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Procasor Project - Student`s research project server

1. Tokenizer Collins parser MXPost tagger and MorphA Possible states are Q Tool is closed Q Tool is starting Q Tool is running 8 3 Project Window 8 3 1 8 3 2 After creating a new project or opening an existing one Project window appears Project window for the Marketplace project example is shown in Figure 8 2 Most of the window displays entities their models and use cases and provides means to manage them The right column contains the list of project s conceptual objects Chapter 3 Entity Management Entities contained in the project are shown in the upper part of the Project window Three buttons are available Add Delete and Edit Clicking Add or Edit allow to edit entity properties Fields Entity name and Acronym have to be filled and have to be unique in the scope of the project The acronym has to start with a letter and contain letters of digits only Lower part of the window provides access to the entities hierarchy Parent and or children entity may be chosen here Hierarchy of all entities can also be accessed using the Hierarchy window Section 8 7 Model Management Every newly created entity contains one model named default For adding or editing models similar buttons as for entity editing are available Model editing adding window is similar to the entity editing window Instead of the acronym this window contains the use case expression The use case expression describes possible u
2. appropriate Pro cases resulting in a model Pro case 3 3 3 UML State Machine generation UML State Machines are another way to specify the behavior of a component A UML State Machine consists of states and transitions and defines their layout in a diagram The Procasor project With Procasor you can either create a UML State Machine for a single use case or you can export the whole project to UML with state machines for all use cases You can display and edit these UML diagrams with your favorite UML modelling tool Chapter 4 Linguistic tools application 4 1 Introduction This chapter describes linguistic tools and their integration into the use case analysis At first we intro duce goals of linguistic analysis in Procasor after that we define structure for passing results of lin guistic analysis the parse tree and finally we describe individual tools and their roles in these processes Application of linguistic tools is the first step of use case analysis Each sentence representing one use case step is sequentially processed by these tools in order to acquire information about structure of the sentence and role of each word in the sentence This information is stored in a structure called parse tree The parse tree for the sentence is then passed to following processes which take part in use case analysis Acquiring a parse tree of a natural language sentence is the main goal of the application of linguistic too
3. have successfully tested Procasor with Java version 1 5 we recommend Java 1 4 distribution A 2 Installing Procasor Procedure 1 Make sure that the Java tm bin directory is referenced in the PATH environment variable and at the same time check that the Java tm runtime in PATH is the right version java version java version 1 4 2 06 Java TM 2 Runtime Environment Standard Edition build 1 4 2 06 0503 Java HotSpot TM Client VM build 1 4 2 06 503 mixed mode 2 Unpack the Procasor distribution to your installation directory gzip d c procasor tar gz tar xvf ls procasor bin config documentation tools 3 Run Procasor Procasor can be run by the procasor script from the bin directory procasor bin procasor A 3 Content of the Installation Directory bin Contains the script for running Procasor procasor Script for launching Procasor 31 Installation Manual config documentation documentation api exports imports lib logs projects src tools Contains configuration files for linguistic tools used in application and the property file for storing user s settings config xml properties Contains Procasor documentation in HTML and PDF Acrobat formats The documentation consists of two books User documentation and De veloper documentation Contains Procasor API documentation in HTML format Directory recommended for exporting projec
4. result e Goto target Shows the target step if the sentence type is set to goto action In the submenu another step may be chosen as the target e Included use case Shows the acronym of the included use case if the sentence type is set to use case inclusion In the submenu you can choose another use case to be included You will be offered changing the text of the step to a predefined text Handles included use case failure Sets a special option for this step Only available for condition steps that extends a including use case step See Section 7 1 for effects of this option 27 User Interface Import steps from file Imports steps for this use case from a file See Section 8 8 for details e Export use case to txt Exports the use case to the selected file in text form e Export use case to UML Exports the use case to the selected file in the UML format 8 4 2 Analysis Tabs The right side of the Use case window is composed of four tabs 8 4 2 1 Description Tab Consists of two parts The left one is contains an the same entries as the dialog for creating use cases Section 8 3 3 The right part displays a summary of the step analysis result including the action type subject indirect object and action label 8 4 2 2 Parsed Tree Tab This panel displays results from the parsing tools and tree analysis The biggest part of the tab is filled with the tree of the step s sentence It combines the res
5. To create a new use case use the Add button in the Use case box Use case name and acronym have to be filled In addition you have to specify the actors of the use case After saving the use case a new use case window Section 8 4 appears Here you may change the information entered in the previous step if necessary Example Select the MIS entity in the entities table then press the Add button in the Use case section of the Project frame A dialog for use case creation appears Fill Seller submits an offer into the Name field and UCI into the Acronym field There already is one line in the Actors table entity MIS is set as the System under Design SuD Click next line in the Actors table marked and choose Seller as the primary actor of the use case Press the Save button Before you start entering steps to the use case make sure linguistic tools are ready If the Parser progress bar in the left lower corner is green everything is alright If the progress bar is red linguistic tools have to be started See Section 8 2 2 where manipulation with linguistic tools is described B 4 Adding Steps to the Use Case Now you may start adding steps to the use case Steps are written into two tables in the left part of the use case window upper table for the main success scenario lower one for extensions and variations When the text of a step is confirmed e g Enter pressing selection changing the step is automatically
6. analysed Result of the analysis consists of the parse tree step type acting entities and token All results are displayed in the tabs in the right side of the window and every one of them can be changed manually To modify the token switch to the Token Tab Section 8 4 2 3 Chapter 6 gives detailed information on the usage of this tab Example Click the first line in the Step text column of the upper table write the text of the sentence Seller submits item description and press Enter Sentence will be analysed It is recognized as a request receiving action Seller being the source of the request Switch to the Parsed tree panel Here you can see the tree of the sentence result from the linguistic tools analysed results and token submi tItemDescription is the event token for this step we are satisfied with it and will not change it 33 Getting started Example Click the arrow on the right of the previously added line A new branch is created in the lower table and appended to the first step therefore marked la Enter Item not valid as the text of the condition and leave Extension as the type of the branch Step type is condition the event token is itemNotValid This time we may be unsatisfied with the token and will change it manually We switched to the token tab activate the Write by hand pane and enter itemInvalid as the new event token Example Again click the arrow on the right of the previously added lin
7. are mentioned For full understanding previous chapters are supposed to be read Particularly Chapter 2 and Chapter 3 Procasor graphical interface is designed for simple and intuitive creation of the use cases It provides access to all features described in previous chapters To run Procasor please read the Appendix A carefully and follow its instructions 8 2 Main Window 8 2 1 When Procasor starts main window is displayed Individual windows will take places inside of this main window The bottom bar consists of linguistic tools information field and of the message area Main menu is located in the top of the window Main Menu Main menu serves to simplify project editing parsing tools control and preferences setting Most im portant elements from the main menu have their own shortcuts Menu consists of four items Project Parser Window and About Description of the individual items follows Project menu e New Ctrl N To create new project Displays the new project dialog Project s name has to be filled Open Ctrl O To open existing project If the newly opened project contains unanalysed steps and linguistic tools are running or starting user may choose to analyse the steps e Close Ctrl L To close the active project Save Ctrl S To save the active project If project has not been saved yet the Save as dialog appears Files are saved in folder projects by default Procasor projects use the
8. lios etie Pete eR e rei orb die 20 7 3 Creating a Model Pro case 20 0 0 cece cece cece cece cece cece ce eece eens em em e mee mee men hene 20 TA Creating a UML State Machine s sssi erriei sseni ten e re Re ERE Re SERE IRE 20 8 User AA AN 22 8 1 Introduction 2 5 e t tee EE Pee HE bot E eite ERU E e Abas Pa ea reet desee 22 82 Main Window AN 22 8 2 1 Main Menu iiss sees corsa desi d Ra e epe repperi 22 8 2 2 Linguistic Tools Control Centre sese 23 8 3 Project WIndOW 5 5 rete ap et eite xe diete easet t prr e shake Stay ERE 24 8 3 1 Entity Management isssssesssssee IH Hem e hee ree rennen 24 8 3 2 Model Management rrr mee rhe ERR ER PIESE E anar 24 8 3 3 Use Case Managements ote esus ite aeee eee m eme mee mener 25 8 4 Use Case Window cimo De ERE RE Ee HE poe P sad Eta ke rotas ree tige 26 8 4 1 Use Case Tables 3er eee eget seek REE EE 26 8 422 Analysis Tabs ou otero iii sesso os 28 lil Procasor Project 8 5 Properties Dialog oec ere teneret E ph vee ee eee ee oorr t de totes 28 8 5 L Editing Seccatid det pent 29 8 5 2 Tokens Sections c s s toe Itb ee taa Hed te Sandon cdaaw ees 29 8 5 3 Parser Sections oio D tu tetas ee ies 29 8 5 4 Auto Save SeCtlOM c osos secret ee iet pi tero eee ee te PR Pop ER ee eH 29 8 6 Token Manager Window 3 dee ERR GE ee ere ev A er A ee asses 29 8 7 Hierarchy of Entities Window sssseseee HH emere
