature of a Java method declares the return type the method may return a child or an implementor of th
189. h const CosNaming NamingContext NotFound amp context_as_obj default_context gt resolve_str demo_name_string Name is not yet bound create a new context CosNaming Name_var demo_name default_context gt to_name demo_name_string context_as_obj default_context gt bind_new_context demo_name Narrow the reference to a naming context CosNaming NamingContext_var demo_context CosNaming NamingContext _narrow context_as_obj if CORBA is_nil demo_context cout lt lt Error Cannot narrow naming context called lt lt demo_name_string lt lt lt lt endl throw CORBA BAD_PARAM return demo_context _retn CosNaming NamingContext_var demo_context create_demo_context default_context com ibm itso roch credit 0E NAMING DIR tmp_ref my_poa gt id_to_reference oid name default_context gt to_name com ibm itso roch credit CREDIT_NAMING_ ENTRY demo_context gt rebind name tmp_ref Putting the ORB into an active state The last step for starting up the server is to activate the POA manager and to instruct the ORB to listen for client requests This is shown in Example 8 15 Example 8 15 Letting the server listen for requests root_poa_manager gt activate cout lt lt Waiting for requests lt lt endl global_orb gt run Now the server is ready to handle requests 198 WebSphere Application Server Enterprise Edition 4 0
190. h in GSA ADP Schedule Contract with IBM Corp Contents CONTENTS aif ike es A ae ee a AN th ade eA inde ath tid ae ni AON hae eA ANA a iii Special notices sis ora erana ee eke eet Se aie er a eae ete vii IBM trademarks lt 2 5006 sa kg eee weak eitts we eae Pees he deh Sas me Eee viii Preface 4 34 24cf oka pe eee WER Se hed ee RI heed Re Rad eee Cee a ix The team that wrote this redbook 0 0 ccc ix Special Notices vesina araa wee i E beens Caer a Se beater ented ened Senedd xi Comments welcome s tereraa E EA ete teens xi Chapter 1 WebSphere Application Server Enterprise Edition overview 1 1 1 What is new in Version 4 0 0 0 0 6 aa 2 1 2 WebSphere Enterprise Services 0 cette 3 Chapter 2 Overview of the OrderEntry application 04 5 2 1 INtrOMUCTION iisi ee Ph a Ree Red ee ee et de ae ed ied be ea ee a 6 21 1 The ABC COMPANY 4c ch deve eek ce eee eek Gs ee ar eek oe ee cea te 6 2 1 2 The ABC Company database 0 tees 7 2 1 3 A customer transaction 0 0 0 eee 7 2 1 4 Application flow 0 0 ce teeta 7 2 2 OrderEntry application database layout 0 0 cece ee 10 221 Tables errai ari Bechet el dea eet a lie ele diated esol 10 2 3 Development environment 0 00 cee ee 14 Chapter 3 The Business Rule Beans service 2200000 eee 15 Bil OVONMWIOW aiaa a Bee AS Soe edd del add nnd over cea ee Aa Bh a a
191. he ORB try t printIn Initializing the ORB _orb CORBA 0RB_init intO NULL DSOM Getting the root context by bootstrapping The next step is to get the root context of the naming service Example 8 2 shows the method that handles this task First the initial reference of the NameService is resolved by bootstrapping and then narrowed to the NamingContext object Example 8 2 Getting root context by bootstrapping CORBA ORB_ptr MyOrb _orb std string MyOrb rootIOR Chapter 8 The CORBA services 171 CosNaming NamingContext_ptr MyOrb getRootContext CosNaming NamingContext_ptr rootContext NULL try t printIn Getting name server CORBA Object_var obj if _rootIOR t printIn By bootstrapping obj _orb gt resolve_initial_references NameService if CORBA is_nil obj err printin resolve_initial_references NameService returned nil nMake sure your server is running and you set SOMCBPROPS rootContext CosNaming NamingContext _narrow obj if CORBA is_nil rootContext err printIn name server narrowed to nil return rootContext Binding CustomerHome The connection to the CustomerHome is established through the CustomerFactory Itis a wrapper class that offers the methods of the CustomerHome and handles the possible remote exceptions The create and find methods of the CustomerFactory don t return Customer objects
192. he Submit button 7 This customer has qualified for the Gold level and receives a 7 discount Order Total 0 Discount 7 Total Order Discount 0 Implementing classified rules The Trigger Point framework provides a triggerSituational method This method first calls a classifier rule and then uses the derived classification to invoke a base rule The base rule in this case is called a classified rule it is classified by the string returned from the classifier rule The definition of the business rule is stated here 38 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Business rule definition Customers of different levels qualify for different specials To implement classified rules in WebSphere Studio Application Developer expand the OrderEntryWeb folder In the source rules folder you can find the implementation of three classified rules PreferredSpecials GoldSpecials and PlatinumSpecials These rule implementors return an array of specials java lang String that were passed to the rules as initialization parameters see Example 3 9 Example 3 9 Implementation of the Platinum Specials rule public void init Object parms String dependentRules String userDefinedData IRuleCopy rule throws BusinessRul eBeansException Save platinum level specials specials parms public Object fire TriggerPoint tp Object target IRuleCopy rule java lang Object parms throws BusinessRuleBeansEx
193. he actual business rules that need to be used is missing Follow these steps to import the business rules 1 Start OrderEntryServer in WebSphere Administrative Console Make sure there is no error in the Event Message pane of the Administrative Console 2 Open a command prompt 3 Run the following command 0E_HOME BRBeans ImportRules Note The assumption is that you have installed WebSphere Enterprise Services in the WAS_HOME Enterprise directory If this is not true you should edit the OE_HOME BRBeans ImportRules bat file Change the WAS HOME Enterprise line in the file to the directory name where you installed WebSphere Enterprise Services You should see no errors 5 To verify that the rules were imported run another command 0E_HOME BRBeans CheckRules Note The assumption is that you installed WebSphere Enterprise Services in the WAS_HOME Enterprise directory If this is not true you should edit the OE_HOME BRBeans CheckRules bat file Change the WAS_HOME Enterprise line in the file to the directory name where you installed WebSphere Enterprise Services The rule management application is started You should see the same folders as shown in Figure A 4 iolx File Edit View Help All Folders Rule Namespace H E CustomerRules H E DiscountRules OrderRules H E ShippingRules El com Figure A 4 Imported business rules 228 WebSphere Application Server Enterprise Edition
194. he directory structure When you unzip the OrderEntry ZIP file you should see a directory structure under OE_HOME There are two EAR files in the root directory gt OrderEntry ear Contains all the source and compiled code for the OrderEntry application OrderEntryWithoutBRBeans ear Is for those who want to go through the process of developing BRBeans The process is described in Chapter 3 The Business Rule Beans service on page 15 The OE_HOME directory also contains several subdirectories gt DB2 This directory contains the script files necessary to create the database used by the OrderEntry application ActiveX BRBeans and corba These directories contain files specific to a corresponding WebSphere Enterprise Service WebSphereWorkbench This directory contains several files that you can use in WebSphere Studio Application Developer This tool creates a special file called classpath for each project in the workspace The file contains the location of all projects folders and JAR files that are referenced by the current project refer to the WebSphere Studio Application Developer online help for the details on changing the class path If you plan to use WebSphere Studio Application Developer you can copy and paste the content of a file from the WebSphereWorkbench directory into a corresponding classpath file in WebSphere Studio Application Developer For example copy the content of OE_HOME WebSphereWorkbe
195. he method s return value Case sensitivity Java methods are case sensitive where ActiveX methods are not PowerBuilder doesn t support case sensitive method calls All calls are converted to lowercase at runtime This causes problems with the JClassFactory methods like FindClass Note There is a workaround way to solve the problem with PowerBuilder Refer to the following Web page http www7b boulder ibm com wsdd library samples powerbuilder html Visual Basic and VBScript also try to convert the case of some methods However the case of the method is also changed dynamically in the VB developer tool so the problem with method names can be identified before runtime If you type the following line of the code VB developer tool changes it myApp close 123 It is then changed to the following line when the cursor is moved to the next line myApp Close 123 The way to get around this problem in Visual Basic is to use the Cal1ByName function Cal 1ByName myApp close vbMethod 123 In VBScript a similar function called Eval does the same job Eval myApp close 123 Similarly Visual Basic may change the case of field references myApp create 123 Chapter 7 The ActiveX bridge service 137 This is converted to myApp Create 123 In Visual Basic the Cal1ByName function is used in the same way to reference the data fields that you would call a method Cal lByName myApp create vbLet 123 Here vbLet i
196. he queue connection factory can now be found through a JNDI lookup against WebSphere Application Server JMS Listener JMS Listener is installed with the JMS Enterprise Service Its functionality is to route messages arriving at a JMS destination to a message bean for processing as illustrated in Figure 4 14 JMS Listener is supplied as part of WebSphere Application Server Enterprise Edition It runs within WebSphere Application Server WebSphere Application Server A i gt JMS Listener gt Message Bean JMS destination Figure 4 14 JMS Listener routes messages to a message EJB The work of managing JMS Listeners is done by JMS Listener manager It provides the following services gt Creates a pool of dynamic session threads for use by JMS Listeners gt Creates and starts JMS Listeners based on the XML configuration file the XML configuration file is covered in 4 2 5 JMS Listener XML configuration file on page 65 gt Controls the cleanup of resources during server termination Chapter 4 Extended Messaging Service 63 Each JMS Listener completes several steps for the JMS destination that it is to monitor including gt Creating a JMS server session pool and allocating JMS server sessions and session threads for incoming messages gt Creating JMS connection consumers to listen for incoming messages gt If specified starting a transaction and requesting that it is
197. hers are implemented in Java as part of the WebSphere Administration Server JVM To have the ORB runtime completely initialized the AdminServer has to be started Note To install C SDK you have to select Custom install and make sure the C SDK box is selected The naming location and transaction services are implemented in Java The implementation repository is done as a C daemon regimpl exe It is located in the directory WAS_HOME Enterprise bin In the implementation repository you have to register your C server It stores basically a symbolic name for your server the name of the executable and the protocol it uses The SDK gives you the tools for the development processes described in the CORBA development on page 156 and in CORBA development for EJBs on page 158 The most important tools are gt idlc IDL compiler for C language mapping gt rmic Reverse IDL compiler for Java to IDL mapping gt Vtlib 1lib The CORBA valuetype library for C which covers many commonly used Java serializables in the java lang java io java util and javax ejb packages Note The C compiler linker and an archiver are not part of this SDK You also need a product like Microsoft Visual C 6 0 to have a complete development environment 162 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 8 3 C CORBA clients for the OrderEntry application In these scenarios we have written two differe
198. his business rule is another example of an internal business practice Variable information includes the total order amount and the discount rate gt Example 3 The capital gains tax rate is 28 percent for stock sold during 18 months from the date of purchase and 20 percent for stock sold after 18 months from the date of purchase This business rule is an example of an external government regulation Tax rate and time periods are the variable data From the BRBeans framework perspective all business rules belong in one of two categories gt Classification rules gt Base rules Classification rules return a classification based on factors involved in a business process The BRBeans framework requires classification rules to return an object type of java lang String A classification rule is demonstrated in Example 1 The rule implementor must return a string that represents a customer classification Preferred Gold based on the customer s YTD purchases The rest of the business rules fall into the base rules category In the BRBeans framework base rules return an array of java lang Objects Implementations of business rules in Example 2 and Example 3 above must return an array with one object of type java lang Float or java lang Integer Note Primitives must be passed as java lang Object using primitive wrapper classes 3 2 Implementing business rules with the BRBeans framework This chapter shows how to implement one business r
199. hods za oQ0c In the Navigator view of WebSphere Studio Application Developer expand the OrderEntryWeb source rules folder Double click CustomerClassification and implement the methods that are explained here init The init method expects three parameters e The amount of YTD purchases for the Preferred level e The amount of YTD purchases for the Gold level e The amount of YTD purchases for the Platinum level 26 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide These initialization parameters are specified in the Rule Management Application They are passed as an array of java lang 0bjects Object parms and used by the fire method to determine customer classification Example 3 2 shows the init method implementation Example 3 2 Implementation of the init method public void init Object parms String dependentRules String userDefinedData IRuleCopy rule throws BusinessRuleBeansException Three parameters are expected ImplementorHelper assertParamLength parms 3 CustomerClassification init Store the initialization parameters preferredLevel Integer parms 0 intValue goldLevel Integer parms 1 intValue platinumLevel Integer parms 2 intValue initialized true fire This method expects one parameter the amount of YTD purchases The amount of YTD purchases is compared to the level amounts and the resulting classification is returned as j
200. hreads for each JMS Listener In some cases it will be necessary to configure multiple application servers each with a set of listeners on a given machine or node This relaxes the constraint of 20 threads in a Server Session Thread Pool and in fact multiplies it by the number of servers defined for a given node Continuing to add servers until maximum resource utilization of the machine is achieved ensures maximum efficiency of the JMS Listener service It is possible that at some point adding additional servers no longer increases throughput 4 4 3 Exception handling Exception handling for a message bean is unique due to asynchronous processing of the message A failure cannot be reported to a client program Exceptions should not be returned from the onMessage method but if this occurs they must be handled by the container Any exception returned from the onMessage method causes the message to remain on the JMS destination JMS Listener retries If the situation that caused the exception still exists the message remains on the destination Therefore JMS Listener will be able to read the message again from the destination This action may not be desirable The maximum number of times that JMS Listener reads the message from the queue is configured via the MaxRetries attribute of the XML configuration file When the maximum number of reads has occurred the JMS Listener for that specific destination is stopped Once the problem is re
201. hs 1ibPaths WAS HOME java jre lib ext set libPaths 1ibPaths WAS HOME 1ib set 1ibPaths 1ibPaths MQSeriesHome java lib java Djava ext dirs libpaths DMQJMS_LOG_DIR MQ_JAVA_INSTALL_PATH 1log DMQUMS_TRACE_DIR MQ_JAVA_INSTALL_PATH trace DMQJMS_INSTALL_PATH MQ_JAVA_INSTALL_PATH com ibm mq jms admin JMSAdmin 1 2 3 4 5 The JMSAdmin tool is invoked at the command line by entering the jmsadmin command at a command prompt within the lt MQSeries install directory gt Java bin directory In doing so the tool places you at the root context for JMS called InitCtx as shown in Figure 4 7 Chapter 4 Extended Messaging Service 57 Ei C IBM MQSeries Java bin jmsadmin 648 C66 lt c gt Copyright IBM Corp 1999 All Rights Reserved tarting MQSeries classes for JavaCtm gt Message Service Administration InitCtx gt m X Figure 4 7 JMSAdmin places you at the root context when it launches Note You can find details of JMS resources defined and administered by the JMSAdmin tool in Section 4 6 3 4 Support for the use of MQSeries Java Message Service resources on the Web at http www ibm com software webservers appserv doc v40 aee index html JNDI context definitions We chose OrderEntry JMS as the top level context for our JMS resources Each of the resources in Figure 4 6 are defined using the following administration commands Def ctx OrderEntry chg ctx OrderEntry Def ctx JMS
202. ib user32 1ib set LIB_FLAGS nologo cd 0E_HOME corba tools nmake nologo f makefile tools Compiling the Trace class cl 1 0E_HOME corba client ibm2ejb 1 0E_HOME corba tools 1 WAS_HOME Enterprise include I include GX c nologo MD Od DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE DUSE_JAVA_EX DORB WebSphere Trace cpp Trace cpp Compiling the Error class cl 1 0E_HOME corba client ibm2ejb 1 0E_HOME corba tools 1 WAS_HOME Enterprise include I include GX c nologo MD Od DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE DUSE_JAVA_EX DORB WebSphere Error cpp Error cpp Compiling the Warning class cl 1 0E_HOME corba client ibm2ejb 1 0E_HOME corba tools I WAS_HOME Enterprise include I include GX c nologo MD Od DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE DUSE_JAVA_EX DORB WebSphere Warning cpp Warning cpp Compiling the MyOrb class cl 1 0E_HOME corba client ibm2ejb 1 0E_HOME corba tools 1 WAS_HOME Enterprise include I include GX c nologo MD Od DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE DUSE_JAVA_EX DORB WebSphere MyOrb cpp MyOrb cpp Compiling the CustomerWrapper class cl 1 0E_HOME corba client ibm2ejb 1 0E_HOME corba tools 1 WAS_HOME Enterprise include I include GX c nologo MD Od DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE DUSE_JAVA_EX DORB WebSphere CustomerWrapper cpp CustomerWrapper cpp Compiling the CustomerFactory class cl IF Henning oe corba
203. ibute of MyClass return a java lang String object This is automatically converted to a Visual Basic String 7 5 3 Accessing Java objects The New nstance method of the XJB JClassFactory object is called to create a new instance of a class The method takes the JClassProxy object as a parameter and returns JObjectProxy which is used to access the methods and fields of the new instance The bridge is responsible for maintaining a hash table that associates the JObjectProxy object with the original Java object Example 7 9 shows how to call the no parameter constructor of MyClass 136 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Example 7 9 Instantiating myObject via the no parameter constructor Dim myObjectProxy As Object Set myObejctProxy oXJB NewInstance myClassProxy To call a constructor with parameters the arguments are listed after JClassProxy in the call to NewlInstance see Example 7 10 Example 7 10 Instantiating myObject via a constructor that takes java lang String as a parameter Dim myObjectProxy As Object Set myObjectProxy oXJB NewInstance myClassProxy StringParameter This time the Visual Basic String object StringParameter is automatically converted to an instance of java lang String 7 5 4 Invoking Java methods There are several issues you need to deal with while calling Java methods gt Case sensitivity gt Passing Object type parameters gt Processing t
204. ication Server Enterprise Edition 4 0 A Programmer s Guide The CORBA services This chapter discusses gt Positioning of CORBA CORBA in general Role of CORBA in J2EE gt Overview of WebSphere Application Server CORBA support WebSphere support scenarios Interoperability with EJB C CORBA Software Development Kit SDK gt C CORBA clients for the OrderEntry application Configuring the environment IBM client of the Customer EJB VisiBroker client of the Customer EJB Problem determination gt Connecting the OrderEntry application to a C CORBA server Configuring the environment Connecting to an Orbix server Problem determination Note To understand the structure of the OrderEntry application and to run it read the instructions in Appendix A Downloading and installing the OrderEntry application on page 221 Copyright IBM Corp 2002 153 8 1 Positioning of CORBA CORBA is the acronym for Common Object Request Broker Architecture as specified by the Object Management Group It was adopted to provide a language and vendor neutral standard for object distribution It hides location and network complexities from the programmer and provides services such as naming transaction and security The CORBA architecture is built around a special layer the Object Request Broker ORB that facilitates communication between clients and server objects A client ORB ma
205. iles File name Description OE zip All sample code in the ZIP format System requirements for downloading the Web material The following system configuration is recommended Hard disk space 2 GB minimum Operating System Windows NT 2000 Processor 450 MHz or higher Memory 512 MB Copyright IBM Corp 2002 231 How to use the Web material Refer to Appendix A Downloading and installing the OrderEntry application on page 221 for installation instructions 232 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Related publications The publications listed in this section are considered particularly suitable for a more detailed discussion of the topics covered in this redbook IBM Redbooks For information on ordering these publications see How to get IBM Redbooks on page 234 gt gt WebSphere Version 4 Application Development Handbook SG24 6134 Design and Implement Servlets JSPs and EJBs for IBM WebSphere Application Server SG24 5754 Other resources MQSeries Using Java SC34 5456 is also relevant as a further information source Referenced Web sites These Web sites are also relevant as further information sources gt Copyright IBM Corp WebSphere Studio Application Developer http www ibm com software ad studioappdev IBM WebSphere InfoCenter http www ibm com software webservers appserv doc v40 aee index html MQSeries classes for Java and MQSeri
206. iller phone 01234 56789 The output of the executable would be like the following example TRACE Entering main TRACE Reading program arguments TRACE Program values TRACE forename joe id 1234 lastname miller method create phone 01234 56789 TRACE Initializing the ORB TRACE By bootstrapping TRACE Getting name server TRACE Constructing name entry TRACE Resolving name entry domain legacyRoot CustomerGlobal Chapter 8 The CORBA services 169 TRACE Narrowing CustomerHome TRACE Creating a CustomerBean with the following parameters TRACE CustomerID 1234 TRACE ForeName joe TRACE LastName miller TRACE Phone 01234 56789 TRACE Customer created TRACE 1234 joe miller 01234 56789 Important At the time this redbook was written a call failed to the findByPrimaryKey method with the key class that wraps java lang String The problem was reported to the WebSphere development team However this problem needs more clarification EJB specification v1 1 recommends using the EJB s primary key field as the primary key class when a primary key class maps to a single field Following this recommendation we would need to use java lang String customer ID filed in the findByPrimaryKey method WebSphere Application Server works fine with String The following subsections explain what happens when ibm2ejb exe is executed Class overview Initializing the IBM ORB Getting the r
207. in turn are the building blocks for transaction processes and compensation pairs you can find more on this in Process on page 213 To support the highest level of reusability all BPBeans components define their external interface in a declarative manner through the component s properties This declaration describes the interfaces of the components together with requirements on the environment in which the component may be used The components are connected to each other using messages A component is given work via input messages and can generate work for other components via output messages However a given component does not know who gave it the work or to whom its messages will be given Such association between components is called a loosely coupled connection Chapter 9 The Business Process Beans service 211 As a result a component has almost no dependency on any other component and can be built separately from the rest of the application Also a BPBeans component can be assembled with any other BPBeans component that satisfy its external interface as described in Activity on page 212 However this reusability comes with a cost in the designing phase All external interfaces for the BPBeans components have to be carefully designed 9 2 BPBeans programming model 9 2 1 Task The BPBeans programming model is based on the variety of the BPBeans components A BPBeans component is a JavaBean class that follows the ru
208. ination JNDI context queue connection factory are defined and givena JNDI entries to enable lookup JMS Listener message beans All JMS resources JNDI path have a corresponding JNDI entry in WebSphere JMS Provider JMS Listener is provides physical configured from an queues XML file JMS Provider MQ XML Configuration File Physical queues JMS Listener configuration Figure 4 4 The core components of JMS in the point to point model The four components are split between WebSphere Application Server Enterprise Edition and IBM MQSeries JMS Provider This defines a natural approach in the JMS Listener configuration process which we explore in the following sections gt On the JMS Provider side Provide physical queues Define JMS resources and assign them a JNDI path to enable them to be found via JNDI lookup The JMSAdmin tool is supplied by MQSeries The following three steps need to be performed 54 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide i Create JNDI context the context definitions within which the JMS resources reside ii Bind JNDI names to the physical queues other queues beside JMS destination may be used by the message bean to send information to other systems iii Specify the queue connection factory the Java interface that is used to create a connection from the Java application to the JMS destination gt On the WebSphere Application Server Enterprise
209. ince a JMS subscriber only receives publications that have its correlation identifier and these are unique a given publication message must be delivered to its defined subscriber This means subscription queues should not be cluster queues when the hosting queue manager is part of a cluster 88 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 4 5 The future of WebSphere messaging WebSphere Application Server Enterprise Edition Version 4 0 combines the basic JMS and JMS XA support of WebSphere Advanced Edition 4 0 with support for JMS Listeners and message beans This is sufficient to begin deploying applications that integrate legacy systems via messaging and new systems that are coupled by asynchronous means The next release of WebSphere Application Server Enterprise Edition will implement J2EE 1 3 and EJB 2 0 specifications This will include a certified support for message driven beans This message driven bean implementation will be an evolution of what is available in WebSphere Application Server Enterprise Edition now Modifications to the EJB container to ensure compliance with EJB 2 0 message driven beans is underway now Tooling for creation and deployment is being modified to leverage the Message Driven Bean deployment descriptor format Chapter 4 Extended Messaging Service 89 90 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The WorkArea service WorkArea provides a s
210. ing output x Generating the Customer client stub idlc J Djava ext dirs WAS HOME 1ib WAS_HOME Enterprise lib I d com ibm itso roch wasaejb mcpponly md1lname Customer shh uc com ibm itso roch wasaejb Customer id Generating the CustomerKey client stub idlc J Djava ext dirs WAS HOME 1ib WAS_HOME Enterprise lib I d com ibm itso roch wasaejb mcpponly md1lname Customer shh uc com ibm itso roch wasaejb CustomerKey id x Generating the CustomerHome client stub 166 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide idic J Djava ext dirs WAS HOME lib WAS HOME Enterprise lib I d com ibm itso roch wasaejb mcpponly md1lname Customer shh uc com ibm itso roch wasaejb CustomerHome id Compiling and linking the stubs The stub files have to be compiled They could have been directly linked to the main executable but we decided to put them together in a DLL Note that the name of the library already is provided in the previous step to the IDL compiler as parameter md11name Customer makefile ibm2ejb executes the following steps 1 Compile the stubs to object files The output is x Generating the Customer object cl 1 0E_HOME corba tools I I WAS_HOME Enterprise include I include DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE GX c nologo MD Od DSOM DLL_Customer com ibm itso roch wasaejb Customer_C cpp Customer_C cpp Generating the Custome
211. ing why exception InformationConfidential string why interface CreditInstitute boolean isCreditableFor in Person pers in double pay raises PersonNotFound InformationConfidential 3 credit roch itso ibm com The nested module structure is mapped to the package name There are three constants that define the name of the root IOR file and the entry in the naming service The constants will be used from the clients and the server Building the server To build the server you simply have to run a makefile by executing the following two commands cd 0E_HOME corba server ejb2orbix nmake f makefile ejb2orbix server This file executes all the steps that are described in the following subsections 1 Generate the server sources 2 Modify the generated server sources 3 Compile the server code We show the output of the commands that are executed by the makefile You don t have to execute any of the commands manually But you could do so if you are interested in building the client manually step by step The nmake may execute the commands in a different order because it doesn t follow a sequence of commands but resolve dependencies The nmake command is described in detail in the online documentation of Microsoft Visual C The build of the server takes place in the subdirectory srv To delete all the generated files and directories you call the two commands cd 0E
212. inking the vb2ejb exe executable link DEBUG NOLOGO INCREMENTAL NO LIBPATH 0E_HOME corba client vb2ejb LIBPATH 0E_HOME corba tools LIBPATH VBRODERDIR lib vb2ejb obj ProgVals obj Customer 1ib 0E_HOME corba tools tools lib SUBSYSTEM CONSOLE OUT vb2ejb exe Creating library vb2ejb lib and object vb2ejb exp The output of the whole process is the executable vb2ejb exe file Building the IOR tool The IBM client uses a technique called bootstrapping This allows this client to get the root context of the naming service For the VisiBroker client this does not work Therefore we create a small tool that writes the string version of the root naming context s reference to a file This file is then read by the client to connect to the naming service The makefile vb2ejb file creates the IOR tool and produces the following output Creating the tool to get the naming root IOR WAS_HOME java bin javac com ibm itso roch wasaejb NamingClient java Running the client Before you can start the client you have to create the file that stores the IOR of the root naming context This is done by calling the following two commands cd 0E_HOME corba vb2ejb create_root_ior_file bat After that you can call vo2ejb exe The general usage of the executable is vb2ejb method lt method gt id lt id gt forename lt fname gt lastname lt Iname gt phone lt phone gt The following methods are available create id lt id gt
213. inventory update notification from an external stock control system We select the point to point JMS messaging model To add this functionality we need to configure the JMS Listener service and develop a message bean We call it the StockDel iveryUpdate message bean This bean performs the following steps 1 Perform a JNDI lookup of the Stock entity bean representing the stock level 2 Update the inventory level for a given item at a given warehouse by a given quantity The information to the StockDeliveryUpdate message bean is delivered as a comma separated list of values within the body of a JMS message Finally confirmation of the message process is placed on an output queue This is illustrated in Figure 4 3 Chapter 4 Extended Messaging Service 53 WebSphere Application Server StockDeliveryUpdate z gt JMS Listener gt message bean gt Q Qin l Qout Stock Entity Bean Figure 4 3 JMS point to point as applied to the OrderEntry application The four main components of the JMS Listener service are configured before we can deploy the message bean Let s discuss this configuration 4 2 1 The core components of JMS point to point Several core components enable the JMS Listener service for Java applications within WebSphere Application Server We have to configure each component shown in Figure 4 4 JMSAdmin WebSphere Application Server JMS resource definitions dest
214. ion about caching see Caching on page 46 30 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Example 3 4 Implementation of the getCustomerLevel method public void getCustomerLevel int amountYTD throws Exception Create new trigger point TriggerPoint tp new TriggerPoint Disable caching for demonstration purpose tp disableCaching The rule expects one parameter the amount of YTD purchases to the rule Object firingParams new Integer amountYTD String ruleName CustomerRules CustomerClassification Call the rule Object result tp triggerClassifier null Target Object not reqiured by rule implementation firingParams Rule Implementor firing parameters ruleName The name of the rule to fire if result null itemsViewBean setApplicationError The rule returned null else Rule successfully called Object resultArray Object result The rule returns one String customer level customerLevel String resultArray 0 Save customer level itemsViewBean setCustomerLevel customerLeve d Save the changes to the ApplicationMgr class 6 Save all opened files and export the OrderEntry EAR project from WebSphere Studio Application Developer to OE_HOME 7 Name the file OrderEntryWithRules ear 8 Install OrderEntryWithRules ear in WebSphere Application Server Enterprise Edition Attention Prior to installing O
215. it the Internationalization Service properties a On the Custom tab click Edit The Edit Custom Service dialog is displayed b Click the General tab c In the Classname field verify or change the following entry see Figure 6 2 com ibm ws il8n context ServiceInit d Select the Enabled check box if not already selected e Click OK The Edit Custom Service dialog closes f Click Apply Your changes are saved Chapter 6 The Internationalization service 115 Fa Edit Custom ServiceInternationalization Service Custom Name internationalization Service Description Classpath al Classname lcorn ibrn ws i1 8n context Servicelnit Configuration file URL V Enabled OK Cancel Help Figure 6 2 Edit Custom Service dialog These settings cause the Internationalization service to initialize when starting or restarting the corresponding application server 6 4 2 Enabling internationalization context within EJB Java application clients To enable the Internationalization service for EJB Java application clients the i18nctx jar file must appear in the CLASSPATH constructed by the launchClient utility When invoking a client application launchClient correctly configures the CLASSPATH to include the i18nctx jar file Then it initializes the service for use within that application See the WebSphere InfoCenter documentation Launching Java application clients in the J2EE application client container for more in
216. ity calls to the WorkArea methods locate the WorkArea associated with the current thread Notice that we do not call the begin method here that is done from the doPost method as described in the next section The lookup binds to the facility that maintains WorkAreas The begin method creates a new or nested WorkArea associated with the current thread A reference to the WorkArea facility can work for different threads but calls to the service method of a servlet and calls to an EJB can come from different threads We must only call the begin and complete methods within the scope of a single thread 5 2 2 Creating and populating WorkArea We create and populate WorkArea in the doPost method of the OrderEntryServlet by invoking the createWorkArea method All the information needed in other parts of the application is stored in WorkArea Invoke the begin method to create a new WorkArea and associate it with the current thread The begin method takes a String argument that is used as the name of WorkArea This name is used primarily for debugging In this case we used the servlet name to identify the servlet that created WorkArea The only requirement for the name of WorkArea is that it is not null To set the properties we use the set method and specify the name and value of the property Example 5 2 shows the method that creates WorkArea and sets the values Example 5 2 Creating and populating WorkArea import com ibm websphere workarea pr
217. ivate UserWorkArea workArea private void createWorkArea HttpServletRequest request Create a new WorkArea associated with this thread workArea begin OrderEntryServlet try Get the customer information from the request String id request getParameter customerID String lastName request getParameter lastName String firstName request getParameter firstName Store the customer information in WorkArea workArea set customerID id workArea set lastName lastName workArea set firstName firstName Get the item information from the request String itemID request getParameter itemID 94 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide String quantity request getParameter quantity Store the item information in WorkArea workArea set itemID itemID workArea set quantity quantity Since we did not specify read only properties this exception will not occur here If this exception were caught it would indicate a coding error catch PropertyReadOnly e e printStackTrace WorkArea was created inside this method neither of these exceptions will occur NoWorkArea would indicate WorkArea was not created catch NoWorkArea e e printStackTrace NotOriginator would indicate WorkArea was created by some other servlet or bean catch NotOriginator e e printStackTrace Now the information from the request is
218. izable interface for more details on making objects serializable 5 3 6 CORBA considerations Although the WorkArea facility can be used across Enterprise JavaBeans and the CORBA programming models many composed data types cannot be successfully used across those boundaries For example if a SimpleSampleCompany instance is passed from the WebSphere environment into a CORBA environment the CORBA application can retrieve the SimpleSamp1eCompany object encapsulated within a CORBA s any object from WorkArea but it cannot extract the value from it Likewise an IDL defined struct within a CORBA application and set into WorkArea is not readable by an application using the UserWorkArea class Applications can avoid this incompatibility by directly setting only primitive types such as integers and strings as values in WorkAreas or by implementing complex values with structures designed to be compatible like CORBA valuetypes Also CORBA Anys that contain either the tk_nul1 or tk_void typecode can be set into WorkArea by using the CORBA interface but the WorkArea specification cannot allow the J2EE implementation to return null on a lookup that retrieves these CORBA set properties without incorrectly implying that there is no value set for the corresponding key If a J2EE application tries to retrieve CORBA set properties that are non serializable or contain CORBA nulls or void references the com ibm websphere workarea IncompatibleValue exception i
219. ject resultArray Object result Multiple discount rules might have been found for int i 0 i lt resultArray length i Integer discountValue Integer resultArray i orderDiscount orderDiscount discountValue intValue jtemsViewBean setOrderDiscount orderDiscount The default finding strategy DefaultNonClassifierFindingStrategy returns all non classifier rules that match the DiscountRules CalculateDiscount name we configured two rules with this name The default filtering strategy is Accept Any all of the rules that are found stay eligible for firing The default combining strategy is Return All the results of all rules fired by the BRBeans framework are returned two rules in this example Chapter 3 The Business Rule Beans service 35 Testing the application To see the results of the rule implementation test the application 1 2 Export and install the OrderEntry application if necessary In the WebSphere Administrative Console start OrderEntryServer if it is not already started Bring up the application home page http localhost lt port_number gt OrderEntry index htm Select New Order 5 Type the customer ID 0002 and click the Submit button You can see the discount value based on customer level see Figure 3 11 6 Add several items Item ID 000017 quantity 1 Item ID 000013 quantity 1 Item ID 000002 quantity 1 7 As you add the items you
220. kArea that the methods operate on is the one associated with the current thread 2 Call the begin method This method creates WorkArea If WorkArea is already associated with the current thread a nested WorkArea is created inside of it This step is not necessary if we only want to read the properties in an existing WorkArea and not change them 3 Use the set and get methods to access and change properties in WorkArea 4 Call the complete method This method terminates the current WorkArea This must only be done in the same servlet or bean that called the begin method 5 2 1 Binding to the WorkArea facility First we bind to the WorkArea facility using JNDI To do this we need to access an initial context object Example 5 1 shows binding to the facility in the init method of OrderEntryServlet Example 5 1 Binding to the WorkArea facility import com ibm websphere workarea import javax naming private UserWorkArea workArea public void init ServletConfig config throws ServletException super init config SuperServlet SYSTEM InitialContext jndi null Bind to WorkArea facility try Chapter 5 The WorkArea service 93 jndi new InitialContext workArea UserWorkArea jndi lookup java comp websphere UserWorkArea This exception indicates a problem binding to the service catch NamingException e e printStackTrace flexLog OrderEntryServlet init Once we bind to the facil
221. l discountParams ruleName resultArray Object result Multiple discount rules might have been found for int i 0 i lt resultArray length i Integer discountValue Integer resultArrayLi discount discount discountValue intValue Get the total of with the discount orderTotal orderAmount orderAmount discount 100 Add tax orderTotal orderTotal orderTotal taxRate 100 The second rule is the shipping rate rule ruleName dependentRules 1 Get the shipping rate Chapter 3 The Business Rule Beans service 43 result tp trigger null shippingParams ruleName resultArray Object result shippingCharge Float resultArray 0 Add shipping charge orderTotal orderTotal shippingCharge floatValue return new Float orderTotal Rule configuration Start the Rule Management Application if it is not already started see 3 2 1 Setting up the development environment on page 19 Expand the Rule Namespace folder and click the OrderRules folder Open the Properties window for the CalculateOrderTotal rule On the General tab the rule is classified as a base rule Click to the Dependent rules tab The order in which the rules are listed is important because the fire method expects the rules to be ina specified order see Figure 3 18 _ Rule Properties OrderRules CalculateOrderT DiscountRules CalculateDiscount ShippingRules CalculateShippingCharge Add
222. launchClientXJB bat file in turn calls setupCmdLineXJB bat to set up the environment variables But unlike the standard launchClient command it does not subsequently start the ActiveX application inside a client container Instead it simply executes the application as is The additional environment variables and addition of the J2EE Application Client JRE to the PATH enables the ActiveX application to subsequently initialize a JVM within its own process and subsequently launch a client container within that JVM The code that starts the J2EE client container is in the X BGetJ2EEClientContainer method in the ActiveX_XJBHelpers module Example 7 4 After the JVM is initialized a com ibm websphere client applicationclient aunchClient object is instantiated and the launch method is invoked passing in string parameters gt Bootstrap host gt Bootstrap port Chapter 7 The ActiveX bridge service 131 gt Client JAR filename if there is more than one in the EAR file otherwise it is set to an empty string gt initonly set to true to stop the container calling the Main class see 7 8 1 Setting up the Main class on page 148 gt EAR file name gt EAR file extract directory gt Debug trace parameters Example 7 4 The code in ActiveX_XJBHelpers that launches the client container Public Function XJBGetJ2EEClientContainer oXJB As Object strEARFile As String _ strBootstrapHost As String strBootstrapPort As String _
223. le je getLinkedException if le null System out printIn linked exception le catch Exception e System out printIn failed with e finally oQueueConnection close 8 Generate the bean s deployed code Right click the bean in the J2EE view and choose Generate Deploy Code see Figure 4 19 Chapter 4 Extended Messaging Service 73 G E EJB Modules Syster OrderEntry EJBs Racal E amp Customer Syster H District H tem Syster E amp Order putMe H OrderEntryClerk Syster H OrderPlacement H Stock amp Samia eels System oui New da AssemblyDescript E Server Configurations Bs Run on Server 4 a Server Instances El c9 Databases Generate Deploy Code Quick Links private Conte ResourceB String JNI String JNI String JNI Delete Propertie oPropertis oPropertic InitialCor return oI Navigator J2EE View private int u s 5 a Outline 1 F o Oo X i Get the import declarations ESR El StockDeliveryUpdateBean mo muGaccinnAy iavav aih CaccinnCantavt 87 Tasks R items Figure 4 19 Generating EJB deployed code 9 Right click OrderEntry EJBs in the J2EE view and select Open With gt EJB Editor 10 Click the References tab 11 Under StockDeliveryUpdate add an EJB reference to the Stock entity bean and save the file 12 The
224. les of the BPBeans framework and can be plugged into this framework Some components are included as part of the framework others need to be created by a Java developer Each component has a set of well defined responsibilities in the BPBeans application We discuss the following components gt Task Activity Process gt Resource Context gt Outcome Decider v Note For more information about the BPBeans components refer to Business Process Beans Programming Guide which is part of the online documentation A piece of work in the BPBeans model that performs some business function is called a task A task receives and sends messages through objects called input and output ports There are two types of tasks in the BPBeans model gt Activity The simplest task that implements a piece of business logic gt Process A task that manages a collection of other tasks activities or other processes Activity An activity is a BPBeans component that represent a basic task in the BPBeans model the smallest piece of business logic An activity has to be created by a Java developer It must produce a result called an outcome in the BPBeans framework All possible outcomes for a given activity are grouped in the object called outcome set Depending on the logic of an activity the outcome can be of different types boolean or integer A JavaBean class has to implement the com ibm bpbbeans Activity interface to be treated
225. lient ORB The constructor of the CreditInstituteWrapper reads the name of the file that stores the server IOR see Example 8 13 on page 197 from the OrderResourceBundle properties file and passes it to the ClientOrb constructor The initialization of the Java client ORB is similar to the ones for the C clients shown in Initializing the IBM ORB on page 171 and Initializing the VisiBroker ORB on page 183 Example 8 18 shows the listing of the CreditInstituteWrapper class constructor Example 8 18 Initializing the Java client ORB public CreditInstituteWrapper ResourceBundle resources ResourceBundle getBund e OrderResourceBundle String iorFile resources getString nameservice ior directory iorFile System getProperty file separator jiorFile ROOT_IOR_FILENAME value String nameEntry OE_NAMING DIR value CREDIT_NAMING ENTRY value org omg CORBA Object instObj null ClientOrb orb new ClientOrb iorFile ij public class ClientOrb onl vate ORB orb null public ClientOrb String filename Properties orbProps new Properties orbProps put org omg CORBA ORBClass com ibm CORBA iiop ORB 204 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide this orb ORB init String null orbProps In addition the string version of the naming services root IOR has to be read from the file This process is shown in Example 8 19 Example 8 19 Reading the
226. locale that specifies a language code but no country code Server application components accessed from a client browser may need to use means other than the Internationalization service to determine the correct country code for the client This could be accomplished by asking the HTTP client to specify their country if the country code was not received with the locale Chapter 6 The Internationalization service 113 6 3 3 Retrieving and using the invocation internationalization context Example 6 6 shows a method that retrieves the time and formats it according to the invocation internationalization context Note that in the example application the invoking component requests are made to a servlet from an HTTP browser client so the invocation and caller time zone are actually the JVM time zone of the server Example 6 6 Retrieving and using the invocation internationalization context import com ibm websphere il8n context import java util private InvocationInternationalization invI18N public String getTime TimeZone timeZone Locale locale Get the time from the invocation timeZone invI18N getTimeZone Get the locale for formatting from the invocation locale invI18N getLocale Get the current date and time for the specified time zone GregorianCalendar cal new GregorianCalendar timeZone locale Date date cal getTime Format the date and time for the locale DateFormat df DateFormat ge
227. lorer and the Administration Console of WebSphere Application Server along with the expected results Plus it introduces and explains the publish subscribe messaging model Note To understand the structure of the OrderEntry application and to run it read the instructions in Appendix A Downloading and installing the OrderEntry application on page 221 Copyright IBM Corp 2002 51 4 1 An overview of basic JMS and JMS Listener Basic JMS support allows Java applications to communicate asynchronously using JMS APIs Communicating applications do not need to run at the same time or have any awareness of each other they are loosely coupled JMS is a service oriented API specification That is the JMS API prescribes messaging functionality in terms of interfaces which JMS vendors then implement Programmers work with JMS through these interfaces Although the JMS specification is still new it has been implemented by several vendors including IBM and has been endorsed by many others One example of JMS could be a retail company taking orders for products over the Internet and using JMS to communicate with a supplier to re order stock as items are sold When the stock arrives a separate warehousing company can use JMS to update the recorded stock level of the retail company There is though a shortcoming with the basic JMS support an application has to implement some mechanism for polling for the messages on the incoming que
228. lt Application Server is running b Start the Rule Management Application if it is not already started see 3 2 1 Setting up the development environment on page 19 c In the Rule Management Application expand the Rule Namespace folder and select the CustomerRules folder The Rule Management Application should look like the example shown in Figure 3 6 Rule Browser a E loj xj File Edit View Help All Folders Rules in folder CustomerRules Rule Namespace Name a Status Start Date H O EEE Specials in effect 171 01 12 01 AM af H E DiscountRules 9 Specials in effect 1 1 01 12 00 AM H E OrderRules 9 Specials in effect 141 01 12 00 AM H 6 ShippingRules 3 H E com P E mi 3 Rules Figure 3 6 Configuring the CustomerClassification rule in the Rule Management Application d Right click the CustomerRules folder e Select New gt Rule f On the General tab complete the required fields and actions see Figure 3 7 i For Name enter CustomerClassi fication ii For Start Date enter 01 01 01 12 01 AM iii Select the Rule performs a classification radio button 28 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide o x Rule Properties CustomerRules CustomerClassification mplementation Description Dependent Rules Other rName and location Folder name jCustomerRules Name MjCustomerClassification Period when rule is in effect Start da