9. main verb Asks is the first verb in the sentence but it may be a padding verb Therefore we search for another verb and find one validate Validate is the principal verb while asks is a padding verb To create the representative object we use the phrase the seller which is the only noun phrase under the main verb Matching with the conceptual object list item offer price assessment price payment method is not successful so we mark seller as the represent ative object 5 2 Detecting Special Actions A special action does not describe an operation request instead it describes a change in the flow of a use case special action should only occur in extensions and variations as their last step We distinguish two basic types of special actions terminate actions and goto actions Another special action including a nested use case is not supported by the Tree Analyser and must be created manually To be recognized as a special action sentence must follow a typical pattern as described in following paragraphs Terminate action may terminate the use case or only the branch extension or variation It may also be an aborting action signaling a failure For a terminate action to be identified verb must come from a list of triggering words end terminate or abort the last identifying an aborting action At the same time subject must be one of a few keywords Use case Extension etc or the sentence must have
10. market the transaction is aborted And the step of verification of item s description will have an extension saying that if the user has an inappropriate history the transaction is aborted The use case for this example is written below Background Figure 2 1 Use Case Example Use Case Seller submits offer Scope Entering an item SuD Marketplace Information System Primary Actor Seller Main success scenario specification Seller submits item description System validates the description Seller adjusts enters price and enters contact and billing information System validates the seller s contact information System verifies the seller s history System validates the whole offer with Trade Commission System lists the offer in published offers System responds with a uniquely identified authorization number Extensions 2a Item not valid 2al Use case aborts 5a Seller s history inappropriate 5al Use case aborts oo Dun Often we describe the system from various level of detail For example we may first design the system as a whole describe its communication with external entities actors In the second step we may design individual components of the system their internal actions and communication between them in detail In this manner entities described in the process of requirement gathering create a hierarchy A single use case only describes the actions performed during a single
11. parse tree generation process Initialization messages from lin guistic tools are also printed on this console Through this console the user can be informed about un expected and error situations that occur in linguistic tools Linguistic tools application 4 4 3 4 4 4 Restarting the Parser The process of parse tree generation is complicated and is provided by different tools witch have to be in compliance with each other therefore the application needs to confront and solve unexpected situations and error behavior of the linguistic tools The errors that occur in linguistic tools are detected and printed on to the Parser console Although we can detect an error occurrence it is very difficult to resolve these errors or to prevent them Therefore we have chosen to restart the Parser when an error occurs and than we process the sentence again In the case an error occurs the remaining linguistic tools are closed and all linguistic processes are initialized again The user is notified about the error by the Parser console which signalizes error oc currence by the red color the option to restart the parser is immediately offered We call the situation when an error occurs a Broken Pipeline situation Linguistic tools processes are monitored by the Parser and important information and messages are stored in the log file which can be useful when searching for reasons of error occurrences In the case an error occurs please se
12. run time license to use the Procasor software Soft ware subject to the restrictions listed below under Scope of Grant D 2 Scope of grant The Licensee may use the Software for educational or research purposes permit others under the Licensee s supervision at the same site to use the Software for educational or research purposes copy the Software for archival purposes provided that any such copy contains all of the original proprietary notices The Licensee may not use the Software for commercial purposes allow any individual who is not under the direct supervision of the Licensee to use the Software redistribute the Software copy the Software otherwise than as specified above rent lease grant a security interest in or otherwise transfer rights to the Software remove any proprietary notices or labels accompanying the Software D 3 Disclaimer The Owner makes no representations or warranties about the suitability of the Software either express or implied including but not limited to the implied warranties of merchantability fitness for a partic ular purpose or non infringement The Owner shall not be liable for any damages suffered by Licensee as a result of using modifying or distributing the Software or its derivatives D 4 Consent By downloading using or copying the Software Licensee agrees to abide by the intellectual property laws and all other applicable laws of the Czech republic and the
13. sentence and contains basic forms of each word The parse tree therefore thoroughly describes each sentence and the object of the use case step analysis Chapter 5 is to extract from the parse tree the needed information about action expressed by the sentence and actors that appear in this sentence Chapter 3 The Procasor project This chapter introduces all the ways Procasor can be used Reading of this chapter is essential for un derstanding what Procasor can offer to the user At first we provide a diagram Figure 3 1 which illustrates all actions that can be taken either by the user or by the Procasor itself In following sections we describe these actions in more detail 3 1 Writing Use Cases Writing the use cases in the Procasor program has some specifics Some steps should be done in certain order In the first place you should understand all the terms about use cases which were explained in the previous chapters mainly in Section 2 1 In this section is explained what you should do How to do it is described in Chapter 8 Before you start writing the use cases you should do some preparation First you should make a list of entities which will appear in the project And set their hierarchical structure which entity encloses others Then it is very useful to write down the list of conceptual objects which you will use in the project The conceptual objects are objects which take a part in modeling project and are used
14. special actions may be an abort action or a goto action Special actions are detected during the transformation and the Pro case is adjusted ac cordingly 2 4 Linguistic Analysis Analyzing use cases is the main goal of the Procasor project and because these use cases are written in natural language our task is to process a natural language sentence in order to acquire information about an action expressed by this sentence Background Because of the complexity of natural language it would by nearly impossible to analyze every sentence properly Yet in a use case as defined in Section 2 1 every use case step is a simple structured sentence written in natural language describing either a communication action among entities involved in the use case or an internal action This determines goals of linguistic analysis For every sentence we need to find action expressed by this sentence and to find all actors involved in this action as well To meet this requirements we employ linguistic tools Section 4 3 which should help us in the use case step analysis The information we need for every sentence can be found in its parse tree Sec tion 4 2 and we use linguistic tools to obtain such parse tree for every use case step The parse tree of a natural language sentence captures the phrase structure of the sentence according to the respective natural language That means that a parse tree describes roles of all words involved in the
15. specification Procasor uses previously generated semantic information as described in Chapter 5 and Chapter 6 For both Pro case and UML State Machine generation a finite state machine is generated first From this finite state machine the behavior specification itself is derived 7 1 Creating a Finite State Machine Note This part is quite technical and difficult Still you are encouraged to read it Knowledge of the rules that direct finite state machine creation may help you to write better use cases that result in accurate behavior specifications We create a finite state machine FSM States in this FSM represent the beginnings and ends of events Transitions with a value represent events event token being the value void transitions represent a possibility that an event follows the previous one First the main success scenario is processed In addition to its states the initial state and the final state of the FSM are generated and connected to the first and last event Then extension and variation we call them branches steps are processed The head of each branch is connected to the state they extend This transition is marked with the condition event of the branch There is a difference between extensions and variations Extensions are appended to the end of the parent event making an optional continuation of the parent event while variations are appended to the beginning making an alternative to the parent event En
16. start with a letter and contain letters and digits only Entities acting in the use case can be chosen in use case editing window First entity System under Design is the owner of the use case and is added automatically Other entities may be added as the 25 User Interface primary actor or secondary actors Only one primary actor is allowed Clicking Edit button shows the most important window for use case writing the Use case window 8 4 Use Case Window 8 4 1 The window allows writing steps of a use case and analysing them The window is divided into two parts The left one contains the steps of the use case the right one contains tabs that display and manage analysed information Use case window is shown in Figure 8 4 Figure 8 4 Use case window O Use case Seller submits offer Gee 5 77 LL IEE EE EG EE wa Mrs Main scenario Mark Step text Y 1 its i inti Token wo 2 System validates the description vB Seller adjusts enters price and enters contac SPECTET GE Dee p a v la System validates the seller s contact informat Analyzis result wv 5 System verifies the seller s history v 6 System validates the whole offer with Trade Request receiving P vi System lists the offer in published offers AOS Request receiving v fan wv B System responds with a uniquely identified a 7 Actor is Seller M Extensions and variations Mark Step text T
17. task We need to employ addi tional technique to specify the overall behavior of a component In Procasor use case expressions are used These expressions serve for combining the information contained in more use cases You can find more information about the use case expressions in Section 3 1 and in the Chapter 8 This information is the starting stage for understanding the Procasor program As you carry on with this user manual you will get on more advanced stages and you will understand more details of Use cases 2 2 Specifying Component Behavior with Be havior Protocols Pro cases Pro cases 2 based on Behavior Protocols 5 are means of specifying the behavior of a component For the described component they enumerate all possible valid sequences of events Pro case syntax stems from regular expressions Atomic events emitted absorbed or internally processed by an entity are the atomic expressions These atomic events are written as follows e Event type is denoted with event for emitted event for absorbed event for internally processed e Acronym of the active entity goes next followed by a dot Not present for internally processed events e Token of the event goes last The token is a label that describes the event it is similar to a method name For example an atomic event could be written as SL submitItem meaning that this event is absorbed by the described entity The entity with acronym SL is the
18. 29 8 8 Importing Use Cases cic rni IIR eI Vequee 29 Bibliography dE 30 A Installation Mandala io E PU ep Hu SA ER een seek 31 A 1 Requirements and Prerequisites esences eee E ERE E E EEO 31 4 2 Installing ProcasOr ista or ette Sy T TERRES 31 A 3 Content of the Installation Directory sesseseee HH 31 B Getting started ii A A Re A E 33 Bol Creating a New Projects e rere exi e be EE Dee eol dere 33 B 2 Addme Entities ra Eie NER 33 B 3 Creating a gt Use Case i sop ste rek eoru r Poser ed p tea Die eee Or ep Rex george 33 B 4 Addmg Steps to the Use Case ci eee bee erede Les diia 33 B 5 Generating Behavior Specification sess 34 C The Marke tplace Project variar i a t prete ved 35 CL Opening the PLlOoject jo oerte n e ae de sees sete yep eee E ivre SENS 35 2 Description arias e NO inte dai os 35 3 Use Case Listes a ioi eere pet nit bo teo ex tenet abere ioa t Eod 36 D License i8 nS o e yat e t e SN etae 40 D I Lacense 1ntormation eiae co peeste eter edt Ses desee dee eo rn bie e EE oret E Rr ORE REN DP eere DER 40 D2 Scope Of pranta sa o ose e oec e EN eO dde erre ade aT 40 15 3 Disclaimer iecit Rr redet ras oe io E desine Od 40 D Consent z noe erret mei etre Latest 40 D5 Linguist Tools LICENSES x oot pte oot eor Eee eater ope Re e paved Dusk Nen QE ees Sox gro pue 40 DO Terminations a er RR ee NOE dades SE Da dee tes us 41 Index NR 42 Acknowledgment
19. First of all we would like to record a special credit to Vladim r Mencl whose paper 1 2 was the inspiration of this project Vladimir Mencl was also the supervisor of the project his councils friendly and patient attitude had a substantial influence on progress of the development Special thanks go to the Center for Computational Linguistics in particular to Prof Jan Hajic and Dr Jan Curin for the help with putting the linguistic tools together Also we would like to thank our friends and families for their support Foreword The Procasor project is a student Software Project at the Department of Software Engineering Faculty of Mathematics and Physics Charles University 1 The Procasor Team The Procasor team is the group of authors that cooperate on the development of the Procasor project Project Supervisor Vladimir Mencl lt mencl nenya ms mff cuni cz gt Team Members Michal Fiedler lt mfiedler centrum cz gt Jan Francu lt jenikff centrum cz gt Jiri Ondrusek lt gorduin seznam cz gt Ales Plsek lt aplsek gmail com gt Contact Information Procasor team Department of Software Engineering Faculty of Mathematics and Physics Charles University Malostranske namesti 25 11800 Prague 1 Czech Republic lt procasor nenya ms mff cuni cz gt http nenya ms mff cuni cz mencl procasor vi Chapter 1 Brief Overview Specifying requirements is the first step in the process of designing a software syst
20. MIS Seller SL Buyer BU Trade Commission TC and Credit Verification Agency CVA Except for MIS the most important one none of these entities contain its own use cases They are only actors Marketplace Information System contains several use cases describing cooperation of all mentioned entities In these use cases MIS acts as the system under discussion Looking closely on MIS we will see that MIS is not an atomic entity MIS is compound of three en tities Computer System CS Clerk CL and Supervisor SU All these entities contain their own use cases Let us focus on MIS and its use cases for now MIS involves seven use cases We will look at the first one Seller submits offer This use case describes the cooperation of the seller and the MIS primarily Therefore Seller is the primary actor of the use case The Trade Commission is involved as well it is a supporting actor of the use case The use case itself describes all actions necessary to submitting an offer We will take a closer look on the first step of this use case Seller submits item description The step is analyzed as a request receiving action Seller being the source of the request S1 submitltem Description was chosen as the token for this step Chapters 3 through 6 give detailed information on the step analysis while Section 8 4 2 describes the way analysis results are displayed The relation to the rest of the project is significant as well
21. Procasor Project User Documentation Procasor Project User Documentation Table of Contents Acknowledgment erroe to PORE RE A E EO ERES M OE EX VU ESAE pinta UAR UER V Foreword tad REID une e reni REI vi 1 The Procas r TeaM eer iere Re erar RR ER EERR goon REN PESE EEE PEIEE R REUS vi 1 Bref Overview ueniet In MD eS 1 Ld How To Use This Book i sc mt errem Er ERE ERES EEYR PS 1 2 Background AAA PER VERE REO EE 2 r E URA OE SIME 2 2 2 Specifying Component Behavior with Behavior Protocols Pro cases 3 2 3 Deriving Pro cases from Use Cases issis tarri rarene n EE ea EE emere 4 2 4 languistic Analysis A ecce ive ep yer ERE FE E Eee E Qe 4 3 The Procasot Project e iet eter rere re reb E Ser PEIPER RM EE RR 6 3 1 Writing Use Cases cote etre ts ts 6 3 2 Use Case step analysis ulises E I riada Area ee ETE ad 6 3 2 1 Constructing parse tree sisieun ie ior EE EEEE E ESAE 6 3 2 2 Parse tree analysis esie eerie AREER EEE TRUE EEE SEEE 8 3 2 3 Generating tokens 253 eee eile ether eire terre bees 8 3 3 Deriving behavior specifications from Use Cases sssse seca seen eeneens 8 3 3 1 Pro case generation oes oii sete ati 8 3 3 2 Model Pro case generation i ice Deer eee EEE RUER ier R Ernie 8 3 3 3 UML State Machine generation sssssseee cece cena cen eeneeeaeeeeees 8 4 Tanguistic tools applications ssiri senri reete Rt Er IRR ease sek na DE
22. R oboe es 10 4 T Introd ction 3 25555 Sos ertet reete En peteot eee eget epe e cett ep ed gutes te der iar ee get enge ds 10 4 2 Parse A E 10 4 3 Linguistic Tools Used e eene bec debs hene eripi ween 10 4 4 Usine Linguistic Tools siss 5 ot ves re b eR E Parte e tr eee EV RP pa 11 4 3 1 Imtialization ci e dee e ii 11 4 42 Linguistic Analysis 5 5 rm Ere GR ERE EE PREX TREE RS PRSE EE CERE RET ER 11 4 4 3 Restarting the Patser o sie eerte genre epi ree nadan side 12 4 4 4 Running stand alone linguistic tools coccoccocnocnncnoconcnnconcnnconcnnroncnnronos 12 5 Use Case Step Analysis css iro croata tii Reni ba eroe dette decori ter eet ee delta 13 3 1 Common Step Analysis iore opt e rte SIES LEUE ES TETERE eer EH 13 5 2 Detecting Special Actions sssssesseseee m eme me e e meer ree 14 5 3 Condition AnalYSiS ied be bte bebe taedet pee pa 14 6 Generating TOKENS cenit Ae 16 0 1 Prehmunaty son Dos ere WO er ROO AEEA E EEEIEE SIETE EEES a ERTS 16 6 2 Main steps of token generating process sssssssssss Hee 16 6 3 Manual Changes cuisine Ira IR ERE ER Ie ERe nates 17 6 4 How to manage tokens conti oirlo ee diete ente di Samed Wes o E Ung er Sones 17 7 Constructing Behavior Specifications sess He emere 19 7 1 Creating a Finite State Machine oooooccccccnccnnccnnccnnconnconnconnconnconnconncnnnnnnncnnncnaronoss 19 7 2 Creating a Pro case ete e tore POS D
23. The same action seller submits an offer is described from other point of view in the use case Clerk submits an offer on behalf of a Seller for the Computer System entity In this use case Marketplace Information System no longer is a black box Instead this use case describes the actions taken by the contained entities For example steps System validates the description and System lists the offer in published offers refer to the same actions Their tokens should be the same as you can verify C 3 Use Case List List of all use cases with actors follows Marketplace information System Acronym MIS Use cases e Seller submits offer Acronym MISI Primary actor Seller Supporting actor Trade Commission e Buyer searches for an offer 36 The Marketplace Project Acronym MIS2 Primary actor Buyer Buyer buys a selected item Acronym MIS3 Primary actor Buyer Supporting actor Seller Credit Verification Agency Seller cancels an offer Acronym MIS4 Primary actor Seller Seller checks on the status of an offer Acronym MIS5 Primary actor Seller Supporting actor Trade Commission Seller updates an offer Acronym MIS6 Primary actor Seller Supporting actor Trade Commission Buyer makes a purchase Acronym MIS7 Primary actor Buyer Supporting actor Seller Credit Verification Company Computer System Acronym CS Use cases Clerk submits an offer on behalf of a Seller Acronym CSI Pr