229. lues Dim CalendarClassProxy As Object Dim oCalendar As Object Dim oDate As Object Dim time As Long Set CalendarClassProxy oXJB FindClass java util Calendar Set oCalendar CalendarClassProxy getInstance Set oDate oCalendar getTime time oDate getTime Chapter 7 The ActiveX bridge service 139 7 5 5 Handling arrays Handling arrays in automation containers is similar to handling arrays in Java When Java arrays are passed to ActiveX their elements are converted to JObjectProxy objects or according to the Data Conversion Table if they correspond to COM primitives The array is then wrapped in a variant array before being passed to the automation container For this reason the result of a call to a Java object that returns an array must be assigned to a variant or a variant array The use of variants with arrays is needed so the same bridge can be used to support both Visual Basic and VBScript The retuned variant can t be interrogated to discover the data type However since the bridge can determine the actual data type enclosed in the variant wrapper the array can be passed as a parameter to other Java method calls Methods calls on the variant element will also invoke the appropriate method on the Java object Example 7 13 shows the GetAl Customer method in the COrderClerk module of the Visual Basic Order Entry Client Clerk is the variable that references the OrderEnrtyClerk session EJB Clerk findAl Customers elements
230. m the Qin JMS destination As a message is passed to the StockDeliveryUpdate bean it accesses the Stock entity bean to increase the inventory quantity for a particular product at a particular warehouse Note The message bean uses the Java classes supplied by MQSeries The MQ classes for Java are available from the MQSeries Web site as a support pack http www ibm com software ts mqseries txppacs ma88 html The bean is developed using WebSphere Studio Application Developer see Figure 4 18 1 Use the EJB creation wizard The code produced by the wizard is compatible with the requirements stated above The bean creation dialogue is invoked by expanding the EJB Modules tree 2 Right click OrderEntry EJBs in the J2EE view 3 Select New gt Enterprise Bean WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Lay APPIA VIGN rouse E Web Modules C EJB Modules Create EJB E eset amp OrderEningEJBs Create an Enterprise Bean G Customer TS District Generate code for EJB amp tem amp Order P StockDeiveryUpdste SSS OrderEntryClerk Bean name StockDeliveryUpdate OrderPlacement EJB project Deployed_OrderEntryEJB gt amp Stock da AssemblyDescriptor Bean type Session bean gt Server Configurations a koo o X a Server Instances SaN SUD SEEDS fect GY Databases Default package root ejbModule Browse Bean class StockDeliveryUpdateBean
231. mponents to the easily modifiable model files stored in XMI format gt Providing a non programmatic way of changing the application behavior by modifying the BPBeans properties gt Providing a server environment for testing of an application model To put it another way the BPBeans components and the server in which they reside represent a workflow system A typical application built upon the BPBeans framework looks like the diagram shown in Figure 9 1 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Applications Business Services amp Extended Transactions Compensation Pairs Transactions Activities amp Resources Data amp Existing Systems Enterprise JavaBeans Figure 9 1 Typical application built with BPBeans technology The interesting thing about this diagram is that only the lower layers in this model contain the Java components that need to be coded All other layers and objects in this model are pre built You just assemble them together in a certain way and customize their behavior by changing the component s properties in the ABC tool An application is built using the divide and conquer idea of assembling a complex application from smaller and simpler components Thus for example activities and resources are built based on the Java components that are implemented by a Java developer EJBs servlets JavaBeans and so on The activities and resources
232. n t implement it fully You can find more information about the J2EE platform specification versions 1 2 and 1 3 on the Web at http java sun com j2ee CORBA development for EJBs If the EJB is in the role of the CORBA client the process is exactly the same as described in CORBA development on page 156 If EJB is in the role of the CORBA server the programming model is different from the standard CORBA programming model The IDL is not the starting point for the development process but derived from the EJB classes The steps are 1 Develop your EJB just as you would without CORBA 2 Create the IDL from the EJB and the EJB home classes with a reverse IDL compiler 3 Compile the IDL files with an IDL compiler for the client stub 4 Develop the client program a Develop the main code that invokes the EJB methods b If serializables are part of the EJB Interface they have to be implemented as CORBA valuetypes in the client language 5 Build the client with a language specific compiler linker and archiver 158 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 8 2 Overview of WebSphere Application Server Enterprise Edition CORBA support The CORBA support in WebSphere Application Server Enterprise Edition is the implementation of the J2EE CORBA services and supports CORBA 2 1 as well as valuetypes from CORBA 2 3 In addition CORBA support includes the proven interoperability with major CORBA p
233. n service using JNDI Then the interfaces to the caller and invocation contexts are retrieved Example 6 4 Binding to the Internationalization service import com ibm websphere il8n context import javax naming private UserInternationalization il8nService private Internationalization callerI18N private InvocationInternationalization invI18N public ItemsViewBean InitialContext jndi null Bind to Internationalization facility try jndi new InitialContext i118nService UserInternational ization jndi lookup java comp websphere UserInternational ization This exception indicates a problem binding to the facility catch NamingException e e printStackTrace Bind to the desired interfaces try callerI18N i18nService getCallerInternationalization invI18N i18nService getInvocationInternational ization This exception indicates the service is disabled catch I llegalStateException e 112 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide e printStackTrace Tip Internationalization context API references need to be resolved only once over the life cycle of any application component When developing server side application components like servlets and Enterprise JavaBeans bind to the Internationalization service within the initialization methods of these components for example within the init method of servlets or within the ejbSetConte
234. n context management The Internationalization service transparently propagates locales and time zones across J2EE clients Enterprise JavaBeans JSPs and servlets The context management policies of the service determine how the internationalization context is propagated The following context management policies are applied depending on whether an application component is contained on the client side or the server side Client side Internationalization CSI policy Only EJB client application components deployed within J2EE client containers are subject to the Client side Internationalization policy In CSI client applications can get and set the invocation context locale and time zone elements associated with the current thread using the InvocationInternationalization interface Invocation context elements set by the client persist until they are set again or until the application exits Clients may also get the caller context elements associated with the current thread In a client application caller context is always the default locale and time zone of the client s JVM On the remote method calls to EJBs originated from a J2EE client application the Internationalization service propagates all invocation context elements associated with the current thread to the outgoing request If an invocation context element was set using the InvocationInternationalization interface the service propagates the specified element Otherwise the servic
235. n directory for WebSphere Application Server for example C IBM WebSphere AppServer We use the WAS_HOME and OE_HOME defined later in the appendix environment variables throughout the book to specify the installation directories for WebSphere Application Server and the OrderEntry application respectively All instructions throughout this book assume the environment described above If you use a different environment adjust the instructions in the book accordingly Downloading the OrderEntry application ZIP file The OrderEntry application ZIP file contains all the setup files source and compiled code To download the file you need to perform the following steps 1 Open the IBM Redbooks Web page at http www redbooks ibm com 2 Type SG24 6504 in the search window and click Search 3 Follow the link for this redbook 4 5 Save the ZIP file on your system In the Web page click the Additional Materials link in the right part of the window Unzipping the file Follow these steps to unzip the OrderEntry ZIP file 1 2 3 Open the OrderEntry ZIP file in WinZip or a similar program Unzip the OrderEntry ZIP file to any directory for example C OrderEntry Add the environment variable OE_HOME Set the value of OE_HOME to the directory name to where you unzipped the file For example set it to C OrderEntry 222 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Description of t
236. n specified in the JMS Listener configuration file The message bean is responsible for processing the message It is good practice when programming a message bean to delegate business functions to another EJB This provides a clear separation of message handling and business processing The message bean may perform processing within the scope of a transaction The current implementation of a message bean uses a stateless session EJB IBM s future direction with regard to messaging is to enable support for Message Driven Beans MDBs as defined within the EJB 2 0 specification To be treated as a message bean your EJB must have an onMessage method which should maintain the following rules The method must be declared as public The method must not be declared as final or static The return type must be void The method must have a single argument of type javax jms Message The throws clause must not define any application exceptions public void onMessage javax jms Message incomingJMSMessage YYYY Y It is also worth considering the function provided in the ejbCreate and ejbRemove methods For these methods we recommend that they follow the Message Driven Beans requirements The method must be declared as public The method must not be declared as final or static The return type must be void The method must not have any arguments The throws clause must not define any application exceptions YYYY Y In addition f
237. nch BRBeans classpath and paste it into the classpath file located in BRBeans project in WebSphere Studio Application Developer see Figure A 1 This step sets up the class path for the projects with the references to all required directories and JAR files J2EE Application Developer File Edit Perspective Project Window Help ASvyIBBS NARDS D BRH LID S 7 45 ga E od lt xml version 1 0 encoding U0TF 6 72 gt n lt classpath gt ty BRBeans lt classpathentry kind var path SERVERJDK_PLUG a bin rootpath sre sourcepath SERVERJDK_PLUGIN ejbModule lt classpathentry kind sre path ejbModule gt C lt classpathentry kind var path WAS_PLUGINDIR G Deployed_OrderEnt lt classpathentry kind var path WAS_PLUGINDIR Te OrderEntry lt classpathentry kind var path WAS_PLUGINDIR lt classpathentry kind var path WAS_PLUGINDIR lt classpathentry kind var path WAS PLUGINDIR J2EE View Navigator ao lt classpathentry kind var path Outline x n outline is not available Search Tasks Properties BRBeans classpath Figure A 1 Editing a classpath file Appendix A Downloading and installing the OrderEntry application 223 Setting up the databases You need to set up two databases gt gt The OrderEntry application database The BRBeans database
238. ndow expand WebSphere Administrative Domain gt Nodes gt node gt Application Servers gt application_server The properties related to the selected application server are displayed in the right hand pane Note node represents the node on which the application server is located and application_server represents the name of the application server for which you are enabling the service 2 In the right hand pane click the Custom tab see Figure 6 1 If the Custom tab does not list the Internationalization Service entry you must add a new entry for Internationalization Service Go to step 3 If the Custom tab lists the Internationalization Service entry you can view and edit the Internationalization Service properties Go to step 4 General Advanced File Transaction JVM Settings Services Custom Service Enabled Add Automatic Generation of Plugin False WorkArea Service True i Remove Extended Messaging Support Se True Internationalization Service Apply Reset Help Figure 6 1 Custom tab with Internationalization Service selected 3 Add a new Internationalization Service entry to the Custom tab a On the Custom tab click Add The Add Custom Service dialog is displayed b In the Add Custom Service dialog enter the properties as shown in Figure 6 2 c Click OK The Add Custom Service dialog closes d Click Apply Your changes are saved 4 Verify or ed
239. ng scenarios gt Third party C CORBA client to WebSphere Application Server EJB server gt WebSphere Application Server EJB server as CORBA client to a third party CORBA ORB IBM supports interoperability with its CORBA products for various scenarios These support statements are the result of controlled tests in specifically identified environments and focus around the IIOP interoperability The supported products are listed in Table 8 1 Chapter 8 The CORBA services 159 Table 8 1 Client Server ORBs that interoperate with WebSphere Application Server 4 0 ee cies sener tet Sener Windows NT 3 0 1 C 3 0 1 C 3 3 3 C 3 3 3 C Windows 2000 Web 3 2 Java 4 0 C 3 4 Java 2000 1 2 C 4 1 C 4 0 C 4 0 Java 4 1 C 3 0 1 C 3 3 3 C 3 3 3 C Web 3 2 Java 4 1 C 3 4 Java 2000 1 2 C 4 0 Java 4 1 C Solaris 7 3 0 2 C 3 0 2 C 4 0 C 3 4 Java Web 3 2 Java 4 1 C 4 0 C 2000 1 2 C 4 0 Java 4 1 C The tests that demonstrate interoperability are shipped with WebSphere Application Server as the interoperable sample code You can run these tests to see which data types exactly interoperate and which do not They can be used to verify that ORBs other than those supported by IBM interoperate Note that verifying interoperability with the sample code is not a statement of support by IBM for that ORB For our example clients and server we used newer versions of VisiBroker and Orbix 2000 other than the sup
240. ng the Connection oTopicConnection start Create a TopicSession from the TopicConnection Not transacted and that it should automatically acknowledge received messages System out printIn Creating a Session boolean transacted false oTopicSession oTopicConnection createTopicSession transacted Session AUTO_ ACKNOWLEDGE Use the session to create a TopicPublisher passing in the destination the Topic object as a parameter System out print n Creating a TopicPublisher oTopicPublisher oTopicSession createPublisher oTopic Use the TopicSession to create messages create an empty TextMessage and add the data passed System out println Creating a TextMessage TextMessage outMessage oTopicSession createTextMessage text Ask the TopicPublisher to publish the message we have created System out print n Publish the message to oTopic getTopicName oTopicPublisher publish outMessage Closing TopicPublisher System out printIn Closing TopicPublisher oTopicPublisher close Closing Session System out printIn Closing Session oTopicSession close oTopicSession null Closing Connection System out print n Closing Connection Chapter 4 Extended Messaging Service 83 oTopicConnection close oTopicConnection null System out printIn End of Sample catch
241. nging the modes In a nested WorkArea you can override the values of properties in the original WorkArea that was not marked with the read only mode You can also override the mode of the properties in the nested WorkArea depending on the mode they were set with in the original WorkArea Table 5 2 lists the mode changes that are possible in the nested WorkArea Table 5 2 Permissible mode changes in a nested WorkArea Mode in an enclosing WorkArea Possible mode change in a nested WorkArea Read only No changes allowed unless a property is removed first and then re created with any of the four modes Fixed read only No change allowed Remember that the mode is not actually changed in the original WorkArea What happens is that the new mode in the new nested WorkArea overrides the mode in the original WorkArea When the remote method completes the new nested WorkArea and returns the modes return to their original values before the remote method call 5 3 4 Other methods defined by the UserWorkArea interface Example 5 9 shows the complete definition of the UserWorkArea interface Example 5 9 Complete definition of the UserWorkArea interface package com ibm websphere workarea public interface UserWorkArea void begin String name void complete throws NoWorkArea NotOriginator String getName String retrieveAllKeys void set String key java io Serialazable value throws NoWorkArea NotOriginator PropertyRea
242. nnection factory Defined as WSQCF in the JMSAdmin tool supports transactional messaging where messages can be placed back on the queue in the event of message bean processing failure Chapter 4 Extended Messaging Service 59 4 2 4 WebSphere Application Server 60 The naming server within WebSphere Application Server is used to locate all JMS resources via JNDI It also manages the JMS Listener and message beans The JMS Listener service is hosted by WebSphere Application Server At run time it uses the XML configuration file to create listeners Each listener invokes a specified message bean when a message arrives at an associated JMS destination queue JNDI entries are used to locate all JMS resources These entries must be entered into WebSphere Application Server to enable JNDI lookup of the resources Figure 4 10 shows WebSphere Application Server in relation to the JMS Provider and the XML configuration file The XML tags found in the file relate to JMS resources whose entries are found in the JNDI namespace managed by WebSphere Application Server The JNDI name of the message bean is also managed by WebSphere Application Server JMS Provider MQSeries Send JMS Definition q correlation Websphere Application Server Send JMS JNDI Entries Listen JMS definition q correlation Listen JMS JNDI Entry WAS QCF Definitions wsqcf correlation
243. not fully specify the server objects The Basic Object Adapter BOA left a lot of room for interpretation Since the Portable Object Adapter POA has been fully specified interpretation has been reduced but interoperability is still an issue Apart from the ORB there are two other key building blocks in the CORBA model gt Interface Definition Language IDL gt CORBA services The IDL describes the object services and normalizes the differences caused by language or operating system dependencies CORBA services provide standard ways for CORBA objects to interact Examples of CORBA services include naming transaction event and notification CORBA is independent of the programming language To use the ORB it is necessary for programmers to know how to access ORB functionality from their programming languages CORBA Language Mapping specifications define the mapping of IDL constructs to several programming languages There exist language mappings for Java C C Smalltalk Ada Lisp COBOL Python and CORBA Scripting Language The most recent release of the specification is CORBA 2 5 but release 3 0 is planned to be finished in soon But most of the vendors have products that do not comply to a newer release than 2 3 at the moment Locating a server object A key topic in the CORBA model is how a client locates its server object There are several ways to do this but the standard way would be to use the CORBA Naming Service The
244. nstraintReturn The top level validation rule can invoke individual validation rules and report results to the rule client 3 3 Performance considerations Every business rule is represented as an EJB at runtime As a result the BRBeans framework has to repeatedly execute two tasks to find the rule gt Perform a query to find a rule gt Perform a remote method call to fire the rule These operations can be costly from the performance perspective This section discusses the techniques that can be used to improve performance Caching We can eliminate the need to perform a query to find a BRBeans rule with the use of the client side cache The client side cache stores the results of all queries performed to find rule EJBs After the initial call to the BRBeans rule has been made all subsequent calls use the rule stored in the cache Cache scope is limited to the JVM in which the client is running The disadvantage of using the client side cache is the inability to recognize BRBeans rule configuration changes immediately A cache polling frequency determines how often the client side cache is refreshed The default polling frequency is 10 minutes You can change the polling frequency in the Rule Management Application 1 Start the Rule Management Application if it is not already started see 3 2 1 Setting up the development environment on page 19 2 Expand the Rule Namespace folder 3 Expand the com gt ibm gt websphere gt
245. nt To build the client you simply have to run a makefile by executing the following two commands cd 0E_HOME corba client vb2ejb nmake f makefile vb2ejb This command executes all the steps that are described in the following subsections Create the IDL files Merge the IDL files Compile the IDL files Compile and link the stubs Build the tools library Build the main object and link the executable Build the IOR tool DY OBS GON We show the output of the commands that are executed by the makefile You don t have to execute any of the commands manually But you could do so if you are interested in building the client manually step by step The nmake command is described in detail in the online documentation of Microsoft Visual C The makefile ibm2ejb file executes all the steps that are described in the following subsections nmake may execute the commands in a different order because it doesn t follow a sequence of commands but resolves dependencies To delete all the generated files and directories you call cd 0E_HOME corba client vb2ejb nmake f makefile vb2ejb clean Creating the IDL files The IDL files were created in the same way as described in Creating the IDL files on page 166 But they have to be edited manually before they can be compiled by idl2cpp the IDL compiler of VisiBroker We have to do that because gt VisiBroker does not have a valuetype library like WebSphere Application Server
246. nt C clients for the already existing customer EJB of the OrderEntry application The clients have restricted access to the methods of the home interface see EJB as a CORBA server on page 161 and full access to the remote interface of the CustomerBean The clients can Create a customer Delete a customer Get detail information of a customer Set detail information for a customer Find a customer by a customer key object YYYY Y You could imagine another legacy application that needs to get or update customer information The development process for both clients in general follows the steps that are described in CORBA development for EJBs on page 158 8 3 1 Configuring the environment We used the following environment for our sample clients Windows 2000 SP 1 WebSphere Application Server V4 0 1 Enterprise Edition Microsoft Visual C 6 0 Inprise Borland VisiBroker 4 5 YYY Yy The installation and configuration of Windows WebSphere Application Server and Microsoft Visual C are not covered in this redbook These are described in the product specific installation guides The subdirectory VC98 of the MS Visual C installation is referred to as MSVCDir in the following sections Prerequisites The following general prerequisites must be fulfilled 1 Extract the ZIP file containing the CORBA sample code a directory 2 Set the environment variable OE_HOME to the directory where the ZIP file was extracted
247. nterpretation may depend on the View and invokes the appropriate operation of the Model For example when the Controller detects a mouse click event on the Remove button of an item it invokes the remove operation on that item Any state changes that this operation effects on the Model are sent by the Model to the registered Views via events and EventObjects WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Keyboard Controller 7 7 1 register as observer 2 operation 7 3 notify eventObject Figure 7 3 MVC pattern The MVC pattern enables the combination of a single Model with multiple Views and Controllers The MVC pattern ensures that the Views are kept synchronized as can be seen from the following example One of the Controllers recognizes a valid command from the user s input The Controller invokes the corresponding method on the Model The Model verifies that the operation is compatible with the current state executes it and changes the state correspondingly The state change triggers an event that the Model multicasts to each View To support multiple Views and Controllers dependencies must be kept minimal Another precondition to support multiple Views and Controllers is to keep interactions minimal In particular a Controller must never directly affect the rendering of its associated View Instead a user input must make a complete round trip through
248. ntext 215 keep alive process 214 loosely coupled connection 211 message cluster process 214 outcome 212 Outcome decider 215 Outcome decider context 215 Outcome Mapper 215 OutIn Port 213 Output Port 213 port 213 process 212 213 Process context 215 programming model 212 repeat process 214 resource 214 Resource context 215 retry process 214 sequential process 214 source cluster process 214 swap process 214 task 212 the LocalClientContext object 219 time limit process 214 Unit of Work UOW Director 214 BPBeans Business Process Beans 3 BRBeans 16 base rules 18 benefits 16 classification rules 18 combining strategy 35 37 components 16 configuring business rules 23 235 creating rule implementors 23 deployment 47 EJBs 16 17 filtering strategy 35 finding strategy 35 framework components 16 general approach for implementing business rules 22 identifying business rules 18 implementing a business rule with dependent rules 41 implementing a classifier rule 26 implementing base rule 32 implementing business rules 18 overview 16 performance considerations 46 Quick Copy 23 Rule Importer and Exporter 17 Rule Management APIs 17 rule states 25 setting up the development environment 19 strategies 32 37 strategy objects 24 TriggerPoint 17 BRBeans Business Rules Beans 3 BRBeans EJBs 16 BRBeans performance caching 46 database indexes 47 firing location 47 BRBeans rule 16 25 firing location 26 BRBeans Rule Implementors 16