24. Use button applies the change The Write by hand section allows the user to write the whole token by hand 8 4 2 4 Pro case tab Create and displays the Pro case for the selected use case The Pro case is generated as described in Section 7 2 8 5 Properties Dialog From the Window menu or by pressing Ctrl T you can access the properties dialog The dialog is divided into four sections 28 User Interface 8 5 1 Editing Section Changes the behavior of the use case step tables e Automatic marking If the property is on the step mark of every new step is filled automatically and the step text column is automatically activated e Remarking This option can only be switched on if automatic marking is on Every time a step is inserted remarking solves possible conflicts among the step marks E g new step with mark 2 is inserted but there already is a step with the same mark The remarking algorithm automatically changes the conflicting step marks e Batch mode If batch mode is enabled every time enter is pressed in the second column of the use case table a new step following the selected one is created If batch mode is disabled first enter triggers the step analysis the second enter inserts a new step 8 5 2 Tokens Section This section allows you to change the properties of token generation The first option Number of tokens in listing window sets how many tokens you will see in windows in the To
25. ation is shown in the Parsed tree tab see Section 8 4 2 and you may change 1t there 3 2 3 Generating tokens The tokens are part of the action labels which are used instead of the whole sentences in Pro case generating process you can learn more about tokens and Pro cases in Section 2 2 Procasor generates the token from words marked in the parse tree analysis In addition the user may choose to use another token already used elsewhere in the project or to write the token by hand To learn more about this topic you can read the Chapter 6 where you will find more information on the token generating 3 3 Deriving behavior specifications from Use Cases Procasor provides two kinds of behavior specification Pro cases and UML State Machines You can derive behavior specification on various levels Pro cases and UML State Machines for single use cases model Pro cases for use case models or the complete set of UML State Machines for the whole project 3 3 1 Pro case generation Procasor can transform a use case into a Pro case defined in Section 2 2 For this transformation to be successful every step of the use case must have a valid semantic information You can create a Pro case by opening the Pro case tab in Pro case is a part of the text export of a use case and of the whole project as well 3 3 2 Model Pro case generation For a use case model Procasor can take its use case expression and replace use case acronyms with
26. ched only the matched words are used as the representative object Otherwise all nouns from this phrase are used For an example we will take the sentence System asks the Supervisor to validate the seller This sentence is a step of the use case called Clerk submits an offer on behalf of a Seller you can find this use case in the Marketplace project Computer system is the System under Design Clerk is the primary actor and Trade Commission Supervisor and Seller are supporting actors You can see the parse tree for this sentence in the following figure 13 Use Case Step Analysis Figure 5 1 Parse Tree Analysis Example Analysis of the sentence System asks the Supervisor to validate the seller Sentence asks Verb Phrase asks Sentence to a Noun Phrase System y Verb Phrase to to TO Verb Phrase validate asks VBZ Padding Verb validate VB Main Verb Noun Phrase Supervisor Noun Phrase seller System NNP the DT Supervisor NNP the DT seller NN PUNC Subject Indirect Object Representative Object The word System is the subject of this sentence It is a keyword referring to the SuD Because SuD is the subject of the sentence we search for an indirect object We inspect two phrases the Supervisor and the seller and detect that Supervisor is the indirect object of the sentence From this information we conclude that this step represents a request sending action Afterwards we identify the
27. ct e Mix the words in the sentence to compose the token e Write the token by hand User can write similar sentences for the same action but the slight difference may still lead to creating different tokens Therefore the user can change the selected token in one of these ways Merging the token with another token used in the project let the user keep the tokens in project consistent By consistence we mean that in the project the steps that refer to the same action should have the same selected token The second way of manually changing the selected token is mixing the token from words contained in the step s sentence This is useful in the situation when the words used in the selected token are not in the proper order The selected token may contain some words which the user does not want to be used in selected token or the selected token does not contain some important word which user wants to use in the selected token The third way is to write the token by hand This should be the least common way of changing the selected token There is no need to keep tokens short instead the token should contain enough inform ation about the action to which it refers to The use case sentence contains the description of the action and therefore the selected token contains the description of the action too But in some unpredictable cases could Procasor s analysis fail and then user can write the token by hand This option may also come useful when yo
28. d beside the terms UML Unified Modeling Language entity diagrams scenario and many others In this chapter we provide a gentle introduction into the use cases topics mainly focused on the topics which are related to the Procasor program For more complex information about UML and use cases we recommend an excellent book by A Cockburn Writing Effective Use Cases 3 and the UML website 4 If you are familiar with use cases and UML you can skip this chapter but we suggest you read it The use cases are a set of documents which are usually written when the requirement specification is gathered The described system System under design SuD will perform some tasks In this process the system communicates with other entities actors and other components When performing the task the system follows a scenario For each task we write a use cases to record the sequences of actions performed during the task First we decide which entities will act in the use case we record them as the actors of the use case Then we write down the sequence of actions performed in case of successful execution of the task We call this sequence the main success scenario The individual actions are called use case steps We give every step a number according to its position in the sequence we call this number a step label In addition we collect branches that reflect possible diversions from the typical task execution For every branch we define at which ste
29. d conflict Conflict can be solved in Analysis tab Section 8 4 2 2 where you can choose between the newly generated result and the last manually changed result Button located in the fourth column create new steps extending the selected step e g for step 1 new step la is created in the lower table You can navigate through these tables by pressing up and down arrow keys Pressing enter triggers various actions depending on the Batch mode setting Section 8 5 Use case popup menu Figure 8 5 is displayed when right clicking on a step table Figure 8 5 Use case popup menu Add new use cas step Remove Move up Move down Analyze step Reanalyze all steps Remark all steps Goto target gt Includ use case gt Import steps from file Export use case to txt Export use case to UML e Add new use case step Inserts a new empty step at the selected position e Remove Removes the selected step e Move up Moves the selected step one row above e Move down Moves the selected step one row below Analyse step Starts analysis of the step e Solve conflict Shows Analysis tab Section 8 4 2 2 where conflicts are resolved Analyse unanalysed steps Requests analysis of all unanalysed steps of the use case e Reanalyse all steps Requests analysis of all steps of the use case e Discard manual changes Discards manual changes performed in the result and use the generated
30. d of the branch is connected to the beginning of the event following the parent event giving command back to the upper level Branches may be connected to multiple parents In that case a special copy of the branches states and transitions is made for every parent Special actions do not represent an event and must be transformed differently Termination and goto actions are represented as transitions to the relevant state Include use case action results in creating another finite state machine using the same method and connecting it to the surrounding states In addition if this use case including step has a special variation of type Handles included use case failure the included use case remembers this variation as its abort handler Abort action works the same as termination action if not inside an included use case If there is an abort action inside an included use case another transition is created This transition connects the in cluded use case and its abort handler and bears the value of the condition event that triggered the abort action If the included use case has no abort handler the transition is connected to the parent machine s final state and the same is repeated until an abort handler is reached or untli we reach the topmost FSM Following figure shows a state machine for the use case Seller submits offer You can see the original use case in the Figure 2 1 19 Constructing Behavior Specifications Fig
31. e A step is added to the branch Enter Use case aborts as the text of the step This time a special action is detected as desired B 5 Generating Behavior Specification When all steps of the use case have been entered and analysed and each step has its token Pro case can be shown A Pro case for the use case is displayed in the Pro case tab in the Use case window Example The Pro case for the Seller submits an offer use case from the examples above is SL submitItemDescription NULL itemInvalid To receive the global behavior of the described entity you have to set its model expression To do this go back to the Project window and press the Edit button in the Model section There you can enter the model expression manually or using the Expression editor Example Select the MIS entity and press the Edit button in the Model section In the Model expression field enter UC1 UC1 This expression describes the behavior of the Marketplace Information System as two consequent runs of the use case Seller submits an offer Now you can display the Pro case describing global behavior of the MIS entity by pressing the Pro case button in the Model section of the Project window In addition you may export the project to UML or to a text file 34 Appendix C The Marketplace Project C 1 Opening the Project This chapter will introduce you to the example project Marketplace which is supplied with the Proc asor installatio
32. em or a component For the task of such specification use cases written in natural language are usually used While this method provides a gentle and swift way of creating an easily readable specification use cases written in natural language can not be used in reasoning on requirement specification or employing the use cases in deriving an initial design in an automated way Although the use cases contain a huge amount of relevant information about software system or component being specified it is difficult to obtain a precise formal specification for it is expressed in natural language The Procasor project attempts to harmonize the creation of requirement specifications employing use cases with creation of precise formal specifications of a software system or a component To meet this goal the Procasor includes an interactive environment which provides a comfortable development of a use case model and also the generation of a precise formal specification Moreover Procasor allows to develop natural language use case model and precise formal specification at the same time which demands only slightly increased effort required to write the use case model Procasor includes Linguistic analysis algorithms which employ integrated linguistic tools in order to analyse use cases We implement the construction of behavior specifications in two notations Beha vior Protocols and UML State Machines Procasor incorporates an interactive environment that prov
33. escription Sentence submits Noun Phrase Seller Verb Phrase submits Noun Phrase description A A Seller NNP Seller submits VBZ LM item NN item description NN description 4 3 Linguistic Tools Used Obtaining the lemma and determining the POS tag of a word along with acquiring a parse tree from a sentence are key tasks of linguistic analysis employed in Procasor 10 Linguistic tools application To meet these requirements Procasor employs the linguistic tools which cooperate on analyzing the sentence e Tokenizer Tokenizer is used for preprocessing of the sentence before it is passed to tagger e MXPost tagger The third tool is MXPost tagger we use the tagger for assigning POS tags e Collins parser The key linguistic tool employed in Procasor is the Collins parser It is a statistical parser developed by M Collins at the University of Pennsylvania and we use this tool for obtaining a parse tree of the sentence Collins parser was chosen for its high accuracy and for the robustness of its parsing algorithm However integration of this tool increases hardware requirements and specially initial ization process is time demanding The user should have at least 200MB of free memory to run the parser e Morph a tool Morph a tool is a morphological tool developed at the University of Sussex to obtain the lemma base form of a word 4 4 Using Linguistic Tools 4 4 1 4 4 2 Although the applicatio
34. extension e Save as To save the active project into a different file e Rename To change the name of the project e Export project to txt To open the exporting window The exporting window contains the textual export of the project This textual export can be modified and saved to a file e Export project to UML To export the project information to UML Section 7 4 and save it in the chosen file e Close Ctrl X To close Procasor Closing Procasor also terminates linguistic tools if they are running or starting Parser menu Parser menu controls states of linguistic tools 22 User Interface e Start parser To start linguistic tools When starting linguistic tools all sentences waiting for analysis are removed from queue Look at Section 8 4 1 for more information about queue e Close parser To stop linguistic tools e Restart parser To restart linguistic tools Show parser console To show the Parser console Section 8 2 2 2 e Close parser console To close the Parser console Section 8 2 2 2 Window menu Show hierarchy Ctrl H To show the Hierarchy panel Section 8 7 Show token manager Ctrl K To show the Token manager window Section 8 6 e Properties Ctrl T To show Properties window Section 8 5 About menu To show the basic facts about the Procasor project 8 2 2 Linguistic Tools Control Centre In following text the group of linguistic tools wi
35. ides user feedback during the process of the precise formal specification development 1 1 How To Use This Book The goal of this book is to introduce all the features provided by Procasor To reflect the goal the book 1s organized as follows In the Background chapter Chapter 2 we provide an explanation of the basic ideas and problems which are important to be understood before using Procasor The Procasor project chapter Chapter 3 introduces all the ways the application can be used This chapter is essential for understanding what the Procasor project can offer to the user Chapters Linguistic tools application Chapter 4 Use Case Step Analysis Chapter 5 Generating Token Chapter 6 and Constructing behavior specifications Chapter 7 explain individual parts of Procasor in detail User Interface Chapter 8 describes features of the Procasor environment Installation manual can be found in Appendix A Before the user starts using Procasor we recommend to read chapters Getting started Appendix B and MarketPlace Project Example Appendix C as well These chapters provide basic suggestions for working with Procasor and demonstrate functionality of Procasor on the Marketplace project example included in the Procasor distribution For better orientation in this document we provide also the Index Appendix B Chapter 2 Background 2 1 Use Cases The use case is the term in the software engineering which is use
36. imary actor Clerk Supporting actor Trade Commission Supervisor Buyer searches for an offer Acronym CS2 Primary actor Buyer Clerk buys a selected item on behalf of a Buyer 37 The Marketplace Project Acronym CS3 Primary actor Clerk Supporting actor Seller Credit Verification Agency Seller cancels an offer Acronym CS4 Primary actor Seller Seller checks on the status of the offer Acronym MIS5 Primary actor Seller Supporting actor Trade Commission Seller updates an offer Acronym CS6 Buyer makes a purchase Acronym CS7 Primary actor Buyer Supporting actor Seller Credit Verification Company Supervisor makes an internal audit Acronym CS8 Primary actor Supervisor Clerk Acronym CL Use cases Seller to Clerk Acronym CL1 Primary actor Seller Supporting actor Computer System Buyer to Clerk Acronym CL2 Primary actor Buyer Supporting actor Computer System Supervisor Acronym SU 38 The Marketplace Project Use cases Supervisor validates a seller Acronym SUI Primary actor Computer System Supervisor performs internal audit Acronym Su2 Primary actor Computer System 39 Appendix D License The Procasor project is copyright c 2005 Procasor team Section 1 D 1 License information The Procasor team Section 1 Owner grants to the individual researcher who install this software Licensee a non exclusive non transferable
37. ing the token These are the main verb and the representative object The example sentence Seller submits item description is analyzed as request receive action and the marked words are Seller noun SuD e submits verb main verb item noun word which is important and should be used for building token description noun word which is important and should be used for building token 6 2 Main steps of token generating process The whole token management process consists of three steps e Simple generating first simple token generating the product of generating process is a simple token Learning process token customization based on other tokens the product of learning process is a learned token Manual changes performed by user the product of manual changes is the manual token Usual scenario should only employ simple generating described with an example in next paragraph If there already is a similar token in the active project we analyze this similar token and try to build the new token according to the analyzed information The similarity rate can be set by the user in the Percents of similarity to perform token learning setting This newly build token we call the learned token and this process the Learning process If the information is sufficient for building the learned token then the learned token is used instead of the simple token More information about the learning process is in Developer Docu
38. is replaced by a Pro case generated from the relevant use case 7 4 Creating a UML State Machine For the UML State Machine we compute states positions in the diagram Generated UML document contains a UML State Machine with its states transitions diagram layout information and UML class entry for the entity that owns the original use case If you choose to export the whole project to UML the resulting document will contain classes for all entities and state machines for all use cases The UML document is saved in the XMI format which is an XML notation for writing UML documents You may open and edit this UML model using your favorite UML modelling tool we recommend the Poseidon tool 13 20 Constructing Behavior Specifications Figure 7 2 Pro case Example Resulting Pro case for the use case Seller submits offer Sl submitItemDescription validateDescription itemNot Valid 2S1 submitltemDescription assessmentAvailable ISI provideAssessment 2S1 submitltemDescription validateDescription Sl adjust validateSeller ISI verifySeller TC validateOffer NULL tradeCommissionRejectsOffer listOffer respondAuthorizationNumber sellerHistoryInappropriate 21 Chapter 8 User Interface 8 1 Introduction This chapter provides an overview of Procasor graphical user interface Especially non obvious features resulting from generally recommended rules for writing use cases
39. ken panel Sec tion 8 4 2 3 The second option Percents of similarity to perform token learning influences token generation see Chapter 6 or the Developer documentation for details 8 5 3 Parser Section If the Start parser in start up option is enabled linguistic tools are automatically started at application s start up 8 5 4 Auto Save Section Sets how often the opened project is saved Time is set in minutes Value 0 means project will not be saved automatically 8 6 Token Manager Window This window displays all tokens present in the project Every token can be manually modified if the action type is condition request receiving request sending internal or unknown From a popup menu you can choose another token to be merged with the active one If the modified token is used in multiple steps you will be asked whether all tokens with the same token should be modified 8 7 Hierarchy of Entities Window This window displays hierarchical relations between entities 8 8 Importing Use Cases Procasor provides simple importing into the use cases Importing is accessible from popup menu in Use case table Section 8 4 1 Importing allows to import steps into the use case Text files step are imported from have to be in specified format Each line corresponds with one step First word of the line is used as a step mark the rest of the line is used as a text for the step 29 Bibliography Reference