249. nts V vi 8 4 2 Connecting to an Orbix server 0 00 eee 190 8 4 3 Problem determination 0 cee eee 206 Chapter 9 The Business Process Beans service 22200005 209 9 1 BPBeans basles iesenii kota ie a ae iw we Hod ea be as 210 9 2 BPBeans programming model 0 0 cee ee 212 92T TASK a a a E E cotter geek ate entice Go Me end dd nae ee dey ea ete Ad aoe 212 9 2 2 ROSOULCE ment a a a dey hese kate BA acta sea cael Angie naa eens 214 923 COMEX 2 2500 boda ayer wha Pee elo deen ee en dee eyelet EES 215 9 2 4 Outcome decider 0 ee tees 215 9 3 Generic steps in BPBeans development 0 00 eee eee eee 216 Appendix A Downloading and installing the OrderEntry application 221 Setup INStUCTIONS seco eat eee ee ew Geen a a ate gy eed eke aes 222 ENVIrONMEN U rii Seah ehatah aid n ah aao a e eh pag Mee eee Sea aa naga ed ahaa 222 Downloading the OrderEntry application ZIP file 0 0 0 0 eee eee 222 Unzipping the file 2 0 0 eee i eee dad oe aoe ed ea i aoe ded 222 Description of the directory structure 6 6 eae 223 Setting up the databases 2 0 eee eee 224 Setting up the OrderEntry application database 00 ee eee eee 224 Setting up the BRBeans database 0 cee tee 224 Configuring WebSphere Application Server 20 000 eee 224 Installing the OrderEntry application 0 0 eee 226 Importing
250. number and so on Order information date time shipper and so on Order line information quantity delivery date and so on Item information name price item ID and so on Stock information quantity in stock warehouse ID and so on 2 1 3 A customer transaction A customer transaction occurs based on the following series of events 1 2 Customers telephone one of the 10 district centers to place an order The district customer service representative answers the telephone obtains the following information and enters it into the application Customer number Item numbers of the items the customer wants to order The quantity required for each item The customer service representative may prompt for a list of customers or a list of parts The application then performs the following actions a Reads the customer last name customer discount rate and customer credit status from the Customer Table CSTMR b Reads the District Table for the next available district order number The next available district order number increases by one and is updated c Reads the item names item prices and item data for each item ordered by the customer from the Item Table ITEM d Checks whether the quantity of ordered items is in stock by reading the quantity in the Stock Table STOCK When the order is accepted the following actions occur a Anew row is inserted into the Order Table to reflect the creati
251. nvironment variable JAVA_HOME to the value of WAS HOME java Note Microsoft Visual C 6 0 is the only C compiler that is officially supported by Orbix 2000 V2 0 see the prerequisites in the IONA Orbix 2000 Installation Guide 188 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide You have to configure Orbix 2000 after the installation The configuration concept of Orbix 2000 is described in the IONA Orbix 2000 Administrator s Guide C Edition in the chapters Selecting a Configuration Model and Configuring Orbix 2000 which is available at http www iona com docs orbix2000 2 0 admin_cpp htm1 index html For the OrderEntry application we use a simple local and no distributed configuration However you can create several configurations and activate them if necessary To create a configuration domain in Orbix 2000 you should follow these steps 1 Start the visual configuration tool by entering the following commands in a command prompt cd lt orbix_home gt orbix_art 2 0 bin itconfigure 2 Select Create a configuration domain from the pop up window 3 In the next screen complete these tasks a Enter a name for the domain like OrderEntry b Select the Standard services radio button c Select the Include configuration for demo applications check box Click Next Select Local File and click Next Leave the host properties as they are and click Next Leave the infrast
252. nvocationInternationalization extends Internationalization public void setLocales java util Locale locales public void setLocale java util Locale locale public void setTimeZone java util TimeZone timeZone public void setTimeZone String timeZoneld Since the InvocationInternationalization interface extends the Internationalization interface all methods from the Internationalization interface are available in the InvocationInternationalization interface In addition the InvocationInternationalization interface defines four more methods gt void setLocales java util Locale This method sets the array of locales associated with the current thread to the supplied array of locales The supplied locale array can be null or have length greater than or equal to zero When the supplied locale array is null or has length of zero the Internationalization service sets the array of locales to an array length of one containing the default locale of the process associated with the execution of this method Null entries can exist within the supplied array of locale However on the remote method invocations the Internationalization service substitutes all null elements with the default locale of the process associated with the execution of this method gt void setLocale java util Locale This method sets the array of locales associated with the current thread to an array of length one containing the supplied locale If the supplied lo
253. nvolved classes are the same as for the IBM client Figure 8 7 on page 170 shows the class diagram You find the source code of the described classes in the directories 0E_HOME corba client vb2ejb 0E_HOME corba client vb2ejb com ibm itso roch wasaejb 0E_HOME corba tools Initializing the VisiBroker ORB After the main method reads the program parameters the ORB is initialized This is done inside the constructor of the MyOrb class Example 8 5 shows the code Example 8 5 Initializing the VisiBroker ORB MyOrb MyOrb string iorFileName initOrb _rootIOR readIOR iorFileName Root Naming Context void MyOrb initOrb int intO 0 Initialize the ORB try t printIn Initializing the ORB _orb CORBA 0RB_init int0 NULL Chapter 8 The CORBA services 183 Note that the initialization is slightly different from the one for the IBM client in Example 8 1 on page 171 In addition the string version of the naming services root IOR has to be read from the file as shown in Example 8 6 Example 8 6 Reading the stringified root IOR string MyOrb readIOR string fileName string what Trace t Error err char ior 10240 t printIn Reading the what IOR from fileName ifstream in fileName c_str if lin err println Can not open File fileName else in gt gt ior in close return ior Getting the root context by resolving the stringified IOR
254. o methods one is to add an input port listener and another is to remove an input port listener Any component that implements the com ibm bpbeans InputPortListener interface can register with an input port in order to receive a message In simple cases when there is only one BPBeans component on the input port you can use a shortcut by assigning a value to the property called Input Method which is described next gt The property Input Method defines the name of the method that should be invoked when a message arrives to an input port This property is used when you have only one component listening on the input port In our example the property is set to setInputMessage This method is part of the activity class ReceiveActivity not the InputPort interface Basically this property provides a shortcut for routing an incoming message directly to the activity bypassing the input port object gt The input parameter type aka Java class name of the input parameter is declared as the Data type property and it is set to com ibm bpb tutorials MessagePassing DateMessage The BPBeans framework provides the com ibm bpb base ActivityBase class that implements the com ibm bpbeans Activity interface In most cases you need to extend this class in order to create your new Activity The com ibm bpb base ActivityBase class provides the implementation of the required methods for the Activity components Plus it adds several utility methods that
255. of WebSphere Application Server have the same code base This means that customers can upgrade WebSphere Application Server more easily gt WebSphere Application Server is Java 2 Platform Enterprise Edition J2EE Version 1 2 certified This means that it supports the Java standards that are part of the J2EE specification However IBM goes beyond the J2EE specifications and offers extended services some of them are part of the new Version 1 3 of J2EE in WebSphere Application Server Enterprise Edition gt WebSphere Application Server Enterprise Edition consists of four major elements WebSphere Application Server Advanced Edition Version 4 0 WebSphere Enterprise Services IBM services are aimed at sophisticated Java developers whose needs go beyond the current Web services and J2EE standards By offering a collection of leading edge Enterprise Services that plug into and augment the core WebSphere Application Server Version 4 0 Advanced Edition product IBM adds significant value to the base application server These Enterprise Services provide customers the flexibility they need to quickly develop and adapt e business applications to meet emerging business requirements IBM TXSeries Supports the traditional procedural programming model TXSeries is middleware used in a high performance distributed transaction processing environment When sheer high speed transaction processing is the goal TXSeries provides the solution in Dist
256. ogic for accessing a data source Outcome Decider If you plan to use Concurrent Process you need to develop Outcome Decider It has to implement the com ibm bpbeans OutcomeDecider interface By analogy with other components the BPBeans framework has a class that implements the com ibm bpbeans OutcomeDecider interface As a result it is easier to extend the com ibm bpb base OutcomeDeciderBase class Outcome Set and Outcome Mapper The BPBeans framework provides numerous classes for Outcome Set and Outcome Mapper In most cases you use supplied classes However if you want to create a new component follow this guideline e Outcome Set has to implement the com ibm bpbeans OutcomeSet interface For ease of use the BPBeans framework provides the implementation of two classes com ibm bpb base FiniteQutcomeSetBase and com ibm bpb base InfiniteQutcomeSetBase Use one of them for your Outcome Set 216 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide e Outcome Mapper has to implement the com ibm bpbeans OutcomeMapper interface To facilitate the development process the BPBeans framework supplies the com ibm bpb base QutcomeMapperBase class that should be extended 3 Import all the components that you developed in the previous step into the ABC tool 4 Add the description for all developed components 5 Wrap Activities Resources and Outcome Decider into the corresponding context Activi
257. ols dll library link DEBUG NOLOGO INCREMENTAL NO LIBPATH 0E_HOME corba client vb2ejb LIBPATH 0E_HOME corba tools LIBPATH VBROKERDIR lib Customer 1ib DLL tools exp Trace obj Error obj Warning obj MyOrb obj CustomerWrapper obj CustomerFactory obj OUT tools d1 cd 0E_HOME corba client vb2ejb move 0E_HOME corba tools tools d11 Building the main object and linking the executable The main class is vb2ejb cpp Beside the tools and stubs libraries it uses a helper class to read the program arguments The makefile executes the following steps Chapter 8 The CORBA services 181 1 Compile the main object The following output is generated x Generating the vb2ejb obj object cl 1 0E_HOME corba client vb2ejb 1 0E_HOME corba tools I MSVCDir include 1 VBRODERDIR include 1 VBRODERDIR include stubs DWIN32 D_USE NAMESPACE nologo MD GX c DORB_ VisiBroker vb2ejb cpp vb2ejb cpp Customer_merged_c hh 24 warning C4067 unexpected tokens following preprocessor directive expected a newline Customer_merged_c hh 27 warning C4067 unexpected tokens following preprocessor directive expected a newline Compiling the ProgVals class cl 1 0E_HOME corba client vb2ejb 1 0E_HOME corba tools I MSVCDir include 1 VBRODERDIR include 1 VBRODERDIR include stubs DWIN32 D_USE_NAMESPACE nologo MD GX c DORB_VisiBroker ProgVals cpp ProgVals cpp 2 Link the executable which produces the output L
258. on of the new order ORDERS b A new row is inserted into the Order Line Table for each item in the order c The quantity in the Stock table is reduced by the quantity ordered d Aconfirmation message is returned to the customer service representative Anemployee at the fulfillment center accesses the Order table and ships the merchandise based on the incoming orders 2 1 4 Application flow To better understand the application s logic we provide the OrderEntry application flow diagrams The overall flow of the execution of a customer order request is divided into three diagrams gt Getting customer information Figure 2 2 gt Adding selected items to the shopping cart Figure 2 3 on page 9 gt Checking out Figure 2 4 on page 10 Chapter 2 Overview of the OrderEntry application 7 The first diagram getting customer information is presented in Figure 2 2 Customer begins order mA E _ Customer ane a OrderEntrySerlet ApplicationMgr ItemsViewBean com ibm itso roch wasaejb Customer GetCustomer jsp Orderltems jsp gef from session or create get fforn session or create startNewOrder getCust omer lookup EJB create setCustomer displayJSP If customer was not found displayJSP Customer j has been found i i i i i Figure 2 2 Getting customer information
259. on page 19 Expand the Rule Namespace folder Click the CustomerRules folder Select the Specials rule with the Gold classification Right click and select Properties Inthe Properties window select the Implementation tab Click the Add button next to the Initialization parameters box gt Oo 20 oc Fill out the required fields e Description Gold customer special e Type String e Value Free shipping with a purchase of over 100 g Click OK 7 Test the application with the user ID 0002 The results are displayed in Figure 3 17 1 90 day interest free financing 2 Appreciation gift with a purchase of over 50 3 Free shipping with a purchase of over 100 Figure 3 17 Modified Gold customer specials 3 2 5 Implementing a business rule with dependent rules Some complex business processes are composed of several business rules We can model this behavior in the BRBeans framework We simply use one BRBeans rule to represent the process and one or more dependent BRBeans rules to represent the various units of the composition Chapter 3 The Business Rule Beans service 41 42 To demonstrate the use of dependent rules let s review the implementation of this business rule The total order amount is determined by 1 Getting the actual purchase amount 2 Subtracting discount 3 Adding the tax 4 Adding the shipping charge Rule implementations In WebSphere Studio Application Developer expand the OrderEn
260. ontaining the CORBA sample code to a directory 2 Set the environment variable OE_HOME to the directory where the ZIP file has been extracted 3 Make sure that Microsoft Visual C is installed in the default directory C Program Files Microsoft Visual Studio VC98 If it is not you have to edit the environment file OE_HOME corba set_common_env bat Configuring Orbix For this example we used a 30 day evaluation version of Orbix 2000 V2 0 The following setup is described based on this experience The details might slightly differ if you use a full version of the product All the online documentation such as the installation administrator s and developer s guides for Orbix 2000 is available at http www iona com docs orbix2000 2 0 index htm To install Orbix 2000 you have to follow these steps 1 Register at http www iona com forms orbix2000_eval_form htm 2 Download the software a Download the development package for Windows 2000 b An additional window shows a link from where you can download the runtime package 3 Install the packages like those that are described in the JONA Orbix 2000 Installation Guide the chosen directory is referred to as lt orbix_home gt 4 License the software a After registering you receive mail with the license key as an attachment The easiest way of licensing is to detach the file to the directory lt orbix_home gt etc b Rename the file to licenses txt 5 Set the e
261. ontains no functionality the initonly parameter of the client container is set to true by the ActiveX process before the container is launched This prevents the Main class s main method from being invoked However even though this class is never called the container will throw an error on launch unless the Main class exists You must follow these rules when setting up the Main class gt Theclass must be in the client JAR gt There must be an entry in the client s Manifest MF to indicate the name and path of the file For example if the name and path is MyApp DummyClient class with respect to the client JAR s root the entry in the Manifest MF file would be Main Class MyApp DummyClient gt The file must have the same name as the class it contains gt Itis not necessary for the class to have a main method although the code for DummyCl ient in Example 7 17 does Example 7 17 The DummyClient class with the no op main public class DummyClient public static void main String args Do nothing 148 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 7 8 2 Creating the dummy client JAR The creation of the client JAR is the easiest to achieve using the Application Assembly Tool AAT Start the AAT and open the server EAR file Click the Wizards icon and select Create Application Client wizard Use the drop down list next to Containing Application to select the EAR file
262. oot context by bootstrapping Binding the CustomerHome Creating a customer YYYY Y Class overview Figure 8 7 shows an overview of the involved classes and how they are related The classes Customer CustomerHome and CustomerKey are generated Therefore they are displayed in a different style Customer ProgVals main Factory Customer Trace Wrapper Error A Customer Key_Impl Warning Fatal Figure 8 7 Class diagram for ibm2ejb 170 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide You can divide the classes into two groups gt IDL generated classes Customer CustomerHome CustomerKey gt Manually created classes main CustomerWrapper CustomerFactory CustomerKey_Impl MyOrb ProgVals Trace Error Warning Fatal You find the source code of the described classes in the directories 0E_HOME corba client ibm2ejb 0E_HOME corba client ibm2ejb com ibm itso roch wasaejb 0E_HOME corba tools Initializing the IBM ORB After the main method has read the program parameters the ORB is initialized This is done inside the constructor of the MyOrb class Example 8 1 shows the code Example 8 1 Initializing the IBM ORB CORBA ORB_ptr _orb void MyOrb initOrb int intO 0 Initialize t
263. or your message beans you should avoid standard session programming practices that will inhibit the migration of message beans to MDBs specifically gt Do not write any standard EJB client code You should never look up the JMS Listener s home interface in any of your application code or obtain a handle for the home interface MDBs do not have a home interface gt Do not implement any create methods on the home interface other than the create method with no arguments This is typically not done on stateless session beans but is also not explicitly prohibited by the EJB 1 1 specification Chapter 4 Extended Messaging Service 67 68 gt Do not implement any additional business methods beyond the onMessage method in the message bean s remote interface MDBs do not have a remote interface Note that it is okay to have additional supporting methods on the bean itself just do not count on them being callable anywhere outside of the listener itself To this end you should consider making all supporting methods private gt Do not write any code in a message bean that uses the optional SessionSynchronization interface This interface is not supported by MDBs gt Isolate your use of getSessionContext calls appropriately MDBs will have a getMessageDrivenContext method instead that will return a javax ejb MessageDrivenContext object We developed a message bean StockDeliveryUpdate that processes all messages fro
264. org ant manual index htm gt Java2 Platform Enterprise Edition Web site http java sun com j2ee gt JavaTM 2 SDK Standard Edition Version 1 3 1_02 for Microsoft Windows http java sun com j2se 1 3 download windows htm How to get IBM Redbooks Search for additional Redbooks or Redpieces view download or order hardcopy from the Redbooks Web site ibm com redbooks Also download additional materials code samples or diskette CD ROM images from this Redbooks site Redpieces are Redbooks in progress not all Redbooks become Redpieces and sometimes just a few chapters will be published this way The intent is to get the information out much quicker than the formal publishing process allows IBM Redbooks collections Redbooks are also available on CD ROMs Click the CD ROMs button on the Redbooks Web site for information about all the CD ROMs offered as well as updates and formats 234 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Index Symbols lt Listener gt XML tag 66 A ABC Application Builder for Components 210 ACID transaction 210 Active Server Pages 122 ActiveX 121 ActiveX bridge 3 dummy client JAR file 149 accessing Java objects methods and fields 133 client container approach 129 client interface 126 components of the client side EAR file 131 initializing the JVM 128 launching client container in an ActiveX process 131 launching standard Java J2EE application in clien
265. ory structure 223 development environment 14 downloading and installing 221 environment 222 importing the BRBeans rules 228 installing 226 introduction 6 running the OrderEntry application 229 setting up databases 224 tables 10 Outcome decider context 215 outcome set 212 P physical queue 55 POA 195 POA portable object adapter 196 POA_Manager 195 238 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide point to point messaging model 51 point to point model 52 polymorphism 138 portable object adapter POA 196 PowerBuilder 123 primitive data type conversion 133 Process context 215 property 92 publish subscribe messaging model 51 publish subscribe model 53 76 Q queue connection factory 59 Quick Copy 23 R read only mode 97 Redbooks Web site 234 Contact us xi Reflection API 139 repeat process 214 Resource context 215 retry process 214 return value 139 RMI IIOP 158 root context 171 184 197 205 rule client 16 rule client implementation 35 rule implementor 16 22 23 rule implementor class 26 Rule Importer and Exporter 17 Rule Management APIs 17 Rule Management Application 16 22 23 28 32 Quick Copy 23 rule state 25 Rulelmplementor 16 fire method 27 init method 26 interface 23 S scheduled rule state 25 security 88 send and receive size 103 sequential process 214 serializable 158 servant 155 197 servant object 156 server application component 107 server objec
266. output xxx Extracting the EJB jar file from the ear file jar xvf 0E_HOME Order_Entry_Application ear Deployed_OrderEntryEJB jar extracted Deployed_OrderEntryEJB jar x Extracting the Customer class from the EJB jar file jar xvf Deployed_OrderEntryEJB jar com ibm itso roch wasaejb Customer class extracted com ibm itso roch wasaejb Customer class xxx Extracting the CustomerKey class from the EJB jar file jar xvf Deployed_OrderEntryEJB jar com ibm itso roch wasaejb CustomerKey class extracted com ibm itso roch wasaejb CustomerKey class x Extracting the CustomerHome class from the EJB jar file jar xvf Deployed OrderEntryEJB jar com ibm itso roch wasaejb CustomerHome class extracted com ibm itso roch wasaejb CustomerHome class 2 Create the IDL files The output is Creating the Customer IDL rmic J Djava ext dirs WAS HOME 1lib WAS_HOME Enterprise lib idl com ibm itso roch wasaejb Customer Creating the CustomerKey IDL rmic J Djava ext dirs WAS HOME 1ib WAS_HOME Enterprise lib idl com ibm itso roch wasaejb CustomerKey x Creating the CustomerHome IDL rmic J Djava ext dirs WAS HOME 1ib WAS_HOME Enterprise lib idl com ibm itso roch wasaejb CustomerHome Compiling the IDL files The client stub files are built from IDL files For example they do the data type marshalling and have to be linked to the main executable makefile ibm2ejb generates the client stubs that produce the follow
267. ows the VisiBroker Console 5 Borland isiBroker Console i lol x File View Tools Help TEHDA e gt VisiBroker ORB Services N Pal D Location Serice s E Naming Services A Interface Repositories fal 8 E Implementation Repositories Location Santee Naming Services I m Server Managers i H Gatekeepers K Eel j Interface Repositories Implementation Repositories fal ie Server Managers Gatekeepers Tn Done 14000 49 Borland Figure 8 6 VisiBroker Console It is a browser for the ORB services The smart agent which is the basic locator process in VisiBroker and other services can be started from the windows menu bar via Programs gt VisiBroker or from the command line The VisiBroker Console and the administration of the VisiBroker services are described in detail in the programmer s guide in Part IV Configuration and management 8 3 2 IBM client of the Customer EJB The IBM client provides full access to the CustomerBean and shows the implementation of a self created valuetype CustomerKey The latter one is used in one of the finder methods of Cus tomerHome The example for the WebSphere Application Server C client is located in the directory OE_HOME corba client ibm2e jb 164 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The implementation of this example is based on the CORB
268. parseInt tempValues 2 System out print n StockDeliveryUpdateBean placing confirmation message on output queue putMessage OrderEntry JMS Qout null onMessage succeeded new stock level is iStockLevel System out print n StockDeliveryUpdateBean placing confirmation message on output queue end catch Exception oException System out print n StockDeliveryUpdateBean exception oException printStackTrace System out printIn StockDeliveryUpdateBean exception end System out print n StockDeliveryUpdateBean placing confirmation message on output queue try putMessage OrderEntry JMS Qout null onMessage failed catch Exception oException2 System out printIn StockDeliveryUpdateBean exception oException printStackTrace System out printIn StockDeliveryUpdateBean exception end System out print n StockDeliveryUpdateBean placing confirmation message on output queue end System out print n StockDeliveryUpdateBean onMessage end 5 We also add several utility methods The first of which is get nitialContext It is used to find the initial context for JNDI lookup of resources used by the bean These resources are the Stock entity bean and the Qout queue The method s listing is shown in Example 4 4 The method uses the resource bundle file to get information about the context factory JNDI server name and its port numbe
269. pecial itemsViewBean setCustomerSpecials custSpecials Testing the application To see the results of rule implementations test the application 1 In the WebSphere Administrative Console start OrderEntryServer if it is not already started 2 Bring up the application home page http localhost lt port_number gt OrderEntry index html 3 Select New Order 4 Type in the customer ID which is 0002 and click the Submit button The next page displays specials for the Gold level see Figure 3 15 40 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 1 90 day interest free financing 2 Appreciation gift with a purchase of over 50 Figure 3 15 Gold customer specials 5 Repeat the described steps for customer ID 0012 This customer has qualified for the Preferred level Preferred level specials are displayed as shown in Figure 3 16 1 60 day interest free financing 2 Appreciation gift with a purchase of over 75 Figure 3 16 Preferred customer specials 6 In the Rule Management Application change the specials offered to the customer initialization parameters for the Specials rules on the Implementation tab of the Properties window For example you can add a new special Free shipping with a purchase of over 100 for the Gold level a Start the Rule Management Application if it is not already started see 3 2 1 Setting up the development environment
270. plication and HTTP clients The server application components can access locale and time zone information through an object that implements the com ibm websphere il8n context Internationalization interface Caller context received by the server application components will be available to all server application components that are associated with the current thread of execution provided the Internationalization service is enabled on the containing application server Caller context may not be changed by the server application components Invocation context Invocation context is the context under which a component or business method executes On business method invocations it is the context that propagates from the invoking components to the corresponding server application components that implement these methods Invocation context may be accessed by using the com ibm websphere il8n context InvocationInternationalization interface of the Internationalization Service API Invocation context is managed according to the policies defined for the client and server application components gt Client side Internationalization CSI policy for the client application components gt Server side Internationalization SSI policy for the server application components In particular these polices specify API access restrictions how invocation context propagates on remote requests and the context under which a target request executes The server
271. ported ones and it still worked WebSphere Application Server to third party coexistence If a WebSphere Application Server to third party interoperation scenario is inadequate you can consider ORB coexistence as an alternative solution Coexistence is the ability of two different ORB runtime environments to reside and function in the same process This can cause problems because the CORBA interfaces were not designed to support this scenario Only newer ORB runtimes that use the Java ORB portability interfaces can coexist but even for them some incompatibilities are possible The advantage with coexistence is that the client interoperates with the server using the ORBs from the same vendor at all levels IIOP services and proprietary features Besides from the possible incompatibilities this scenario is standard CORBA business The ORB coexistence is a feature that has been available since WebSphere Application Server 3 5 Table 8 2 lists the client ORBs that can coexist with WebSphere Application Server 4 0 Table 8 2 Client ORBs that coexist with WebSphere Application Server 4 0 C a Windows NT Web 3 2 Java 3 4 Java Windows 2000 4 0 Java 4 1 Java AIX 4 3 Web 3 2 Java 3 4 Java 4 0 Java 4 1 Java 160 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide C Solaris 7 Web 3 2 Java 3 4 Java 4 0 Java 4 1 Java For further information see the WebSphere InfoCenter navigate to Enterprise services
272. pper cpp CustomerWrapper cpp 0E_HOME corba client vb2ejb Customer_merged_c hh 24 warning C4067 unexpected tokens following preprocessor directive expected a newline 0E_HOME corba client vb2ejb Customer_merged_c hh 27 warning C4067 unexpected tokens following preprocessor directive expected a newline Compiling the CustomerFactory class cl IF OE_HOME corba client vb2ejb 1 0E_HOME corba tools I MSVCDir include 1 VBROKERDIR include 1 VBROKERDIR include stubs DWIN32 D_USE NAMESPACE nologo MD GX c DORB_VisiBroker CustomerFactory cpp CustomerFactory cpp 0E_HOME corba client vb2ejb Customer_merged_c hh 24 warning C4067 unexpected tokens following preprocessor directive expected a newline 0E_HOME corba client vb2ejb Customer_merged_c hh 27 warning C4067 unexpected tokens following preprocessor directive expected a newline Note The usage of the flag DORB_VisiBroker causes in some files different implementations to be chosen for example in MyOrb cpp In these files it is checked with 1 fdef for ORB_WebSphere and ORB _VisiBroker 2 Link the tools library and DLL which produces the output Creating the tools lib lib NOLOGO LIBPATH 0E_HOME corba client vb2ejb LIBPATH 0E_HOME corba tools LIBPATH VBROKERDIR lib OUT tools lib def Trace obj Error obj Warning obj MyOrb obj CustomerWrapper obj CustomerFactory obj Creating library tools lib and object tools exp Linking the to
273. pplication server for the OrderEntry application There is a reason to create a new server instead of using the existing one If you created an application server before you installed WebSphere Application Server Enterprise Edition you won t see WebSphere Enterprise Services listed under the Custom tab for that application server You can add these services manually However creating a new application server is easier than adding WebSphere Enterprise Services manually Follow these steps to create a new application server 1 Run the Create Application Server wizard 2 Type the name of the server OrderEntryServer 3 Continue the wizard and click Finish in the last screen 4 5 Click the Custom tab Select OrderEntryServer in the Administrative Console You should see three WebSphere Enterprise Services as shown in Figure A 2 Appendix A Downloading and installing the OrderEntry application 225 F WebSphere Advanced Administrative Console Console View Tools Help ejo o v x a Ei WebSphere Administrative Dor a E Virtual Hosts oO Server Groups Installed Web Modules EE Nodes E O minsk E E Application Servers H 5 Defauit erven General Advanced File Transaction JvM Settings Services Custom Generic Servers G A Enterprise Applications Enabled Add H E minsk_sampleApp Automatic Generation of Plugin False H E Order Entry Application WorkArea Service True Edit E Resources In
274. prise Edition 4 0 A Programmer s Guide Storing the XJB JClassFactory in the Application Scope As a result of the one to one relationship between the JVM and the ActiveX process the fact that the JVM remains attached to the process throughout its life cycle means there is no need to call X JBInit more than once The resulting XJB JClassFactory object should be stored at the application scope Example 7 16 shows part of the SetupApplicationConfig method of an ASP application that uses Application oXJB and Application oCC to store the XJB and Client Container objects in application scope Note that an application lock is used to ensure that both objects are in the same thread Example 7 16 Code showing oXJB and oCC being stored in application scope Private Sub SetupApplicationConfig strUserid strPassword We are globalizing XJB and the Client Container object to speed things up Since you can only have one JVM and J2EE Client Container per process and also because we can t destroy the JVM it makes sense to keep these global and continue to reuse them Initialize the XJB Environment the JVM and Client Container Only Once Use an Application lock to ensure that both objects are jn the same thread Application Lock If IsEmpty Application oXJB Then AddMessage Initializing XJB JClassFactory Set Application oXJB XJBInit strWAS_HOME strJAVA_HOME strNAMING FACTORY End If If IsEmpty Application oCC
275. prise Edition Version 4 0 for more information about what publications are considered to be product documentation Comments welcome Your comments are important to us We want our IBM Redbooks to be as helpful as possible Send us your comments about this or other Redbooks in one of the following ways gt Use the online Contact us review redbook form found at ibm com redbooks gt Send your comments in an Internet note to redbook us ibm com gt Mail your comments to the address on page ii Preface Xi xii WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide WebSphere Application Server Enterprise Edition overview This chapter provides the high level overview of WebSphere Application Server Enterprise Edition v4 0 It describes the present position of WebSphere Application Server Enterprise Edition in the market The main interest here is the new part of the WebSphere Application Server Enterprise Edition called WebSphere Enterprise Services Copyright IBM Corp 2002 1 1 What is new in Version 4 0 WebSphere Application Server Enterprise Edition Version 4 0 is designed for the most e business demanding group of enterprises Its sophisticated software infrastructure enables the creation of a flexible distributed application It offers leading edge Web services and Java 2 Platform Enterprise Edition J2EE runtime environment The most significant changes in Version 4 0 include gt All three editions
276. private InvocationInternationalization invocationI18n try InitialContext jndi new InitialContext i18nService UserInternationalization jndi lookup java comp websphere UserInternationalization invocationI18N il8nService getInvocationInternationalization An exception indicates the service is disabled or could not be found catch Exception e e printStackTrace Set the invocation locale to en GB Locale localeToPropagate new Locale en GB invocationI18n setLocale localeToPropagate Set the invocation time zone to GMT SimpleTimeZone timeZoneToPropagate SimpleTimeZone Simp leTimeZone getTimeZone GMT invocation118n setTimeZone timeZoneToPropagate Call remote method 6 5 2 Tracing the Internationalization service function The trace service function can be enabled on the application server to emit trace statements regarding the Internationalization service function To enable the Internationalization service trace follow these steps 1 Start the application server you want to trace 2 In the WebSphere Advanced Administrative Console window expand WebSphere Administrative Domain gt Nodes gt node gt Application Servers gt application_server The properties related to the selected application server are displayed in the right hand pane Chapter 6 The Internationalization service 117 Note node represents the node on which the application server is located
277. put build_all Invalid argument Invalid argument Invalid argument There are no more files There are no more files There are no more files There are no more files Invalid argument Invalid argument javac Compiling 24 source files to F Henning oe corba server ejb2orbix testclt classes BUILD SUCCESSFUL The warnings can be ignored Running the test client You run the test client by executing two commands cd 0E_HOME corba server ejb2orbix start_testclient The test client produces no output But in the server window you would see the following output Waiting for requests com_ibm_itso_roch_credit_CreditInstituteImp isCreditableFor called pers struct Person forename xy lastname pay 9 75 com_ibm_itso_roch_credit_CreditInstituteImpl isCreditableFor returning _result false com_ibm_itso_roch_credit_CreditInstituteImp isCreditableFor called pers struct Person forename xy lastname pay 9 75 com_ibm_itso_roch_credit_CreditInstituteImpl isCreditableFor returning _result true Building the client stubs for the EJB To connect the OrderEntry application to the Creditlnstitute server the interface had to be compiled with the WebSphere Application Server IDL compiler To build the client stubs you have to execute two commands cd 0E_HOME corba server ejb2orbix nmake f makefile ejb2orbix ejb Chapter 8 The CORBA services 201 To delete all the generate
278. r Example 4 4 Method added to obtain the initial JNDI context private Context getInitialContext throws Exception ResourceBundle resources ResourceBundle getBundle OrderResourceBundle String JNDIcontextFactoryName resources getString factory String JNDIServerName resources getString system String JNDIServerport resources getString port Properties oProperties new Properties oProperties put Context INITIAL_CONTEXT_FACTORY JNDIcontextFactoryName oProperties put Context PROVIDER_URL iiop JNDIServerName JNDIServerport 70 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide InitialContext oInitialContext new InitialContext oProperties return oInitialContext 6 Add the next method called updateStockValue shown in Example 4 5 It increases the stock level of an item at a warehouse The updateStock Value method invokes the increaseStockQuantity method of the Stock bean in order to increase inventory Example 4 5 Method added to increase the stock level for an item at a given warehouse private int updateStockValue String warehouseld String itemId int newStockDelivered throws Exception Get the home interface Get references to EJB homes and the main EJB Context ctx getInitialContext find the Stock entity bean using the EJB reference java lang Object tempObject ctx lookup java comp env ejb Stock StockHome stockHome
279. r of the CustomerHome findByPrimaryKey method The creation of CustomerKey objects is done in two steps 1 Instantiate CustomerKey_ factory This is done in the constructor of the CustomerFactory class which uses CustomerKey CustomerFactory CustomerFactory const CosNaming NamingContext_ptr rootContext _customerHome NULL _keyFactory com ibm itso roch wasaejb CustomerKey_init VtIUtil getFactory const_cast lt char gt com ibm itso roch wasaejb CustomerKey CustomerKey RID 2 When the factory is created the CustomerKey objects are created by the create methods of the factory com ibm itso roch wasaejb CustomerKey_var ckey _keyFactory gt create__CORBA_WStringValue MyOrb toWStringValue key c_str 176 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 8 3 3 VisiBroker client of the Customer EJB The VisiBroker client provides partial access to CustomerBean It is more work to connect this client because WebSphere Application Server s valuetype library cannot be used and has to be created manually for the needs of the client The example for the VisiBroker C client is located in the OE_HOME corba client vb2ejb directory The implementation of this example is based on the ORBs interoperability sample called WebSphere EJB server to VisiBroker 4 1 C client which is shipped with WebSphere Application Server You find the description of all e
280. rKey object cl 1 0E_HOME corba tools I IC WAS_HOME Enterprise include I include DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE GX c nologo MD Od DSOM DLL_Customer com ibm itso roch wasaejb CustomerKey C cpp CustomerKey_C cpp Generating the CustomerKey valuetype object cl 1 0E_HOME corba tools I I WAS_HOME Enterprise include I include DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE GX c nologo MD Od DSOM DLL_Customer com ibm itso roch wasaejb CustomerKey_I cpp CustomerKey_I cpp x Generating the CustomerHome object cl 1 0E_HOME corba tools I I WAS_HOME Enterprise include I include DEXCL_IRTC DSHASTIFIED D_USE_NAMESPACE GX c nologo MD Od DSOM DLL_Customer com ibm itso roch wasaejb CustomerHome_C cpp CustomerHome_C cpp 2 Link the stub library and DLL This produces the following output Creating the Customer lib library 1ib nologo LIBPATH 0E_HOME corba tools LIBPATH LIBPATH WAS_HOME Enterprise lib LIBPATH lib OUT Customer lib def Customer_C obj CustomerKey_C obj CustomerKey_I obj CustomerHome_C obj Creating library Customer 1ib and object Customer exp Linking the Customer dll library link NOLOGO INCREMENTAL NO DEBUG LIBPATH 0E_HOME corba tools LIBPATH LIBPATH WAS_HOME Enterprise lib LIBPATH lib somororm 1ib somosalm lib Vtlib lib kernel32 1ib user32 1ib DLL Customer exp Customer_C obj CustomerKey_C obj CustomerKey_I obj CustomerHome_C obj OUT Customer d1
281. rderEntryWithRules ear uninstall the previously installed OrderEntry project in WebSphere Start WebSphere Administrative Console From the WebSphere Administrative Console start the Install Enterprise Application wizard Select the Install Application radio button Browse to OE_HOME Select OrderEntryWithRules ear Proceed through the wizard Click Finish On the Generate Code dialog click No op sa 9a0 9 Test the application Chapter 3 The Business Rule Beans service 31 ao Inthe WebSphere Administrative Console start OrderEntryServer Bring up the application home page http localhost lt port_number gt OrderEntry index htm Select New Order Type the customer ID 0007 and click the Submit button The next page displays customer level information Customer ID 0007 Name Jim J Fair Customer Level Platinum With the Rule Management Application you can change the amounts required to qualify for a certain customer level rule initialization parameters and see the changes reflected in the application without recompiling application code a Start the Rule Management Application if it is not already started see 3 2 1 Setting up the development environment on page 19 b Expand the Rule Namespace folder and select the CustomerRules folder c Right click the CustomerClassification rule and select Properties d e f Select the Implementation tab Select the initialization par
282. re 5 5 Edit WorkArea Service window There are some rules and special values for two parameters of the WorkArea service gt The maximum value for both settings is the maximum size of a Java integer type 2 Gb gt The smallest value is 1 byte which means that no requests associated with WorkArea can enter or leave the system Chapter 5 The WorkArea service 103 gt A value of 0 means there is no limit to the size of WorkArea that can be sent or received gt The default value is used if the value is specified improperly If you try to exceed the size limit of WorkArea WebSphere Application Server throws the org omg CORBA IMP_LIMIT exception during the request marshalling or unmarshalling 5 4 3 Passing WorkArea through multiple WebSphere Application Servers WorkArea can be started on a client and passed through multiple servers WorkAreas are only passed through servers that have the WorkArea service installed That means that WorkArea will not pass through an intermediary WebSphere Application Server Advanced server However WorkArea will pass through a WebSphere Application Server Enterprise Edition server that has disabled the WorkArea service 104 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The Internationalization service The Internationalization service provides a mechanism to propagate locale and time zone information from clients to servers and between server components This information
283. rea could not be terminated by OrderEntryServlet workArea getName e printStackTrace 5 3 Beyond the example The example application shows the simplest way to use WorkArea This section goes into more detail about other WorkArea features If the example has all the features you need you can safely skip this section 96 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 5 3 1 Using property modes to protect information There are two set methods for WorkArea The two argument method which was used in the example sets a default mode of normal for the property The three argument method takes a mode as the third argument This mode determines whether the property being set can be modified or removed by a remote method As stated in the previous section in order to change add or remove properties in WorkArea that was received from another servlet or bean a nested WorkArea must be created The properties in the original WorkArea cannot be changed The modes control what properties can be overridden in the nested WorkArea Normal mode is the default if no mode is specified when the property is set Normal mode means the property may be changed or removed Fixed mode means the property cannot be removed from WorkArea Read only mode means the value of the property cannot be changed Table 5 1 shows the result of operations performed on the properties depending on the mode that was set in WorkArea created b
284. ributed CICS typically used for COBOL applications or IBM Encina typically used for C and C applications TXSeries enables transaction distribution and coordination over a broad set of resource managers including relational databases IBM CICS 390 applications and traditional record oriented resources such as VSAM datasets all within a scalable reliable and secure context IBM MQSeries Messaging enables application integration by allowing business applications to exchange information across different platforms through sending and receiving data as messages MQSeries takes care of network interfaces assures once only delivery of messages deals with communications protocols dynamically distributes workload across available resources handles recovery after system problems and helps make programs portable Programmers can use their skills to handle key business requirements instead of wrestling with underlying network complexities gt WebSphere Application Server Enterprise Edition expands the capabilities of J2EE and Web services technologies along two important dimensions Enterprise class functions Enterprise class quality of service QoS gt The array of platforms where WebSphere Application Server is available includes Windows NT 2000 AIX and Sun Solaris As with previous releases of WebSphere Application Server Enterprise Edition the new version offers a much broader range of functions compared to
285. roducts of other vendors and the implementation of many basic valuetypes for Java serializables see 8 2 3 C CORBA software development kit SDK on page 162 8 2 1 WebSphere Application Server support scenarios If the CORBA specifications were complete unambiguous and the vendors had the correct implementations of the same level of the specification then interoperability would no longer be aconcern However as already mentioned this is not the case As a result we need to consider several different scenarios that can be divided into three groups gt WebSphere Application Server to WebSphere Application Server gt WebSphere Application Server to third party CORBA interoperation gt WebSphere Application Server to third party coexistence WebSphere Application Server to WebSphere Application Server Only WebSphere Application Server components are involved so that they are normal J2EE and CORBA business The following scenarios are possible gt WebSphere Application Server C CORBA client to a WebSphere Application Server EJB server gt WebSphere Application Server C CORBA client to a WebSphere Application Server C CORBA server gt WebSphere Application Server EJB server as a CORBA client to a WebSphere Application Server C CORBA server WebSphere Application Server to third party CORBA interoperation WebSphere Application Server interacts with a third party CORBA ORB You have to consider the followi
286. rs received before 2 00 PM will be processed by 5 00 PM the same day The times given of course are in the time zone of the server that is processing the order It is important to know the client s time zone in order to give customers in other time zones the correct times for same day processing Other time zone sensitive operations include time stamping messages order tracking transaction completion time and estimated shipment arrival times 6 1 3 The Internationalization service solution The WebSphere Enterprise Internationalization service solves the locale and time zone mismatch problems without the traditional limitations The locale list and time zone are managed as a unit referred to as an internationalization context The Internationalization service manages the distribution of internationalization context across the various components of Enterprise JavaBean applications including Java client applications Enterprise JavaBeans JSPs and servlets Server side components can use the internationalization context API to access distributed internationalization context and then localize computations according to the locale or time zone of client side components 106 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The service associates an internationalization context with each thread of execution in an application When a client side program invokes a remote business method the Internationalization service o
287. rshals request with parameters and demarshals the reply with results A server ORB is responsible for handling the object request from a client by demarshalling a request invoking the appropriate method on the service object and marshalling the reply results Low level communication between different object spaces ORBs is done by using the Internet Inter ORB Protocol IIOP When a client invokes a member function on a CORBA object the ORB intercepts the function call The ORB redirects the function call across the network to the target object After the target object has created the response the ORB then collects the result from the function call and return this to the client Figure 8 1 shows the role of CORBA for distributed communication OmniOrb Orbix Lisp Java Linux Win95 AMD Intel Component VisiBroker Broker Cobol C Win2000 AIX Motorola PowerPC Figure 8 1 Role of CORBA communication CORBA has been implemented by several vendors The most wide spread implementations are Orbix from IONA VisiBroker from Borland ComponentBroker from IBM OmniOrb from AT amp T available as open source YYY Yy 154 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Note In practice the interoperability between ORBs of different vendors has been poor for some time because the first releases of CORBA did
288. ructure services as they are and click Next oN Oa aA Activate the check box for the Naming Service Click Next 9 Select the Start all services via a startup script radio button 10 Click Finish 11 Click Deploy After successful deployment you see a display like the example in Figure 8 11 It tells you about scripts to be used for setting up the environment in a shell and for starting and stopping your services Orbi 2000 Configure x 10 x Congratulations Your configuration successfully deployed To set your environment to use this configuration domain run the following C Program FilesiionatetcibimOrderEntry_env bat To start or stop the services associated with this domain run the following IONA Orbix 2000 C Program Filestionatetcibinstart_OrderEntry_services bat Configuration CAProgram Filestiona etcibinistop_OrderEntry_services bat Figure 8 11 Orbix configuration scripts Chapter 8 The CORBA services 189 To use the created configuration batch files you have to add the directory lt orbix_home gt etc bin to the PATH environment variable There are not many visual tools around with the Orbix installation so you basically use the command prompt To setup all environment variables properly you would call OrderEntry_env bat In addition to these scripts there is a command line administration tool called itadmin This tool is described in Chapter 16 Managing Orbix Se