40. ll be called Parser Linguistic Tools Control Centre is shown in Figure 8 1 In the right lower corner there is the Parser progress bar Progress bar displays the state of the parser e Green bar Parser is running Red bar Parser is closed Progress bar with percentage description Parser is starting Clicking the bar with right button brings up parser popup menu left clicking displays the Parser console Figure 8 1 Parser console screenshot Parser consol Initialization of the PipeLine Starting Tokenizer tool Btarting MXPostTagger tool Starting Collins Parser tool starting MorphA tool Tokenizer started properly MorphA started properly MXPostTagger started properly O Tokenizer mxPost Tagger Collins parser Morpha Parser console 23 User Interface 8 2 2 1 Parser Popup Menu Parser popup menu allows you to start or close parser and brings Parser console The parser popup menu has the same items as the Parser menu in the Section 8 2 1 8 2 2 2 Parser Console Parser console displays information messages sent by linguistic tools and shows states of each tool separately The main part of the console is the section in which linguistic tools messages are displayed Individual linguistic tool messages are described in Developer documentation in detail At the bottom of the Parser console there are four icons that represent the states of linguistic tools
41. ls used in Procasor 4 2 Parse Tree Results of linguistic analysis are stored in a structure called parse tree The parse tree of a natural lan guage sentence captures the structure of the sentence according to the grammar of the respective nat ural language English in this case Leaves of the tree reflect the words of the sentence in left right order while intermediary nodes represent phrases Figure 4 1 shows the parse tree obtained for sentence Seller submits item description Each intermediary node represents a phrase formed by words in its leaves Information involved in this node consists of type of the phrase and the headword of the represented phrase E g in Figure 4 1 the nouns item and description constitute a noun phrase denoted NPB which together with the verb submits form a verb phrase VP The headword representing the verb phrase is submits While intermediary nodes represents phrases leaves reflect the words of the sentence Each leaf responds to a word contained in the sentence Leaf also includes additional information about the word it repres ents POS tag and lemma POS tag part of speech tag determines the word type and the role it plays in the phrase structure Lemma is the base form of the word E g in Fig 1 the POS tag of submits is VBZ verb in the s form item and description are nouns NN Lemma of submits is submit Figure 4 1 Parse tree for sentence Seller submits item d
42. mentation in the section Token Generation in subsection Learning token The simple token generating process concatenate words marked as important for building token The words are concatenated in the order in which they were used in the sentence For example the simple Generating Tokens token generating process produce for the sentence Seller submits item description following action label type of action sentence action is analysed as request receive action SL actor acronym of the entity Seller which was marked as subject the dot which separate the actor and the token submitItemDescritption token concatenated words which were marked as important for building token The learning process will be illustrated on another example sentence Let the action label with token SL propertiesSet be already used in the project and you are writing the sentence Seller get the properties Then you can expect the action label with token SL propertiesGet but the simple gen erating process produce action label with token SL getProperties If the token propertiesSet from the action label already used in the project is similar to the token from the actual sentence getProperies Then the process of learning token is applied and produce token SL propertiesGet 6 3 Manual changes If the user is not satisfied with the selected token there are three ways of changing the token e Merge the token with another token from the proje
43. n Use cases in the market Marketplace project are extracted from 12 To open the project simply press Ctrl O or select Open from the Project menu Choose Market place pro file with the project in the dialog with file listing and click Open Project window will appear shown in Figure C 1 Figure C 1 Main window screenshot PROCASOR exatmpleFroJect Project Parser Window Help PROJECT Marketplace Description his is an example project for Procasor tool This example is belongs to supplied instalation Entities Entity Marketplace Marketplace Information System eller rade Commision Buyer Credit Verification Agency Computer System Model default Seller submits offer Buyer searches for an offer Buyer buys a selected item Seller cancels an offer Seller checks on the status of an offer Seller updates an offer Buyer makes a purchase Add Delete l PROJECT Marketplace Parser is running C 2 Description Our example describes marketplace with its most important entities and basic actions In Figure C 2 you can see the diagram of all entities 35 The Marketplace Project Figure C 2 Hierarchy of entities Marketplace Buyer Credit Verification Agency Marketplace Information System Clerk Seller Computer System Trade Commision Supervisor The main entity is the entire Marketplace which contains Marketplace Information System
44. n of linguistic tools is managed automatically we introduce some basic issues concerning usage of this tools in this chapter We describe the initialization and parsing processes of linguistic tools visible for the user and provide the information about error situations and their solutions For more details please see the Developer s documentation Initialization As mentioned in Section 4 3 the initialization process of linguistic tools is time demanding and therefore using of this tools could be uncomfortable Initialization of the Collins parser is very slow in particular We solve this problem by running initialization processes in background which provides the opportunity to use the application without the need to wait until linguistic tools initialization is completed Linguistic Analysis Linguistic analysis is a part of use case analysis and therefore the user does not have to maintain pro cesses which take part in sentence processing The results acquired from linguistic tools are automat ically collected and passed in the form of a parse tree which is displayed graphically User is informed about particular steps of linguistic analysis by short messages which are displayed in the Parser Console The part of the application which provides the parse tree generation is called the Parser The Parser is represented on the user s screen by the Parser Console Section 8 2 2 2 The Parser console shows messages describing the status of the
45. nd email with appended log file to the Procasor team Section 1 The log messages are appended to the logs pipeLine log file detailed information about this log file and its structure is available in the Developer documentation Running stand alone linguistic tools The distribution of Procasor contains all linguistic tools used by Procasor In addition we provide the opportunity to use linguistic tools that are not part of our application For example the user can run the Collins parser which has been installed to a detached location and is not part of Procasor distribution For details about this option please see the chapter about the Configuration file in the Developer documentation 12 Chapter 5 Use Case Step Analysis Common step analysis is applied on common non condition steps If common step analysis is not successful we try to detect a special action Condition analysis is applied on branch triggering condi tions 5 1 Common Step Analysis For a common step the semantic information is derived as follows First we detect the subject A sentence conforming to the SVDPI subject verb direct object pre position indirect object pattern should contain a noun phrase and a verb phrase This main noun phrase is the subject As the subject has to be an entity we match nouns in the subject phrase with names of actors involved in this use case Moreover term System may refer to SuD and term User refers to the
46. no subject A sentence containing a goto action mostly has no subject so we do not even try to identify it Instead on we search the sentence for a verb from a keyword list resume continue etc and for a step label A word is identified as a step label if it starts and ends with a digit 5 3 Condition Analysis When analysing a condition we only decide whether each word is important and thus should become part of the condition s token The word is only marked as not important if it s one of the following apreposition e punctuation 14 Use Case Step Analysis a to word e determiner any or the apadding verb Otherwise the word is considered important and will be used for creating the token of the condition 15 Chapter 6 Generating Tokens This chapter will give you a deeper look inside the management of the token generating process In the token generation and management we work with several terms which are crucial to understand the whole topic Action label label containing step s information about type of the action the actor token selected token token which will be used for generating the Pro case 6 1 Preliminary The tokens and action labels are generated from the information provided by the tree analysis and linguistic analysis From previous analysis we already know the type of the action subject or and in direct object and the words which should be used for build