289. running the server and the test client you have to start a command prompt and execute 0E_HOME corba server ejb2orbix set_ejb2orbix_env bat OrderResourceBundle properties in the OrderEntry ear file has to be edited as well You have to set the following property replace OE_HOME with the real path value nameservice ior directory 0E_HOME corba server ejb2orbix Before you can start the server you have to start Orbix services locator service node daemon and naming service by entering start_OrderEntry_services 190 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Building tools Beside from the common build tools like nmake C compiler and so on we use two other tools ant and Orbix genies Ant Ant is like Tomcat a subproject of the Jakarta project from the Apache Software Foundation Ant is a Java based build tool that uses XML files as input It is a more general form of make The Ant home page is at http jakarta apache org ant index htm You can find the Ant user manual at http jakarta apache org ant manual index htm Orbix genies Orbix 2000 has a feature called code generation toolkit It is for the generation of a complete working client and server directly from your IDL interfaces The two basic components are the generator itself idlgen and several input TCL scripts called genies You get the available genies with the following call idlgen list It produces the output
290. rver Pages Each thread that is created in the ActiveX process will be mirrored in the Java environment when the thread communicates through the ActiveX to EJB bridge In addition once all references to Java objects there are no JObjectProxy or JClassProxy objects in an ActiveX thread are released the ActiveX to EJB bridge detaches the corresponding thread from the JVM Therefore you must be careful that any Java code that you access from a multi threaded Windows application is thread safe Visual Basic and Chapter 7 The ActiveX bridge service 141 VBScript applications are essentially single threaded Therefore Visual Basic and VBScript applications don t really need to worry about threading issues in the Java programs they access With Active Server Pages you need to make sure that your Java program is thread safe 7 6 Error handling All exceptions thrown by Java are encapsulated and re thrown as COM errors and appear as Err objects in Visual Basic and VBScript Java exceptions are more complex than Visual Basic Err objects which only contain error number and description fields The details of the Java exception are written to the two Err fields in Table 7 3 Table 7 3 Correlation between COM errors and Java exceptions Error number Hex Error number decimal Description representation ox6002 o pease Initialization error Initialization error C ooo Java exception Error description is the Java Stack Trace ox6FFF 286
291. rvices with itadmin in IONA Orbix 2000 Administrator s Guide C Edition On Windows NT and 2000 you have the possibility to register your domain s Orbix services as Windows services so that you can start the services via the services panel How this is done is described in Appendix A Orbix Windows NT Services of IONA Orbix 2000 Administrator s Guide C Edition Note Several files are created during the Orbix 2000 configuration process These files are called from the batch files supplied in the OrderEntry zip file See the last window in the configuration wizard as shown in Figure 8 11 for the exact location of the generated files 8 4 2 Connecting to an Orbix server The following sections discuss what we had to do to create an Orbix server and connect the OrderEntry application to this server We go through the basic steps which are discussed in the following sections Set up the environment Build tools Define the IDL Build the server Run the server Build the test client Run the test client Build the client stubs for the EJB Run the EJB client CONDAAWN gt You can find details about C and Java programming with Orbix 2000 V2 0 at the following sites gt http www iona com docs orbix2000 2 0 pguide_cpp html index html gt http www iona com docs orbix2000 2 0 pguide_java html index htm Setting up the environment To set up the necessary environment variables for the build steps and for
292. ry Trace specification Out all disabled ORBRas all enabled Trace output file Trace outputfile Standard error C Standard output Specify orb_defaultserverlog ok _ canei Helo Figure 8 10 Filter and file settings for the CORBA traces Note IBM Distributed Debugger can be used as an additional problem determination tool It enables source level debugging for both C and Java code 8 4 Connecting OrderEntry application to C CORBA server This section covers the opposite direction of interoperating with an EJB In this scenario the OrderEntry application is in the role of the client and not of the server Chapter 8 The CORBA services 187 We connect to a C server that offers the interface CreditInstitute This interface can check the creditability of an OrderEntry customer We only cover Orbix for the server implementation 8 4 1 Configuring the environment We used the following environment for our sample server Windows 2000 SP 1 WebSphere Application Server V4 0 1 Enterprise Edition Microsoft Visual C 6 0 Orbix 2000 Enterprise Edition v2 0 Developers Kit for C and Java vvvy The installation and configuration of Windows WebSphere Application Server and Microsoft Visual C are not covered in this redbook These are explained in the product specific installation guides Prerequisites This scenario requires the following general prerequisites 1 Extract the ZIP file c
293. ry and variant An application can use Locale to properly format messages or sort string lists for example by passing it to locale sensitive methods of other SDK objects such as java text NumberFormat java text DateFormat or java text Collator gt TimeZone TimeZone represents a time zone offset from GMT An application can use TimeZone to perform time sensitive computations For example the constructors of java util Calendar accept a TimeZone parameter that configures the resultant Calendar objects to compute time according to the supplied time zone and daylight savings rules Refer to the Java SDK API documentation for a complete description of each type and the methods available Note The Internationalization service currently only supports the java util SimpleTimeZone time zone type Unsupported time zone types are replaced with the default SimpleTimeZone of the JVM when supplied to service API methods 6 2 2 Types of context There are two types of context gt Caller context gt Invocation context Both consist of an ordered locale list and a time zone Chapter 6 The Internationalization service 107 Caller context Caller context is the Internationalization context that server application components EJBs servlets JSPs receive on incoming requests originating from any J2EE application component Note that such requests may immediately originate from the server components such as EJBs and servlets as well as J2EE ap
294. s Active Server Pages To enable your ActiveX process to use the ActiveX bridge functionality the WebSphere Application Client supplied with WebSphere Application Server Advanced Edition must be installed on the client The ActiveX bridge enterprise service is then installed on top of the application client Now when the client creates a JVM it will have access to the ActiveX bridge functionality 7 1 1 Supported languages and platforms ActiveX programs can be written in Visual Basic VB VBScript ASP Delphi PowerBuilder and other COM supporting languages Although the ActiveX to EJB bridge should work from any automation component the only formally supported languages are Visual Basic VBScript and ASP All the examples in this chapter will deal with Visual Basic and ASP An issue with being unable to invoke case sensitive Java methods prevents an easy implementation of a PowerBuilder solution See 7 5 4 Invoking Java methods on page 137 The ActiveX bridge is supported on both Windows 2000 and Windows NT Chapter 7 The ActiveX bridge service 123 7 2 The Visual Basic OrderEntry client application Before digging into the details of the actual code let s look at the application design issues 7 2 1 Designing an ActiveX client program 124 A good software design promotes component reusability and its independence from other components in the system Many designs exist today but one of them has emerged as the de fac
295. s expected to be found Accept First Only the first rule found by the framework will be fired Accept Last Only the last rule found by the framework will be fired Firing strategy The firing strategy is responsible for invoking the BRBeans rules returned by the filtering strategy The framework provides one firing strategy because all rules are fired the same way Combining strategy Implementations of the combining strategy provide different ways to handle BRBeans rule results Return All The results of all fired rules are returned default Return First The result of the first fired rule is returned Return Last The result of the last fired rule is returned Return AND Returns the logical AND of the fired rule results All fired rules must return ConstraintReturn or Boolean objects Return OR Returns the logical OR of the results from the fired rules All fired rules must return ConstraintReturn or Boolean objects Throw Violation Returns a true ConstraintReturn object if all fired rules are successful and throws ConstraintViolationException if some of the fired rules fail As in the finding strategy the result of the BRBeans rule with the highest precedence is considered to be the first result Note Developers can create custom strategies if the predefined BRBeans strategies do not provide the functionality required by the application For more information on creating custom strategies see the
296. s though the original property was changed Whether the set succeeds depends on the property mode set in the original WorkArea A property can also be removed from a nested WorkArea Whether the property can be removed depends on the property mode set in the original WorkArea Here again the property is not removed from the original WorkArea but is masked by the new WorkArea so that it appears to have been removed When control returns to the calling method that created the original WorkArea the property is restored with its original value Example 5 8 shows how we would remove the item quantity from WorkArea Example 5 8 Removing a property from WorkArea import com ibm websphere workarea Context ctx getInitialContext UserWorkArea workArea getWorkArea ctx workArea remove quantity None of the changes made in a remote method that creates a nested WorkArea are propagated back to the caller Properties removed in the nested WorkArea are still available to the calling method All properties will have the same values that were set by the calling method Terminating a nested WorkArea When finished with a nested WorkArea call the complete method just as for the original WorkArea This terminates only the nested WorkArea Recall that the original or nested WorkArea may only be terminated by the servlet or bean that created it 100 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 5 3 3 Cha
297. s thrown 5 4 Configuring the WorkArea service in WebSphere Application Server The OrderEntryServer configuration includes the necessary setup for the WorkArea service There are very few settings to adjust 5 4 1 Ensuring the WorkArea service is enabled in the Administrative Console The WorkArea service is enabled by default To make sure it has not been disabled start the Administrative Console and select the server from the Application Servers folder From the Properties window select the Custom tab WorkArea Service should be listed in the window as shown in Figure 5 4 102 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide General Advanced File Transaction JVM Settings Services Custom Service Enabled Automatic Generation of Plugin WorkArea Service False Figure 5 4 Administrative Console server properties window 5 4 2 Setting maximum send and receive size The maximum size of WorkArea that can be sent from or received by the server can be set in the Administrative Console From the Custom tab Figure 5 4 select WorkArea Service and click the Edit button From the pop up window select the Custom tab This window has two values on it as shown in Figure 5 5 The default is 10000 bytes for both values gi Edit Custom ServiceWorkArea Service ee i xi General Custom Properties Add Remove OK Cancel Help Figu
298. s to initialize the ORB Example 8 10 shows the code fragments Example 8 10 Initializing the Orbix ORB CORBA ORB_var global_orb CORBA ORB _nil CORBA Object_var tmp_ref For temporary object references cout lt lt Initializing the ORB lt lt endl global_orb CORBA 0RB_init argc argv Creating a portable object adapter POA The object adapter is the link between the ORB and the servants implementation objects of the interfaces The POA provides the server side runtime support that connects server application code to the networking layer of the ORB Example 8 11 shows how a POA is created Example 8 11 Creating a POA PortableServer POA_ptr create_simple_poa const char poa_name PortableServer POA_ptr parent_poa PortableServer POAManager_ptr poa_manager Create a policy list Policies not set in the list get default values CORBA PolicyList policies policies length 1 int i 0 Make the POA single threaded policies it parent_poa gt create_thread_policy PortableServer SINGLE_THREAD MODEL assert i 1 return parent_poa gt create_POA poa_name poa_manager policies tmp_ref global_orb gt resolve_initial_references RootPOA PortableServer POA_var root_poa PortableServer POA narrow tmp_ref assert CORBA is_nil root_poa PortableServer POAManager_var root_poa_manager root_poa gt the_POAManager assert CORBA is_nil root_poa_m
299. s used for primitive COM types and vbSet for objects In VBScript use Eval myApp create 123 The Cal1ByName function doesn t handle Java exceptions in the standard way see 7 6 Error handling on page 142 Instead it throws errors with Err Number of 438 and the Err Description field that doesn t contain the Java exception stack trace This means that any valid exceptions have to be caught and handled in the Java code or an error code has to be returned as the return value from the method Passing Object type parameters The ActiveX bridge uses the object type of the arguments passed to a method to find the method on the Java object or class that is intended to be invoked Because of polymorphism sometimes the type of the parameter passed doesn t match the parameter in the method signature For example a method specifies its parameter type as java lang Object If you try to invoke such a method passing a parameter of other type which inherits from java lang Object a COM error with the description object does not support this property or method is thrown To cater to this the ActiveX bridge API provides a container for such parameters The container XJB JMethodArgs is retrieved using the GetArgsContainer method on the JClassFactory object Each parameter can be added to the JMethodArgs object by using the AddObject method The first parameter of this method is the type declared in the target method s si
300. service is a framework for externalizing implementation of business rules The framework eliminates the need to redeploy application code after changing business logic This is done by decoupling business rules implementation from the application code that uses them The following terms are used throughout this chapter vvvvvy Business rule A description of a business process or practice Business logic A part of program code that implements a business rule BRBeans rule A business rule implemented in the BRBeans framework Rule client Application code that uses a BRBeans rule Rule implementor A Java class that implements a business rule Trigger point A place in the rule client where a call to fire a BRBeans rule is made 3 1 1 Benefits The main benefits of BRBeans include gt Isolation of volatile business logic from application code Business logic and application code are implemented in different compilation units The rule client can be implemented in Java classes servlets or Enterprise JavaBeans EJBs Business rules must be implemented as Java classes The rule client knows the BRBeans rule name and interface but it is not aware of the rule implementation Keeping knowledge of business rules external to the application Variable business rule data is not embedded in the rule client and can be easily accessed with the Rule Management Application Administrative maintenance of business logic Application behavior
301. sible for error handling in the onMessage method Returning the exception to the container would cause the message to be reprocessed If the problem would persist the exception would again be returned The message could be placed on another queue of unprocessed messages The message could later be inspected by a system administrator or processed by another message bean Since the onMessage is not part of a transaction the results of partially processed messages may persist depending upon the application public void onMessage javax jms Message msg try call to business logic catch java lang Throwable exception put message on unprocessed queue unprocessedQueue put msg Putting the message to another queue can also be used for a message that is part of a global transaction This prevents the listener from stopping and permits it to continue processing messages This is especially desirable behavior for handling application exceptions when messages for example are not formatted as expected There is an alternative implementation for exception handling It is similar to the previous example That is the transaction configuration is the same and the message bean is not part of a global transaction public void onMessage javax jms Message msg try call to business logic catch java lang Throwable exception Potentially the message bean may need compensation logic to undo things that
302. solved it is necessary for the associated EJB jar to be stopped and restarted using the WebSphere Application Server Administrative Console to continue handling messages from the destination When the message that removed from the destination is part of a global transaction any exception in the onMessage method has the effect of marking the transaction as rollback only The transaction rolls back causing any work performed on the global transaction to rollback which includes leaving the message on the queue 86 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The basic structure of the onMessage method should follow one of the following forms gt Message bean is part of a global transaction The exception is caught in the onMessage method The transaction is marked as rollback only This causes the transaction to be rolled back at commit time The message is placed back on the queue and processed again until either the transaction successfully commits or the maximum number of retries is reached At this time the listener is stopped No additional messages are processed until the problem is fixed public void onMessage javax jms Message msg try call to business logic catch java lang Throwable exception Mark the transaction as rollback only tx setRollbackOnly gt Message bean is not part of a global transaction Since there is no transaction active the application is respon
303. ssion oQueueConnection createQueueSession false Session AUTO_ ACKNOWLEDGE Obtain the Destination object from JNDI System out printIn StockDeliveryUpdateBean find Queue Queue ioQueue Queue oInitialContext ookup TargetQueueJNDIName System out printIn StockDeliveryUpdateBean find Queue end Create a QueueSender System out printIn StockDeliveryUpdateBean creating queue sender oQueueSender oQueueSession createSender ioQueue System out printIn StockDeliveryUpdateBean creating queue sender end Create a message to send to the queue 72 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide TextMessage message oQueueSession createTextMessage text Set CorrelationID if msgID null message setJMSCorrelationID msgID and send it System out printIn StockDeliveryUpdateBean sending message to queue oQueueSender send message System out printIn StockDeliveryUpdateBean sending message to queue end Close the connection close calls will cascade to other objects oQueueSender close oQueueSession close oQueueConnection close oQueueConnection null System out printIn StockDeliveryUpdateBean request to put message text end catch JMSException je System out printIn putMessage failed with t je Exception
304. stand about WorkArea is the scope WorkArea is associated with a thread Information is passed in WorkArea from the caller to a remote method which is done using one way communication The remote method is not allowed to change add or remove properties in WorkArea created by the caller Attempting to use the set method on WorkArea that was not created by the current component results in a com ibm websphere workarea NotOriginator exception To add a new property or override the properties in an existing WorkArea that was initiated in another method the remote method must create a new WorkArea that is associated with the existing one A new WorkArea is called nested WorkArea Creating and using a nested WorkArea is described in more detail in 5 3 2 Nested WorkAreas on page 97 WorkArea may be created by a client and then passed transparently to a server or it may be created by the server and passed transparently between serviets and EJBs on the same or different servers In any case WorkArea behaves in the same way We refer to method calls as remote even though for the example application the calls are actually made on the same server The only time WorkArea can be considered to be passed locally is when the servlet or bean makes a call to a local helper class that is not a servlet or EJB WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide WorkArea is associated with a single thread of execution WorkArea is
305. stclt TestPackage client java java_poa_genie tcl creating testclt TestPackage com ibm itso roch credit CreditInstitutelImp java java_poa_genie tcl creating testclt TestPackage server java java_poa_genie tcl creating testclt build xml Type ant to compile the generated code Note If you are experiencing problems check if your CLASSPATH environment variable name is defined all in uppercase That is the way the TCL script expects it to be set For Windows it doesn t make a difference but for genie it does Modifying the generated test client source You can compile and run the generated sources without any changes We only changed the name of the server entry in the namespace The makefile copies over the one edited file The output is Copy over the completed test client files copy y testclt_completed client java testclt TestPackage 1 file s copied Compiling the test client code idlgen creates the ant type build file build xml This file is used for the compilation of the test client code The steps for compiling test client code are 1 The IDL compilation produces the following output Compiling the test client sources cd testclt ant buildfile build xml Buildfile build xml 200 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide init mkdir Created dir F Henning oe corba server ejb2Zorbix testclt classes id _compile 2 From the Java compile you get the following out
306. stitute objects The CreditInstitute object is the C interface class that is derived from the IDL description like the InformationConfidential and PersonNotFound exception classes The implementation for CreditInstitute interface is done by CreditInstitute Imp It is derived from the Orbix specific class IT_Servant_BaseOverrides which itself is derived from the general CORBA class ServantBase The CreditInstitute Imp class uses two more generated helper classes IT GenieRandom and IT _GeniePrint The first is one for generating random answers and the second one is for printing trace information Figure 8 12 shows the class diagram for these classes Servant a POA_ Base Manager IT_Servant Credit BaseOverrides Institute C Eo IT_Genie Information Random Confidential Creditinstitute _Impl IT_Genie PersonNot Print Found Figure 8 12 Class diagram for ejb2orbix You can divide the classes into three groups gt CORBA or Orbix base classes POA Manager POA ServantBase IT_ServantBaseOverrides gt IDL generated classes CreditInstitute InformationConfidential PersonNotFound IT_GenieRandom IT_GeniePrint gt Manually created classes main CreditInstitute_Imp Chapter 8 The CORBA services 195 Initializing the Orbix ORB The first step i
307. stored BootstrapPort nnnn The port of the listener on the WebSphere server jar xxxx The name of the jar within the ear file that contains the Java Client if you have more than one Java Client Jar in the same EAR file the path is relative to the root of the EAR file XJBPutProperty oXJB oProps initonly true If Trim strBootstrapHost lt gt Then XJBPutProperty oXJB oProps BootstrapHost strBootstrapHost End If If IsNumeric strBootstrapPort Then XJBPutProperty oXJB oProps BootstrapPort strBootstrapPort 1 1 1 1 132 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide End If If Trim strAppClientJar lt gt Then XJBPutProperty oXJB oProps jar strAppClientJar End If If we want to turn tracing on we can do something like this XJBPutProperty oXJB oProps trace com ibm ws client applicationclient ApplicationClientMetaData debug enabled XJBPutProperty oXJB oProps tracefile c xjb log DoEvents Launch the client container In the java world it would start the Java Application within the container Here however we ARE the application so we avoid starting it by setting the property initonly true above The Client Container overrides the Java Namespace so that we can load the appropriate EJB class files from within our supplied ear file oCC launch strEARFile oProps astrAppParams Set XJBGetJ2EEClientContainer oCC Set oCC
308. t 0 000 107 6 2 2 Types Of COMOX ssc ceric le a ed feo a oe Ses ate cc Bast oe heb Sob 107 6 2 3 The Internationalization Service API nauna aaua aaea 108 6 2 4 Internationalization context management 0 20 e eee eee 111 6 3 Using the Internationalization service in the example application 112 6 3 1 Binding to the Internationalization service 0 0 00 e eee eee 112 6 3 2 Retrieving and using the caller internationalization context 113 6 3 3 Retrieving and using the invocation internationalization context 114 6 4 Enabling or disabling the Internationalization service 200 114 6 4 1 Enabling internationalization context for an application server 114 6 4 2 Enabling internationalization context within EJB Java application clients 116 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 6 4 3 Configuring the programming environment 0000e ce eee eee 116 6 5 Beyond the example application 1 0 2 0 00 eee 116 6 5 1 Setting invocation locale and time zone 00200 cece eee ee 117 6 5 2 Tracing the Internationalization service function 00005 117 Chapter 7 The ActiveX bridge service 0 c eee ee 121 TA INtrOMUCHION oa eto ae ie fee Yond DM ies Grae eat ed nadia cea 122 7 1 1 Supported languages and platforms aaau eee 123 7 2
309. t container 131 modifying EAR file for ActiveX J2EE client container 148 no client container approach 129 optimized container approach 131 optimizing the EAR file 151 using J2EE client container 129 ActiveX client application components 127 installing 126 ActiveX client program design 124 ActiveX program accessing aJavaclass 136 accessing Java objects 136 Active Server Page guidelines 145 case sensitivity 137 client container guidelines 147 error handling 142 good programming guidelines 144 handling arrays 140 invoking Java methods 137 passing Object type parameters 138 primitive data type conversions 133 return value 139 thread 141 Visual Basic guidelines 144 ActiveX_Config 127 ActiveX_EJBHomeRef 127 ActiveX_XJBHelpers 127 Activity context 215 activity wrapper process 214 Ant 191 Application Assembly Tool AAT 131 149 Application Builder for Components ABC 210 arrays 140 automation container 140 Copyright IBM Corp 2002 B base rule 18 32 33 38 bean managed transaction BMT 85 Bind 172 185 BMT bean managed transaction 85 bootstrapping 182 BPBeans 4 209 activity 212 Activity context 215 activity wrapper process 214 Application Builder for Components ABC 210 basics 210 compensation mechanism 210 compensation pair process 214 concurrent process 214 context 215 development 216 extended business transactions 210 framework 210 InOut Port 213 Input Port 213 instance cluster process 214 JavaBean co
310. t 155 Server Session Thread Pool 86 server centric placement 125 Server side Internationalization SSI policy 108 111 setupCmdLineXJB 126 Shared WorkArea 3 source cluster process 214 SSI Server side Internationalization policy 108 111 Stock Table Layout Stock 13 strategy object 24 stub 156 167 179 201 swap process 214 T TCL 191 200 thread 141 time limit process 214 topic 53 topic connection factory 80 traces 186 206 transaction support 84 transactional queue connection factory 59 trigger point 16 22 24 Trigger Point framework 38 trigger point strategy 37 TriggerPoint 16 30 TXSeries 2 U unavailable rule state 25 Unit of Work UOW Director 214 Userlnternationalization interface 108 109 UserWorkArea 101 UserWorkArea interface 101 V valuetype 158 174 176 valuetype library 162 variant 140 VBScript 123 View 124 VisiBroker 163 177 186 Visual Basic 122 123 Visual C 122 WwW WebSphere Application Server 60 80 159 Advanced Edition 2 Enterprise Edition 2 passing WorkArea through multiple servers 104 WorkArea configuration 102 WebSphere Application Server Advanced Edition 2 WebSphere Application Server Enterprise Edition 2 WebSphere Enterprise Services 1 2 3 WebSphere messaging 89 WebSphere Studio Application Developer 14 18 68 WorkArea 92 accessing 95 binding to facility 93 changing the mode 101 completing 96 configuring 102 configuring in WebSphere Application Server
311. t the lifetime of the application either as a global variable or by passing the reference as a method parameter There is also a performance impact of calling createObject XJB ClassFactory and re running the code more than once to create and initialize the XJB ClassFactory object In the VB OrderEntry Client Application the XJB ClassFactory object is stored in the g_ Config object which is stored globally All references are made using g Config XJB By doing this g Config can ensure the JVM has been initialized before it is returned Re initializing the JVM If changes are made to the JVM initialization parameters Visual Basic or the ActiveX process has to be restarted in order to bring those changes into effect If Visual Basic is not restarted the XJBInit function just returns the original JVM 144 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 7 7 2 Active Server Pages guidelines To optimize the usage of the ActiveX bridge with the ActiveX programs use the guidelines in the following sections Unloading the ASP application If the JVM needs to be re initialized due to changes in the client side EAR file or JVM initialization parameters the ASP application has to be restarted This is done by using the Unload button in the Internet Information Server administration console in the ASP application properties Figure 7 5 and Figure 7 6 OrderEntry_ASP Properties a 2 x Virtual Direc
312. t the life of the application The only instance of this class is created when the application is launched It is public so other classes can reference XJB JClassFactory and therefore the JVM by calling g Config XJB The JVM and CC are initialized when g_ Config is first called This happens just after the main window is displayed gt Holds the reference to the initialized Act iveX_EJBHomeRef object This object is first initialized when g_Config EJBHomeRef is first called This happens just after the main window is displayed Chapter 7 The ActiveX bridge service 127 gt In this example it stores configuration parameters such as the naming factory class and the server address and port number that are obtained from the options window It also stores all the parameters that the application needs to initialize and extract the client EAR file COrderClerk This class provides the main functionality for the client It holds the Order Entry Clerk EJB reference and uses it to retrieve a list of customers and items when the user selects a search button It also uses Customer and Item EJB home interfaces retrieved from the ActiveX_EJBHomeRef module to invoke the findByPrimaryKey method if the user chooses to make a selection by directly entering the customer or item ID Other class modules The other classes are used to represent the business objects in this application like customers or items The following section discusses the steps necessary
313. tDateTimeInstance DateFormat FULL DateFormat FULL locale return df format date Retrieving and using the invocation context is similar to retrieving and using the caller context The main difference is that the invocation context may be set and changed by the client while the caller context is set by the Internationalization service and may not be changed 6 4 Enabling or disabling the Internationalization service In order to use the Internationalization service it must be first enabled on WebSphere Application Server Enterprise Edition If the client is an EJB Java application client the service must also be enabled on the client HTTP browser clients do not require enabling of internationalization this support is provided by the browser 6 4 1 Enabling internationalization context for an application server Any Enterprise JavaBean JSP or servlet can use the internationalization context once the Internationalization service is enabled on the application server The Internationalization service is enabled within application servers using the Custom tab The Custom tab lists all Enterprise Services available to a particular application server and provides access to the configuration properties of each Perform the following steps to enable internationalization context within an application server 114 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide 1 In the WebSphere Advanced Administrative Console wi
314. te Ms 11101 12 01 AM Midiy h mm a End date Midiyy h mm a Example Date 10 23 01 1 45 PM Classification Rule is not classified and does not perform a classification Rule performs a classification Rule is classified with the following classification Status M Rule is available for use Rule is in effect Cancel Help Figure 3 7 General properties of the CustomerClassification rule g Click the Implementation tab h Click the Add button next to the initialization parameters list and add three parameters e Amount to qualify for the Preferred Club Type Integer Value 1000 e Amount to qualify for the Gold Club Type Integer Value 2000 e Amount to qualify for the Platinum Club Type Integer Value 3000 i Select the Local firing location see Figure 3 8 Chapter 3 The Business Rule Beans service 29 _ New Rule General le mentation Description Dependent Rules Other Java rule implementor rules CustomerClassification z Firing location Local z rlnitialization parameters Add Description Amount to qualify for Preferr Constant value 1000 of type Integ Change Amount to qualify for Gold C Constant value 2000 of type Intege Amount to qualify for Platinu Constant value 3000 of type Intege Delete AIRE raul Fiting parameters Pass firing parameters from trigger point unchanged
315. ternationalization Service True EEA JDBC Providers Extended Messaging SupportSe True Remove 3 Sample DB Driver Data Sources OrderEntryJDBC Data Sources JavaMail Sessions Figure A 2 Verifying the application server 6 If you plan to use the WebSphere Application Server internal HTTP server you need to add an HTTP port information to the default_host virtual server Note Port information can be found by performing the following steps 1 Select the Services tab on the OrderEntryServer configuration pane 2 Select Web Container Service and click Edit Properties Click the Transport tab to locate the HTTP port number Installing the OrderEntry application The OrderEntry application relies on some platform installation dependant data This data is used by the application through the object of type java util ResourceBundle This ResourceBundle object is created at runtime based on two files supplied with the OrderEntry EAR file You have to modify these two files according to your environment Both of them have the same name OrderResourceBundle properties but are located in two different JAR files within OrderEntry ear Deployed OrderEntryEJB jar and OrderEntryWeb war use WinZip or a similar utility to open the EAR and JAR files The listing of the file contained within Deployed_OrderEntryEJB jar is shown here factory com ibm websphere naming WsnInitialContextFactory system localhost port
316. ternationalization getCallerInternationalization Returns an object implementing the Internationalization interface This interface allows read only access to the caller context If the service is disabled the method throws a java lang I1 legalStateException exception gt InvocationInternationalization getInvocationInternationalization Returns an object implementing the InvocationInternationalization interface This interface allows read and write access to the invocation context according to the internationalization context management policies In the current release only an application client may change the invocation context If the service is disabled the method throws a java lang I1legalStateException exception The Internationalization interface The Internationalization interface allows read only access to the internationalization context Use this interface to access the caller context within server side application components Example 6 2 shows the Internationalization interface Example 6 2 The Internationalization interface public interface Internationalization public java util Locale getLocales public java util Locale getLocale public java util TimeZone getTimeZone The Internationalization interface provides three methods for read only access to the internationalization context elements gt java util Locale getLocales Returns the array of locales associated with the current thread If the
317. the CreditInstititute object itadmin ns resolve OrderEntry CreditInstitute Enabling CORBA traces Orbix 2000 has a logging subsystem You get different levels of logging reports for example warning information and so on that can be filtered and redirected to files Also useful problem determination could be accomplished by enabling the tracing for WebSphere EJB Java client 206 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The logging output is separated based on the configuration domain For the OrderEntry domain you get several files written to the lt orbix_home gt var OrderEntry logs directory The default settings include logging for the locator naming and the node daemon service You can edit the logging properties for the OrderEntry domain in the file lt orbix_home gt etc domains OrderEntry cfg You can find more details about the Orbix 2000 logging subsystem in ONA Orbix 2000 Administrator s Guide C Edition in Chapter 14 Managing Orbix Logging at http www iona com docs orbix2000 2 0 admin_cpp htm1 index html Chapter 8 The CORBA services 207 208 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The Business Process Beans service This chapter discusses the Business Process Beans BPBeans service including some technical details about the service Since the BPBeans service is a technical preview and have several limitations we do not use the
318. the Model before its effects become visible in the View This rule guarantees that a state change updates all Views and the Views remain synchronized Often implementations with a single Controller violate this rule because of a lack of thought I already know that this state change will occur and therefore do not need wait for the Model to tell me about it This is wrong for two reasons gt The Model can veto the operation for some reason The operation will not occur gt Other Controllers concurrently invoke operations on the Model Some other operation can slip in between which fundamentally changes the rendering and makes any assumptions about it invalid We applied this pattern to the design of the ActiveX client for the OrderEntry application The ActiveX client plays two roles View and Controller Referenced EJBs hosted by WebSphere Application Server are the Model that represents the data and operations on that data Such distribution of the three components in the MVC pattern is called server centric placement Chapter 7 The ActiveX bridge service 125 7 2 2 ActiveX client interface The client is designed to represent the application used by call center agents to place orders for customers It uses the OrderEntry Application EAR file both on the client and the server The EAR file has been modified to include the client jar file see 7 8 Modifying the EAR file for the ActiveX J2EE client container on page 148
319. the TriggerPoint object performs a sequence of tasks to fire a BRBeans rule The tasks include finding filtering firing a BRBeans rule and returning rule results Strategies are Java objects provided with the BRBeans framework that influence the execution of TriggerPoint methods Four strategies can be used to modify behavior of the TriggerPoint object see Figure 3 5 Rule Client trigger lt ME EJB TriggerPoint Servlet 2 Java Class return result Figure 3 5 Using strategy objects in the BRBeans framework The strategy objects are gt Finding strategy Two implementations of this strategy DefaultClassifierFindingStrategy and DefaultNonClassifierFindingStrategy perform a search for classifier and base rules 24 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide respectively The order in which BRBeans rules are found is determined by the rule precedence The rule with the highest precedence lowest value is found first and the one with the lowest precedence is found last The rule precedence is specified in the Rule Management Application on the Other tab of the Properties window Filtering strategy The finding strategy can return more than one BRBeans rule Several implementations of the filtering strategy provide different ways to filter rules found by the framework Accept Any Any number of rules returned by the finding strategy will be used default Accept One One rule i
320. ting to nameservice 197 create and activate servant object 197 development 156 development for EJBs 158 EJB as CORBA client 161 EJB as CORBA server 161 enable CORBA traces 186 exporting object reference 197 IBM client of the Customer EJB 164 interoperability with an EJB 161 locating a server object 155 putting the ORB into an active state 198 role in J2EE 157 task 157 VisiBroker client of the Customer EJB 177 WebSphere Application Server Enterprise Edition CORBA support 159 WebSphere Application Server to third party coexist ence 160 WebSphere Application Server to third party CORBA interoperability 159 WebSphere Application Server to WebSphere Appli cation Server scenario 159 CORBA Common Object Request Broker Architecture 154 CORBA C Software Development Kit SDK 3 CORBA interoperability 3 CORBA Language Mapping 155 CORBA services 153 155 CORBA support 236 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide WebSphere Application Server support scenarios 159 COrderClerk 128 CSI Client side Internationalization 108 Currency helper function 135 Customer Table Layout CSTMR 11 D database index 47 Def command 58 Delphi 123 dependent rule 41 42 44 46 District Table Layout Dstrct 10 E EJB CORBA development 158 CORBA interoperability 161 creation wizard 68 Enterprise Java Bean v 2 0 52 Enterprise class functionality 3 enterprise class functions 2 enterprise class quality of s
321. tion Server Enterprise Edition 4 0 A Programmer s Guide Overview of the OrderEntry application This chapter introduces the OrderEntry Web application that is representative of a commercial application This application lies in the foundation of the programming examples we supply in this book To make it easier to read this book the OrderEntry application omits some of the attributes of the real life application This chapter also describes the layout of the database tables used in the application Copyright IBM Corp 2002 5 2 1 Introduction The material in this redbook is covered based on the OrderEntry application This application is used throughout the book to provide a hands on experience with WebSphere Enterprise Services We show the advantages offered by WebSphere Enterprise Services in improving the application in several directions by gt Integrating the OrderEntry application with other applications within the same fictitious company CORBA services gt Developing a new message driven entry channel for processing orders in the OrderEntry application JMS Listener gt Externalizing the business rules and making them easy to change without modifying the OrderEntry application gt Simplifying the code and making it less error prone with the WorkArea service gt Adding the Internationalization service to process requests coming from different geographical regions gt Letting the existing ActiveX components
322. tion for the client and the server 3 Develop the server program The server acts as a container for a variety of CORBA objects each of which supports one IDL interface The server developer must add code to provide the business logic for each type of CORBA object The server makes its CORBA objects available to clients by exporting object references to a well known location 4 Develop the client program The client uses the IDL compiler generated mappings to invoke operations on the object references that it obtains from the server 5 Build the application with a language specific compiler linker and archiver You can find further reading material at http www omg org 8 1 1 Role of CORBA in J2EE This section discusses what CORBA is used for and how to use it within the J2EE platform The task of CORBA CORBA is the J2EE distributed inter language specification which allows interoperability with external applications The most basic interoperability feature in the J2EE specification is called JavalDL It allows applications to access any CORBA object written in any language using the standard IIOP protocol Due to the J2EE security restrictions all J2EE application component types should only act as CORBA clients The only exception is the J2EE application client Figure 8 4 shows the position of CORBA in the J2EE architecture Browser Enterprise Ay Container Container CED Information System J2EE
323. tion or many transactions managed as a single unit of work UOW requires in case of process failure a new mechanism to roll back or compensate for changes that have already been committed The compensation mechanism doesn t dictate an all or nothing rule for the process Rather it invokes a second process to analyze the results of the failed process and perform the steps to compensate for the failure For example think of a process that runs multiple J2EE transactions in a single UOW Failure of one of the J2EE transactions doesn t mean that the committed transactions have to be rolled back It is more intelligent to re run the failed transaction or perform some other steps and continue with the process gt It allows the building of complex solutions from existing Java components using a visual rather than coding environment The solution is built using a hierarchy of different BPBeans components These components are then connected and grouped together to form larger reusable components A special modeling tool called Application Builder for Components ABC is used to build a hierarchy of different BPBeans components The whole idea of the BPBeans framework is to make the application building process easier faster and more productive by gt Supporting the advanced business process modeling mechanism gt Promoting reusability of BPBeans components as much as possible gt Separating control logic from the Java co
324. to standard the Model View Controller MVC pattern This is a well known recipe for writing software that provides simultaneously different views on the same set of data It provides a clear way of encapsulating a different part of an application in the different components The roles participants in the MVC pattern are see Figure 7 3 gt The Model encapsulates application state data and operations that modify that state A model is meant to serve as a computational approximation or abstraction of some real world process or system For example the Model of a shopping cart of an e commerce application contains the identity and number of purchased items and offers operations to add and remove items from the shopping cart gt The View is responsible for presenting rendering the information contained in the Model in a particular output modality For example a graphical View may render a shopping cart as a list showing the items and their number plus a remove button next to each item A View is an observer of the Model and therefore also depends on the Model At initialization time the View registers with the Model to express its interest in any changes of the Model s state Whenever the Model changes states it notifies the View by sending it an EventObject that contains the state change The View then updates its rendering gt The Controller accepts input from the user in a particular modality interprets the input the i
325. torage area where multiple pieces of data can be stored and all the data is passed along transparently by the WebSphere Application Server This storage is associated with a single thread Data is stored as a name value mode triplet This chapter describes gt When to use WorkArea How the WorkArea service works Using WorkArea in the example application Ways to use WorkArea beyond the example application How to configure the WorkArea service in the WebSphere Application Server YYY Yy Note To understand the structure of the OrderEntry application and to run it read the instructions in Appendix A Downloading and installing the OrderEntry application on page 221 Copyright IBM Corp 2002 91 5 1 WorkArea overview WorkArea is best used to store data that is required by many parts of the application If we pass this data as parameters method signatures would quickly become cluttered Even methods that don t need the data may have to pass it along to other methods that require it Also if future enhancements require additional data to be passed or the type or length of the data must change all methods that use or have to pass this data would have to change By using WorkArea only those methods that actually use the data would have to handle it Because WorkArea is not explicitly passed there are no extra parameters for methods that don t need the data In this sense WorkArea is similar to the security or transaction
326. tory Documents Directory Security HTTP Headers Custom Errors Vhen connecting to this resource the content should come from A directory located on this computer A share located on another computer A redirection to a URL Local Path CABMWWVebSphere AppClientiEnterpriseise Browse J Script source access IV Log visits IV Read JV Index this resource Write I Directory browsing Application Settings Application name Order Entry Application Remove Starting point Defau OrderEntry_ASP Configuration Execute Permissions Scripts only v Application Protection Hian Isolated X Unload omen Help Figure 7 5 Windows 2000 Properties window for an ASP application Chapter 7 The ActiveX bridge service 145 OrderEntry_ASP Properties 2 xi Virtual Directory Documents Directory Security HTTP Headers Custom Errors When connecting to this resource the content should come from CF A share located on another computer A redirection to a URL Local Path C AIBM WebS phere AppClient Enterprise Browse Access Permissions Content Control Content Control V Read V Log access IV Index this directory F write I Directory browsing allowed Application Settings Name Order Entry Application Remove Starting Point lt Default Web Site gt OrderEntry_ASP s 5 Configuration IV Run in separate memory space isolated proc
327. tracing Internationalization service function 117 Userlnternationalization interface 108 using in the example application 112 Internationalization Service API 108 Internet Inter ORB Protocol IIOP 154 interoperable object reference IOR 156 interoperation 159 invalid rule state 25 invocation context 108 invocation internationalization 110 invocation locale and time zone 117 InvocationInternationalization interface 110 invoking component 107 IOR interoperable object reference 156 182 Item Table Layout ITEM 13 J J2EE client container 129 role of CORBA 157 specification 157 J2EE Connector Architecture 4 Java 2 Platform Enterprise Edition J2EE 2 Java Abstract Windowing Toolkit AWT 93 Java Message Service JMS Listener 3 Java methods 137 JavaBean context 215 JavalIDL 157 JClassFactory 128 JClassProxy 133 JMethodArgs 138 Index 237 JMS Admin tool 55 78 advanced facilities 84 APls 52 defining physical queues 55 defining resources 55 destination 52 58 publish subscribe model 76 support 52 testing sample code 74 JMS Listener 51 52 63 80 bean managed transaction BMT 85 begin method 94 complete method 96 container managed transaction CMT 85 exception handling 86 JNDl entries 61 manager 63 MaxSessions 86 security 88 thread 86 threading 86 transaction support 84 wsqcf 85 wstcf 85 XML configuration file 65 81 JMS point to point 51 52 configuring 53 core components 54 JMS Provider 54 61 80 JMS pu
328. tryWeb folder As in previous examples the source code for the rules is located in the source rules folder CalculateOrderTotal is a rule implementor that encapsulates the total order amount calculation functionality The initialization parameters for the init method are the names of dependent rules that are used by CalculateOrderTotal and a sales tax rate see Example 3 11 Example 3 11 Implementation of the CalculateOrderTotal init method public void init Object parms String dependentRules String userDefinedData IRuleCopy rule throws BusinessRuleBeansException Store the initialization parameters Tax rate taxRate Float parms 0 floatValue Dependent rules this dependentRules dependentRules initialized true CalculateOrderTotal uses two dependent rules CalculateDiscount and CalculateShippingCharge We reviewed the source code for the discount rules in Base rules implementation on page 33 CalculateShippingCharge see Example 3 12 returns a shipping rate based on the type of shipping selected by the customer ground priority or express Shipping types and rates are specified as initialization parameters to the CalculateShippingCharge rule Example 3 12 Implementation of the CalculateShippingCharge fire method public Object fire TriggerPoint tp Object target IRuleCopy rule java lang Object parms throws BusinessRuleBeansException float shippingCharge 0 String shippingType null