47. ociation for Computational Lin guistics 24 27 June 1996 University of California Santa Cruz California USA Proceedings Morgan Kaufmann Publishers Copyright O 1996 9 Morph A tool http www informatics susx ac uk research nlp carroll morph html 10 Tokenizer http www clsp jhu edu ws99 projects mt toolkit 11 Theory of Automata lecture notes http kti mff cuni cz bartak automaty index html Roman Bartak 12 Frantisek Plasil and Vladimir Mencl Use Cases Assembling Whole Picture Behavior TR 02 11 Dept of Computer Science University ofNew Hampshire Durham Copyright O 2002 13 Poseidon UML modelling tool http gentleware com 30 Appendix A Installation Manual A 1 Requirements and Prerequisites Procasor is a program developed for Linux platform written in the Java programming language Procasor is integrating highly sophisticated linguistic tools which increase hardware requirements These requirements for running the application can be summarized as follows Linux OS kernel 2 2 or above libc 6 or above e Java tm runtime 1 4 or above 1 4 1 or above highly recommended e Perl version 4 or above installed as usr bin perl e Atleast 300MB of free memory e 350MB of free disk space Procasor has been tested and validated on the following platforms Fedora Core 2 4 Gentoo Linux 2005 1 Mandrake 10 The application was developed on Java 1 4 mainly on 1 4 2 06 Although we
48. p of the main scenario the branch starts We write down a condition which describes the difference from the typical execution Thereafter we record the actions executed when the condition holds true we call them branch steps The condition gets a label consisting of the extended step label and a letter e g 2a the branch steps append an ordinal number to the step label of the condition e g 2a1 We distinguish two types of branches extensions and variations Extensions represent actions performed in addition to the extended step while variations are executed instead of the step A branch can be attached to more steps than only one The steps can be specified by a range the step label being e g 2 6a All steps in main scenario can be represented by an asterisk the step label being e g a As an example we will take a Marketplace Information system managing buying and selling the goods With a use case we will model the process that allows the user Seller to enter some item on market The main scenario of this use case will contain describing the item description validation entering the price and contact and validation of the contact and verification users history and validation of the offer with Trade Commission Then the system lists the offer and responds with unique authorization number The step of validation of item s description will have an extension saying that if the user wants to insert an item which is not permited on this
49. primary actor of the use case If subject is not found we try to detect a special action If the step is not even a special action the tree analysis fails Possible reasons are that the sentence was either badly written or that the linguistic tools have failed If SuD is the subject we check whether an actor is the indirect object of the sentence We consider all noun phrase subordinate to the main verb phrase to be indirect object candidates For every candidate all included nouns are gathered and matched with actor names We do not allow the indirect object to be in possessive case If SuD is the subject and indirect object is found the step describes a request sent by SuD to the indirect object actor If indirect object is not found the step is an internal action If an actor is the subject the step describes receiving a request from this actor from the view of SuD The main verb is the first full verb verb that carries the meaning in the main verb phrase If the first verb is a padding verb one of ask be decide to etc and there s another verb following it we use the second verb Otherwise the first verb is recognized as the principal verb Excluding phrases used for subject and indirect object the first basic noun phrase subordinate to the main verb phrase is identified as the indirect object All nouns from this phrase are collected and matched with the conceptual object list If a name of some conceptual object is mat
50. s 1 Vladimir Mencl Deriving Behavior Specifications from Textual Use Cases Proceedings of Workshop on In telligent Technologies for Software Engineering WITSE04 Sep 21 2004 part of ASE 2004 Linz Austria ISBN 3 85403 180 7 pp 331 341 Oesterreichische Computer Gesellschaft Copyright O 2004 2 Frantisek Plasil and Vladimir Mencl Getting Whole Picture Behavior in a Use Case Model in Transactions of the SDPS Journal of Integrated Design and Process Science vol 7 no 4 pp 63 79 Dec 2003 Copyright O 2003 10920617 3 Alistair Cockburn Copyright O 2001 Addison Wesley 0201702258 Addison Wesley Professional 1st edition January 15 2000 Writing effective use cases 270 4 http www uml org 5 Frantisek Plasil and Stanislav Visnovsky Behavior Protocols for Software Components IEEE Trans Software Eng 28 11 Copyright O 2002 6 M Mach and Frantisek Plasil Addressing State Explosion in Behavior Protocol Verification Proceedings of SNPD 04 Beijing China Copyright O 2004 7 A Maximum Entropy Part Of Speech Tagger http www cis upenn edu adwait statnlp html Adwait Rat naparkhi In Proceedings of the Empirical Methods in Natural Language Processing Conference May 17 18 1996 University of Pennsylvania Copyright 1996 8 A New Statistical Parser Based on Bigram Lexical Dependencies http www cis upenn edu mcollins Michael Collins ACL 1996 184 191 34th Annual Meetingof the Ass
51. se case sequences see Chapter 3 For easier creating of use case expressions the Expression editor is provided Editor allows only allows to insert valid symbols and acronyms by clicking appropriate buttons Figure 8 3 24 User Interface Figure 8 2 Project window screenshot PROCASOR exampleProject Project Parser Window Help PROJECT Marketplace Description E E objects item his is an example project for Procasor tool This example is belongs to supplied instalation Marketplace Information System eller rade Commision Buyer Credit Verification Agency Model default Seller submits offer Buyer searches for an offer Buyer buys a selected item Seller cancels an offer Seller checks on the status of an offer Seller updates an offer Buyer makes a purchase i 4 Add Delete PROJECT Marketplace Parser is running Figure 8 3 Expression editor Expression editor MISI MIS4 MISS MIS6 MIS7 JEJE EIS PIED If model expression for the active use case model is valid the Pro case button displays a window with generated model Pro case The model Pro case can be modified and saved to a file 8 3 3 Use Case Management Use cases are displayed in the lower part of the Project window When adding or editing a use case name and acronym have to be filled Acronyms have to fulfil the same conditions as model acronyms They have to
52. source of this event and that token of this event is submitltem Background Operators can be used to combine expressions into composite expressions Among the operators are for repetition for optionality for sequencing for alternative for and parallel execution Il for or parallel execution A ll B meaning A B AIB Other operators are not supported by Procasor A Pro case being an expression created in this manner forms a regular language There is a verifier tool available 6 for checking consistency of Pro cases 2 3 Deriving Pro cases from Use Cases In 2 F Plasil and V Mencl proposed a manual transformation from textual use cases into Pro cases In his subsequent work 1 V Mencl presented a method for automation of this transformation Transformation performed in this project is based on both of these proposals This transformation builds on two premises quote from 2 Premise 1 A step of a textual use case describes either a communication between an actor and SuD a request being sent or information passed or b an internal action Premise 2 Such action is described by a simple English sentence following a uniform pattern end of quote To specify the Premise 2 more precisely the sentence should follow the SVDPI subject verb direct object preposition indirect object pattern These premises guarantee that we can identify the entity actor or SuD that is the subject of
53. terms of this License Ownership of the Software shall remain solely with the Owner D 5 Linguistic Tools Licenses The distribution of the Procasor project contains linguistic tools which are stand alone applications with their own licenses Before using the Procasor please read carefully licences of linguistic tools which can be found in the tools directory Section A 3 40 License D 6 Termination The Owner shall have the right to terminate this license at any time by a written notice Licensee shall be liable for any infringement or damages resulting from Licensee s failure to abide by the terms of this License 41 Index A Actor 2 Branch step 2 6 19 E Enity 6 definition 2 Entity 13 16 24 29 hierarchy 3 Extensions 2 L Linguistic tools 4 6 23 40 P Parse tree 4 6 Parsed tree 28 Pro case 3 4 8 8 19 34 S Successful scenario 2 SuD 2 13 16 T Token 8 16 28 29 29 U Use case 24 33 definition 2 example 3 writing in Procasor 6 Use case expression 6 24 Use case expressions 3 Use case model 6 8 20 24 Use case step 2 6 19 V Variations 2 42
54. the sentence Optionally we identify the entity that is the indirect object of the sentence From this inform ation we can conclude whether the step describes an event emitted absorbed or internally processed Premise 2 alone warrants that we can locate the main verb of the sentence and its representative object We get the event token for this sentence by combining the verb and the representative object Now that we have the action type active entity and the event token we can combine them into an atomic event of a Pro case We connect subsequent steps this connection is reflected by the sequencing n n operator in the resulting Pro case Extensions and variations or branches for short are connected to the main success scenario this connection is reflected by the alternative operator in the resulting Pro case We obtain an event token for the condition triggering the branch Pro cases do not support conditions so we represent the condition with a special internal event We use this condition event as the first event of the branch The semantics is that this condition event and following events of the branch can only be processed when the condition is fulfilled There s an important exception to the premises above Special actions do not describe a communication neither do they describe an internal action They change the flow of control in the use case and this has to be reflected in the resulting Pro case Among others