329. ty can be also wrapped in Activity Wrapper Process Repeat the following steps as many times as your application logic requires Remember that you start assembling the application from the most basic components Gradually you create more complex components until you assemble the whole application refer to Figure 9 1 on page 211 The steps include a Select the specific components and wrap them in the appropriate process type b Make the necessary connections between the components in the process c Define the necessary context properties Add the Client Type to the BPBeans model Client Type in the model represents the entry point for the components not necessarily BPBeans components outside the BPBeans application to invoke it 8 Connect Client Type to the input ports of the BPBeans application 9 Export the application model from the ABC tool The tool creates a JAR file with the application model and a batch file to start the application 10 Develop an application client code This is the code from where you will invoke your BPBeans application EJBs JSPs or servlets are good candidates for this step Example 9 1 shows the sample code for invoking the BPBeans application We used OrderEntryClerk EJB from the OrderEntry application to write this code Example 9 1 Sample code from the OrderEntryClerk EJB Begin Business Process Beans rr ae e a i i mport mport mport mport mport mport mport
330. ubs are created during development and are therefore part of the EAR file However if it is considered impractical or unsecure to hold the whole EAR file on each client workstation then the stubs can be extracted from the EAR file and added to the classpath manually If the whole EAR file is added to the client workstation then the location of the file is passed to the client container when it is initialized within the ActiveX process If only the stubs are installed on the client then the Activex process doesn t need to initialize a client container within the JVM and can reference the EJB home interface via the full JNDI name 7 4 5 Launching a standard Java J2EE application in a client container To run a client application in a client container using the standard J2EE Application Client the launchclient bat file is run It first calls the setupCmdLine bat file to add various environment variables before running the client inside the client container using the JRE provided with the J2EE Application Client 7 4 6 Launching a client container in an ActiveX process To give the ActiveX client the access to the J2EE application client container the launchClientXJB batch file is run launchClientXJB myClientApp exe Since this command needs to be run each time the application is restarted it may be worth creating a simple batch file with contents similar to C IBM WebSphere AppClient Enterprise bin launchclientxjb myClientApp exe The
331. ue 4 Chapter 7 The ActiveX bridge service 135 End If End Function Java Long as Currency Usage Example Dim LC As MungeCurr Dim L2 As Munge2Long Assign a Currency Value really a Java Long to the MungeCurr type variable LC Value cyTestIn Coerce the value to the Munge2Long type variable LSet L2 LC Perform some operation on the value now that we have it available in two 32 bit chunks L2 LoValue L2 LoValue 1 Coerce the Munge value back into a currency value LSet LC L2 cyTestIn LC Value 7 5 2 Accessing a Java class The FindClass method is used to access a Java class It takes the full name of the class as a parameter and returns a JClassProxy object Dim myClassProxy as Object Set myClassProxy oXJB FindClass com myApp MyClass myClassProxy can be used in the same way as the MyClass to access static methods and fields Example 7 7 shows how to access class static methods Example 7 7 Invoking Java class methods through the JClassProxy Dim myClassProxy As Object Dim myString As String Set myClassProxy oXJB FindClass com myApp MyClass myString myClassProxy getName Example 7 8 shows how to access class static fields Example 7 8 Accessing Java class fields through the JClassProxy Dim myClassProxy As Object Dim myString As String Set myClassProxy oXJB FindClass com myApp MyClass myString myClassProxy name In the above examples the getName method and name attr
332. ue WebSphere Application Server Enterprise Edition solves this problem with the extended messaging support JMS Listener JMS Listener manages the task of retrieving messages from a JMS destination queue This significantly reduces the development effort for the JMS enabled applications The implementation of JMS Listener within WebSphere Application Server Enterprise Edition is very close to the current level of the Message Driven Bean MDB specification that is part of the Enterprise JavaBean version 2 0 EJB 2 0 specification being ratified by Sun JMS Listener can be considered as an input mechanism to access business logic that already exists A client application places a message on a JMS destination queue JMS Listener detects the message and invokes a message bean according to the listener s XML configuration file The work is then delegated to other components of the system such as Enterprise JavaBeans EJBs or JavaBeans In this scenario business logic is separated from message handling Two models currently exist for JMS gt JMS point to point Messages arrive at a JMS destination a physical queue They are then routed to an EJB called the message bean The message bean performs processing that can be based on the content of the message This is illustrated in Figure 4 1 WebSphere Application Server MQ Client i Business Logic Aaeieeior gt s M gt JMS Listener gt Message Bean
333. uld not be accessible from outside Customer dll Compiling and linking the stubs First you need to compile the stubs and the valuetype implementation to the object files The output is Generating the Customer_merged object cl 1 0E_HOME corba client vb2ejb 1 0E_HOME corba tools I MSVCDir include I VBROKERDIR include I VBROKERDIR include stubs DWIN32 D_USE_NAMESPACE nologo MD GX c DORB_VisiBroker DSOM DLL_Customer Customer_merged_c cpp Chapter 8 The CORBA services 179 Customer_merged_c cpp Customer_merged_c hh 24 warning C4067 unexpected tokens following preprocessor directive expected a newline Customer_merged_c hh 27 warning C4067 unexpected tokens following preprocessor directive expected a newline Generating the value type interface objects cl 1 0E_HOME corba client vb2ejb 1 0E_HOME corba tools I MSVCDir include I VBROKERDIR include I VBROKERDIR include stubs DWIN32 D_USE_NAMESPACE nologo MD GX c DORB_VisiBroker DSOM_DLL_Customer Vtlib_c cpp Vtlib_c cpp Generating the value type implementation objects cl 1 0E_HOME corba client vb2ejb 1 0E_HOME corba tools I MSVCDir include 1 VBROKERDIR include I VBROKERDIR include stubs DWIN32 D_USE_NAMESPACE nologo MD GX c DORB VisiBroker DSOM_DLL_Customer Vtlib_I_vb cpp Vtlib_I_vb cpp Then you must link the stub library and DLL which produces the output Creating the Customer lib library lib NOLOG
334. ule using the BRBeans framework and examine implementations of several other business rules We provide instructions for developing business rules in WebSphere Studio Application Developer WebSphere Studio Application Developer tool provides an easy and convenient way to create rule implementors and package them in an Enterprise Archive EAR file for deployment in WebSphere Application Server If you don t have access to the tool you can develop rule implementors in other Java editors and use WebSphere Application Assembly Tool to package the EAR file We assume that DB2 is used to persist BRBeans rule data The completed application is deployed in WebSphere Application Server Enterprise Edition 18 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide The following sections explore the necessary steps to develop deploy and run the BRBeans enabled application 3 2 1 Setting up the development environment This section goes through the steps of setting up the environment for developing BRBeans However before you start executing the steps make sure you have completed necessary prerequisites that are described in Appendix A Downloading and installing the OrderEntry application on page 221 Then complete the following steps 1 Import OrderEntry application to WebSphere Studio Application Developer a Start WebSphere Studio Application Developer b Click File gt Import C d e f Double click the
335. urce Options 10 1701 11 2 Console Ready z Details xl Clear Figure 4 12 WebSphere Application Server queue JNDI entries Figure 4 13 shows the queue connection factory definitions for our OrderEntry application To add it follow these steps 1 Right click JMS Connection Factories 2 Select New 3 Specify the JMS connection factory Name and its External JNDI Path 62 WebSphere Application Server Enterprise Edition 4 0 A Programmer s Guide Console View Tools Help eja o x g amp E ag WebSphere Administrative Domain Description JMS Provider Virtual Hosts BG ConnectionFactory IBM MQSeries Server Groups Nodes Enterprise Applications P23BK66H_sampleApp Resources General HE JDBC Providers JavaMail Sessions Name ConnectionFactory URL Providers E J2C Resource Adapters External JNDI path JOrderEntryiJMS QCF JMS Providers Description IBM Maseries oe amp H E JMS Destinations JMS Provider IBM MQSeries Type Time Event Message Options E 10 17 01 3 50 Command ConnectionFactory1 remove running a z E 10 17 01 3 50 Command ConnectionFactory1 remove completed succes Details E 10 17 01 3 51 Command ConnectionFactory2 remove running x Clear Figure 4 13 WebSphere Application Server queue connection factory JNDI entries The queues and t
336. ure 4 5 Defining and creating physical queues within MQ Explorer the JMS Provider 4 2 3 Defining JMS resources A key part of JMS implementation is the administration of JMS resources This is performed within the JMSAdmin tool This section discusses its configuration Chapter 4 Extended Messaging Service 55 Figure 4 6 shows the relationship between the components in the JMS Provider MQSeries and WebSphere Application Server All JMS resources are created and given a JNDI path by the JMSAdmin tool The JMS destinations which are defined in the tool become the physical queues provided by MQSeries For each JMS resource there is a corresponding JNDI entry defined in WebSphere Application Server Note The JMS resource objects are bound into the namespace by the ResourceBinder object when WebSphere Application Server starts After the server is started the entire namespace can be viewed by using the DumpNameSpace tool shipped with WebSphere Application Server JMS Provider MQSeries WebSphere Application Server 1 namespace correlation WAS QCF Definitions wsqcf QueueConnectionFactoryBean JNDI Entry JNDI Context Definitions ctx Listen JMS Definition q Atte Listen JMS JNDI Entry correlation Send JMS JNDI Entry Send JMS definition q optional binding pes JMS destination MQ
337. w rule Note The BRBeans suggested method for modifying existing rules is to expire the old BRBeans rule and establish a new BRBeans rule to take effect simultaneously Using this methodology old rules are never deleted They are retained for historical purposes so that if a BRBeans rule is fired with a reference date at some time in the past the correct logic is applied To use Quick Copy follow these steps 1 Select a BRBeans rule in the Rule Management Application 2 Right click the rule and select Quick Copy see Figure 3 4 Chapter 3 The Business Rule Beans service 23 CE o File Edit View Help Rules in folder CustomerRules Status All Folders Rule Namespace CustomerRules DiscountRules OrderRules ShippingRules com Start Date 1 1401 12 01 AM 1 1 01 12 00 AM 1 1 01 12 00 AM Properties ig Cut Ctrl X 9 Specie Copy Ctrl C Paste City New Export Bee Delete Rename 4 Rule Selected Figure 3 4 Using Quick Copy Placing trigger points Trigger points are pieces of application code that make a call to a BRBeans rule Trigger points can be placed in EJBs servlets or Java classes that depend on business logic implemented in BRBeans rules The TriggerPoint object looks up BRBeans rules by names defined in the Rule Management Application Using strategy objects At runtime
338. were done by downstream transaction doRecovery return the exception to the container throw exception A combination of these techniques may be implemented Chapter 4 Extended Messaging Service 87 gt The message itself contains the number of retry attempts that have been made int retry msg getIntProperty JMSXDeliveryCount The returned value can be used to determine the exception processing that should take place 4 4 4 Security Messages arriving at a destination being processed by the JMS Listener have no client credentials associated with them The messages are anonymous In the current release the security model provides a solution where a JMS Listener assumes the EJB server process credentials for the invocation of the stateless session bean In configuring the secure WebSphere Application Server it is necessary to configure gt Resource security for the stateless session bean to allocate its security method groups gt Security permissions for the bean create and onMessage methods so they are accessible by the given EJB server principal This security model is to be reviewed for the next release 4 4 5 MQSeries clustering Message distribution managed through the use of MQSeries clusters is an efficient way to manage point of failures in the message network The cluster manager can detect failure with the physical machine or the message queue availability and route messages to queues that are av
339. will be useful with almost any activity for example the sendMessage method or the getResource java lang String resourceName method and so on Process Process in the BPBeans framework is responsible for managing all activities and other processes that it contains A process defines gt How it creates starts or stops an instance of an activity or process gt How the outcomes are handled gt How transactions are handled Chapter 9 The Business Process Beans service 213 To be as flexible as possible the BPBeans framework provides several process types gt Activity wrapper process This process provides a way to combine Activity Resource described later and transaction support optional but usually included as part of the process Transaction support is achieved by adding a BPBeans component called Unit of Work UOW Director to the process VOW Director demarcates the transaction boundary All activities and processes contained inside Activity Wrapper Process are executed as a single transaction UOW Director supports open nested transactions gt Compensation pair process This process type combines two tasks The first task is the main task and performs some business logic The second task is a compensation task It is executed only when the main task fails The steps that the second task executes depend on the application logic they can be as simple as rolling back the changes or they might be more complex
340. with the properties from WorkArea 0 that have not been overridden That method can also create another nested WorkArea over WorkArea 1 Figure 5 3 shows a double nested WorkArea 2 In WorkArea 2 again we changed the value of quantity to 3 This overrides the value in WorkArea 1 All the other WorkArea properties from WorkArea 1 are visible If we remove the firstName property it will no longer be visible in the current method However when control returns to the caller method where we created WorkArea 1 the firstName property will again be visible Work Area 0 Work Area 1 Work Area 2 name value mode quantity 3 normal itemID 000003 fixed normal last Name Smith read only customerID 0001 fixed read only MINOS APAA read only itemPrice 4 50 read only shipping ground Figure 5 3 Double nested WorkArea Note A very good analogy to the concept of the nested WorkAreas is the class hierarchy in Java For example base class A has three methods x y and z We can create another class B that inherits from class A Class B overrides method z and defines some other methods If we invoke method z inside the object of class B it finds this method implementation in class B If it invokes method x or y it finds their implementations in class A In this example class A is equivalent to the original WorkArea and class B is equivalent to the nested WorkArea Creating a nested WorkArea In the example if we try to use th
341. ws the code for performing a credit history check The isCreditableFor method is called with the customer s first name last name and the total of the order as parameters Example 8 17 Calling the CreditinstituteWrapper class private CreditInstituteWrapper institute null public boolean checkCreditability boolean isApproved true String info The customer is assumed to be approved check connection if this institute null try this institute new CreditInstituteWrapper connection is available try Support Customer customer itemsViewBean getCustomer double orderTotal itemsViewBean getOrderTotal isApproved this institute checkCreditability customer getFirstName Chapter 8 The CORBA services 203 customer getLastName orderTotal info catch PersonNotFound ex no error situation info Customer not found in CreditInstitute System out printIn info ex printStackTrace catch InformationConfidential ex no error situation info Information confidential System out printIn info ex printStackTrace jtemsViewBean setIsApproved isApproved itemsViewBean setApprovedInfo info return isApproved Since the wrapper forwards the exceptions the ApplicationManager has the possibility to decide how to react on the user exceptions If a user exception occurs the customer is assumed to be creditable Initializing the Java c
342. xamples in the file file WAS_HOME Enterprise samples index htm Compiling and running the mentioned example gives a good hint in regard to which data types are supported Note For our sample we could see that javax ejb CreateException and javax ejb FinderException are not supported by VisiBroker 4 5 We go through the basic steps which are discussed in the following subsections 1 Set up environment 2 Build the client 3 Run the client Setting up environment To set up the needed environment variables for building and running the client you have to start a command prompt and execute 0E_HOME corba client vb2ejb set_vb2ejb_env bat Some settings need to be done on the server side to properly transport the string parameters The IBM client doesn t need this setting but it doesn t prevent the IBM client from running In the WebSphere Administrative Console you have to change the JVM settings of the application server that runs the OrderEntry application You have to add the system property as shown in Figure 8 8 General Advanced File Transaction S Services Custom i System Properties Name value Add com ibm CORBA ORBWCharDefault UCS2 ia i Advanced JVM Settings Generated Command Line Arguments EDcom ibm CORBA ORBWCharDefault UCS2 _ Figure 8 8 JVM settings for VisiBroker Chapter 8 The CORBA services 177 Building the clie
343. xt method of EJBs 6 3 2 Retrieving and using the caller internationalization context Once we bind to the Internationalization service we can retrieve the caller internationalization context and use it Example 6 5 shows a method in the ItemsViewBean that retrieves the caller context and uses it to format the currency amount according to the invoking component s locale Note that if currency exchange rate must be calculated we would have to call a method to do that in the place indicated The method to calculate exchange rate is beyond the scope of this example However note that because the method executes on a WebSphere Application Server Enterprise Edition server with the Internationalization service enabled it also has access to the caller locale There is no need to pass locale as a parameter to the method Example 6 5 Retrieving and using the caller internationalization context import com ibm websphere i18n context import java text NumberFormat private Internationalization callerI18N private float orderTotal 0 public String getOrderTotalForDisplay java util Locale callerLocale java text NumberFormat nf float currencyAmount callerLocale callerI18N getLocale nf java text NumberFormat getCurrencyInstance callerLocale This is where the exchange rate should be calculated currencyAmount calulateExchangeRate orderTotal return nf format currencyAmount Important Some browsers may send a
344. y Activity gt Checks Activity s state 9 2 4 Outcome decider A result of a process execution is defined through its outcome In some cases like in case of a Concurrent process the outcome of a process is established by analyzing the outcomes from all contained processes in a special component Outcome decider This component can analyzes the outcomes of the same type In the case when tasks in a Concurrent process produce outcomes of different types a BPBeans component called Outcome Mapper is used Outcome Mapper converts the outcomes from one type to the outcomes of another type This approach of using specialized objects to convert and analyze the result of a task helps to achieve the high reusability of the BPBeans components Chapter 9 The Business Process Beans service 215 9 3 Generic steps in BPBeans development Despite the variety of the BPBeans components there are generic steps in developing an application in the BPBeans framework Important This section should be used in conjunction with BPBeans Javadoc and the programming guide to completely understand and use the BPBeans framework The steps are outlined here 1 Design the application Since this step is big in itself we don t concentrate on this step because it is not the topic of this section 2 Develop the following BPBeans components in any Java IDE Activity Activity has to implement the com ibm bpbeans Activity interface or it can ext
345. y java comp env For example using the helper method XJBGetEJBHome to retrieve the Customer EJB s home interface object in the OrderEntry application the code in the ActiveX_EJBHomeRef module see Example 7 18 Example 7 18 Getting a home interface object Set CustomerHome XJBGetEJBHome oXJB LocalContext java comp env ejb CustomerBean com ibm itso roch wasaejb CustomerHome 5 Click the Bindings tab 6 Type the JNDI name the JNDI name of the referenced EJB The JNDI name can be found by highlighting the corresponding EJB under the appropriate EJBModule in the left hand pane Then selecting the Bindings tab in the lower right hand pane The JNDI name is the actual location of the EJB in the JNDI Name Space 7 Repeat this process for any other EJB reference required by the client application 7 8 4 Optimizing the EAR file If there is a concern with security or the size of EAR file you can optimize the EAR file The Application Assembly Tool can now be used to slim down the EAR file for use on the client AAT should be used because it will also remove all references to the redundant components The following components can be removed from the EAR file Any WAR files Any DLLs or XML files related to building the application database Java source code There may also be a requirement to remove this for security reasons Unreferenced EJB stubs and ties YYY Yy Chapter 7 The ActiveX bridge service 151 152 WebSphere Appl
346. y the caller Table 5 1 Permissible operations on properties with a given mode Mode If using set operation If using remove operation Property is set with a new value Property is removed Read only PropertyReadOnly exception Property is removed Fixed read only PropertyReadOnly exception PropertyFixed exception Property is set with a new value PropertyFixed exception In the example application we would probably want to make the customerlD field both fixed and read only Example 5 6 shows the change to the call of the set method to include the third parameter Example 5 6 Setting the mode for a property import com ibm websphere workarea Context ctx getInitialContext UserWorkArea workArea getWorkArea ctx workArea set customerID id PropertyModeType fixed_readonly These are the possible values for the mode defined by com ibm websphere workarea PropertyModeType PropertyModeType normal PropertyModeType fixed_normal PropertyModeType read_only PropertyModeType fixed_readonly YYY Yy 5 3 2 Nested WorkAreas Nested WorkAreas are used by remote methods to override add or delete properties in a WorkArea received from the client Figure 5 1 shows the original WorkArea created by the client with four properties The diagrams used in this chapter differ somewhat from those in other documentation to more clearly show the process of overriding the properties Chapter 5 The WorkArea service 97 Work Area 0
347. you send 10 requests to this method you will get on average True four times False four times PersonNotFound 1 time InformationConfidential 1 time YYY Yy Chapter 8 The CORBA services 199 Building the test client The test client gives you the possibility to test the server without starting WebSphere Application Server and running the OrderEntry application To build the test client you simply have to run a makefile cd 0E_HOME corba server ejb2orbix nmake f makefile ejb2orbix testclt This execute all the steps which are described in the following subsections gt Generating the test client sources gt Modifying the generated test client sources gt Compiling the test client code The build of the test client takes place in the subdirectory testclt To delete all the generated files and directories you call cd 0E_HOME corba server ejb2orbix nmake f makefile ejb2orbix cleantestclt Generating the test client sources The Orbix Code Generation Toolset is used to create the sources and the build file for the Java test client The output of the makefile execution is shown here Generating the test client sources idlgen java_poa_genie tcl ns all dir testclt CreditInstitute id CreditInstitute idl java_poa_genie tcl creating testclt idlgen IT_GenieRandom java java_poa_genie tcl creating testclt TestPackage com ibm itso roch credit CreditInstituteCaller java java_poa_genie tcl creating te
348. ystem starts a transaction to do the initial receive but the message bean is not part of the same transaction if it is using bean managed transactions Container managed transactions CMT Only two of the six transactional policies are meaningful for a message bean since a client is not involved and the onMessage method is the originator of the work request to the server The two policies are gt Required The configuration file for the message bean should also specify Transactional True This ensures the message is read within a transaction and the processing within the onMessage method occurs within the same transaction refer to Table 4 1 gt Not Supported Table 4 1 EJB transaction attributes CMT behavior Transactional True Transactional False EJBs with CMT and Required The initial read and execution of Global transaction is not started onMessage are both part of the same transaction EJBs with CMT and Not The initial read is within a Global transaction is not started Supported transaction but the onMessage method is not part of the same transaction EJBs with Bean Managed The initial read is within a Global transaction is not started Persistence BMT transaction but the onMessage method is not part of the same transaction Chapter 4 Extended Messaging Service 85 If the Transactional value is set to False the message is not read as part of a transaction although the onMessage method may b

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