55. tion goes In case of branch triggering conditions you should not describe what happened but what exactly the designed system detects You can read more about effective use case writing in 3 Use case model has a use case expression This expression uses syntax described in Section 2 2 This expression has to be set if you want to generate a model Pro case 6 If you write use cases following these instructions then you can get meaningful Pro cases But if you will not guard these instructions using this program could be wasting of your time 3 2 Use Case step analysis When a step is entered it is analysed in order to obtain its semantic information 3 2 1 Constructing parse tree Constructing parse tree is the first step of the linguistic analysis employed in Procasor Section 2 4 Parse tree Section 4 2 is constructed by the integrated linguistic tools Section 4 3 The parse tree The Procasor project Figure 3 1 The Procasor project engineering process model LEGEND Review problem brainstorm Learn controlled language user action use cases identify viewpoints for writing use cases L Procasor implementation 1 WRITING 7 For every use case choose actors and their respective roles Enter use case Enter use case Enter use case description 1 description 2 description n 2 USE CASE STEP ANALYSIS 2 1 Linguistic tools application ParseTree construction 2 2 Determining action type and entities in
56. ts and use cases from Procasor Recommended directory for importing use case steps to Procasor Contains the jar files used for running the application externals Contains external jar used for running Procasor procasor jar Procasor project jar file Contains log files of the application Directory used for saving the projects marketplace pro Example project for demonstrating Procasor functionality Contains the source code for Procasor Contains the directories in which the linguistic tools used in Procasor are stored CollinsParser morph MXPost tagger Tokenizer 32 Appendix B Getting started B 1 Creating a New Project To create a new project simply press Ctrl N or select New in Project menu from the main menu A window for setting the name and description for the project appears After filling the name and or description press the Use button Project window Section 8 3 appears Example Create a new project called Simple Marketplace B 2 Adding Entities Start with adding entities Button Add in the box Entity displays a window for creation of entities Section 8 3 1 Remember the name and the acronym of the entity have to be filled Example To create Marketplace Information System simply fill Marketplace Information System in the Name field and MIS in the Acronym field Press the Save button Create another entity Seller SL in the same manner B 3 Creating a Use Case
57. u can t run the parser for some reason 6 4 How to manage tokens This section gives you the meaning how to use token generating process for you purpose The details how you can do it you can find in chapter User interface Chapter 8 When you have written and parsed the sentence the selected token is generated and displayed First is generated the simple token If the generation of learned token success the learned token is used as selected instead of simple token In some cases the simple token generation fails This is due to fact that some required information were unprovided by previous analysis In this case is better to reformulate the sentence and parse it again and if it does not help then you can change token manually 17 Generating Tokens If you are not satisfied with the selected token or the Procasor s analysis fails you could change token manually Section 6 3 Mainly in the beginning of the project modeling process you may correct the order of the words used in selected token by mixing them together When you have several use cases written in the project then the amount of the selected token have populated Then you may use token merging to ensure that the same action should have same selected token in all use cases Chapter 7 Constructing Behavior Specifications Procasor provides derivation of two kinds of behavior specification You can choose between Pro cases and UML State Machines When deriving behavior
58. ult of the linguistic and tree analysis Nodes in the upper part represent phrases of the sentence leafs correspond to the words of the sentence Roles of words can be changed If you change the role of a word you will be offered regenerating the token Grey color of the tree means that manual changes were made and changing the words role would have no effect Above the tree there is a list box for changing the action type Some step types e g request sending goto offer a second list box for selecting the acting entity or the target step Action type cannot be changed in steps marked as Condition and no other step can be mark as Condition unless it is a condition that triggers an extension or variation The topmost box shows the action label for the step 8 4 2 3 Token Tab Token tab enables the user to change the token You can read more about token management in Chapter 6 In the upper part the current action label is displayed Below there are three sections each for a different type of token changing You should know that only tokens of Condition Request re ceiving Request sending Internal action and Unknown steps can be modified The Merging section allows you to choose from offered tokens Button All tokens displays a dialog with the list of all tokens used in the project Click use to merge the token with the selected one The Mixing section allows you to choose which words will be used and in which order The
59. ure 7 1 State Machine Example State machine for the use case Seller submits offer e nitial post_2 post_2 e_1 E E stitemNotValid pre pre 2a1 SI submititemDescription pre 221 post 1 validateDescription Bost pre3 Y pe3 pre 2 Sl adydst pe2 posta pre 6 assessmentAvailable gt post3 pee 7j pre 2b1 ITC vakdateOffer pre 2b B pre 4 post 6 ISI provideAssessment pre 4 post 6 post 2b1 validateSeller ftradeCammissionRejectsOffer post 2b1 post 4 pre_7 posts pre 7 MistOffer pres post 7 pre 5 J post_7 SL verifySeller T Y pre_8 post_5 Prez 5 pre 8 respondAuth orizationNumber sellerHistorylnappropriate s pre_5ai post 8 pre Sal post 8 de final 7 2 Creating a Pro case To acquire a Pro case from the previously generated finite state machine we employ the algorithm for deriving an equivalent regular expression described in 11 If there are any included machines we process them at first using the same algorithm After processing them we replace the FSM by two states and a transition with a value set to the derived expression Pro cases derived in this manner only use several expression operators alternative repetition sequence 7 3 Creating a Model Pro case In order to generate the model procase we parse the use case expression Operators and brackets are indented to preserve readability When a use case acronym is encountered it
60. volved Parse tree analysis Editing 2 3 Token construction Token generation Token merging Writing token by hand 3 DERIVING BEHAVIOR SPECIFICATIONS 3 1 Finite state machine Creating finite state machine 3 2 Deriving UML state machine 3 3 Pro case generation diagram 3 4 Behavior protocol derivation Behavior protocol derivation Editing The Procasor project obtained for every use case step is used by following processes of the use case step analysis in order to acquire required information about the action type of the analysed step In the process of parse tree construction no user interaction is required the result of linguistic tools application is shown in the Parsed tree tab Section 8 4 2 3 2 2 Parse tree analysis Based on the parse tree and additional information actors conceptual objects program determines semantic information included in the sentence This semantic information includes the action type described in Section 2 2 entities involved in this sentence the main verb and words that form the indirect object of the sentence For special actions semantic information can contain another entries For ordinary actions request receiving or sending internal actions involved entities names main verb and indirect object will be used to create the token of this sentence For special actions this se mantic information will be used in the Pro case construction Derived semantic inform
61. when deriving information from sentences Unlike entities conceptual objects only act as names or symbols not described objects For example if you are modeling a system for post office then conceptual objects could be letter package telegraph and others Now when you have written down all the conceptual objects and entities you are almost prepared for writing use cases Use cases are grouped into use case models every entity may have one or more models The models are useful in a situation when you want to describe the entities behavior from different points of view Usually you will only need one model Procasor creates a default use case model for every entity Once you have selected the model you can create the use case The created use case always belongs to certain entity this entity is called the System under Design or SuD for short Then you need to mark the entity which will act as the primary actor in the use case Optionally you can mark entities that will take part as secondary actors The primary or secondary actor is the entity which is involved in the actions which are described in the use case When you have created the use case you can write sentences as use case steps or as branch steps A rule applies here you should keep the sentences simple and unambiguous so that it is clear what happens in the step Moreover readers should understand where the ball goes which entities are involved and in which way the communica
62. ype Y 2a Item not valid extension Y pal Use case aborts Y 2b Price assessment available variation v 2b1 System provides the seller with a v 5a Seller s history inappropriate extension Y Sal Use case aborts wv ba Trade commision available extension x tur Y Down 3 Add X Delete la D Use Case Tables Two tables are situated here The first table serves for writing steps of the main scenario second table contains extension and sub variation steps of the use case The behavior of these tables depends on the current settings of Procasor See Section 8 5 for detail The first column of the tables displays the state of the analysis for the sentence Possible states are e New sentence Y Correctly analysed sentence Y Sentence waiting for analysis The sentence was sent to the parser e XK Analysis failed for this sentence Y Sentence has a conflict See below Star appears next to the symbol if the text has just been changed The second column contains step marks Red box around the field means that something with the step mark is wrong Keep the cursor upon the field to see a tooltip message with detailed explanation The third column contains the step text Every confirmed change in text of step triggers analysis of this step Step is enqueued and waits for analysis Restarting parser empties this queue Step that was 26 User Interface manually changed and is newly analysed comes to state calle

Procasor Project - Student`s research project server

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