YAWL Editor 1.1 User Manual
Contents
1. 1 Right click on the task and choose Update Flow Detail The number of splits will be the number of Target Tasks The currently selected flow in the dialog will also be identified by being drawn green in the Net Fig 30 Begin My Career set A Job Career Started Flow detail for Atomic Task Begin My Career Target Task Predicate Attend University _ true study Privately Cruel ELS Predicate The bottom most flaw will be used as the default Done Fig 30 Updating the Flow Detail 2 To choose the flow ordering select the Target Task that you want as the change the order of use the Up and Down arrows on the right to position the flow The bottom most flow will be used as the default if some flow needs to be followed but no predicates evaluate to true 3 To specify a predicate for a particular flow select the flow from the list and click on Predicate Enter a predicate as a boolean XQuery expression and choose Done YAWL Editor Manual Release 1 YAWL Editor Man vl doc 57 End of Scenario E This 1s where our scenario ends The My Career Scenario was designed to explain all the functions of the YAWL Editor and to provide you with a rudimentary understanding of designing a YAWL workflow specification But the complexity of the YAWL Editor does not stop with the current scenario If you are after something more challenging try adjusting your version of the scenario to expand into more2. 3 Click on the Remove Selected Items from Visible Cancellation Set button E on the Menu Toolbar Updating Data Type Definitions Version 1 1 of the YAWL Editor introduces the ability for workflow designers to specify data that is processed by a workflow XMLSchema is used to describe the valid data types that are available By default a number of simple XMLSchema data types are supplied for variable definition but if you need more complex data types you can supply your own XMLSchema definition to describe them 1 Select Update Data Type Definitions from the Specification Menu 2 Enter your XMLSchema Data Type Definition into the dialog box Fig 28 3 Ifthe definition text is green your new data type 1s now available for defining Net or Task variables in your specification If the text 1s red there is something wrong with your data type definition and the data type will not be available Update Data Type Definitions schema xmlns http www w3 ordmgq z l xMLSchema zcomplexType name Geek gt Sequence gt Selement name Mame type string gt element name 5alary type double Sequence gt lt complexType gt z schema pens cancer Fig 18 Adding the Geek complex data type YAWL Editor Manual Release 1 YAWL Editor Man v1 doc 26 E Open the Data Type Definitions dialog and type in the XML text that appears in Fig 18 The above example creates a complex data ty
3. specification Net Edit Tools Engine View Help meme n Me ale ENIE pu cu un ME Show hist Select a number of items to edit Fig 36 A simple specification showing how multiple instance tasks are done Fig 37 shows the core multiple instance queries used to manipulate a XMLSchema element defined for this specification The element has a complex type of BobList which defines a sequence of lt bob gt someText lt bob gt elements YAWL Editor Manual Release 1 YAWL Editor Man vl doc 42 Multiple Atomic Task verify list Instance Detail List Maker Masterlist for e in MasterList return xaomeBob i e text l SomeBob bob Verity list SomeBob texti l c bob EGE DH in Werify listrbob return 5H Fig 38 Example multiple instance queries YAWL Editor Manual Release 1 YAWL Editor Man vl doc 43 Time Service Example The example save file below supplied with the editor source gives you an example of how to build a task that calls through to the optional timer service supplied with the engine Fig 39 Fig 40 shows a user selecting the time service currently registered with a running YAWL engine as they generate their specification YAWLEdibor D YAWLEditorlibexampleEditorFiles simpleTimeServiceE amp ample 1 1 ywl Miel ES Specification Met Edit Tools Engine View Help Time limit setter Time limited task expiry Select a number o
4. By putting a join on a task you are telling the task that it could become available through the completion of one or more preceding tasks Below are some possible joins for a task e No join no join on task e AND join e OR join e XOR join For more information on join and split types please consult the YAWL technical papers on the YAWL website YAWL Editor Manual Release 1 YAWL Editor Man v1 doc 12 Creating Splits and Joins To create a split or join 1 Right click on your task and choose Decorate You will be presented with the Decorate window for your task which is divided between Join Decorator and Split Decorator options see Fig 6 Decorate Atomic Task Begin My Career x Jain Decorator Split Decorator Ho Join Or Join C No Splt gt Or Split C And Join C Xor Join C And Split Xor Split C2 North i East C2 South Fig 6 Decorating a Task 2 Choose the required split or join and the orientation for the split or join to appear and then click Done EH Right click on your Begin My Career task and change the split to Xor Split Then set the orientation to East as per Fig 6 a Create a new Atomic task called Do Private Study This task will represent those students that choose not to go to University E Finally right click on your Get A Job task and decorate it with an Xor Join Then set the orientation to West 3 Split and Join decorators allow you to connect several
5. Multiple Instance Variable Create Accessor Query Splitter Query ul Instance Query Aggregate Query E Result Net Variable Create pone Essi Fig 32 Data Manipulation for Multiple Instance Tasks To successfully specify multiple instance data manipulation you first need to select which of the task s decomposition variables will be used as the Multiple Instance Variable This variable needs to contain or can derive a number of unique values that will be separated with the Splitter query to pass a unique value per each instance task If the Multiple Instance Variable needs manipulation overall before the unique values are split out of it use the Accessor Query to do SO On the completion of an instance the Instance Query can be used to transform the XML document returned to a form suitable for the Aggregate query to finally generate an overall result The overall result will be assigned to the Result Net Variable on completion of the multiple instance task YAWL Editor Manual Release 1 YAWL Editor Man vl doc 40 Validating and Exporting At any stage you can validate or export your specification to a YAWL Engine executable XML file To Validate your specification 1 Click on Validate this Specification button vl on the Menu Toolbar or click Specification on the Menu and choose Validate Specification 2 A Validation Specification window will appear with d
6. a Cancellation Set 1 First select the task that will initiate the Cancellation Set using the Enter Marquee Selection Mode button from the Palette Bar 2 Right click on the task then choose Viewing My Cancellation Set The task will be coloured grey to indicate that this task 1s the cancellable task Go to the My Career Net We are going to make the Attend University task a cancellable task to demonstrate in the workflow that if a person executes this task then they don t have time to perform the Do Private Study task therefore it should be removed as an option Right click on Attend University and choose Viewing My Cancellation Set as per Fig 16 J amp Cut Ctrl X B Copy Ctrl C iil Delete Delete Begin My Career 7 tarted E a B Decorate OOOO m Update Parameters C Study Unfold to net Task Decomposition Detail H Viewing my Cancellation Set Fig 16 Viewing a task s cancellation set YAWL Editor Manual Release 1 YAWL Editor Man vl doc 24 3 E 4 E 5 Next using the Enter Marquee Selection Mode button from the Palette Bar choose a task condition or implicit condition to add to the Cancellation set Hold down the shift key to select more than one object for cancellation Select the Study Privately task and the Flow Relation preceding it Click on the Add Selected Items to Visible Cancellation Set button the Menu Toolbar It
7. by clicking on the Net Menu and choosing Update Net Detail B We are going to call this new Net Study Privately 7 Return to your original Net and right click on your Multiple Composite Task and choose Unfold to Net You will then be given a drop down list with all the Nets Available choose the Net for this task to initiate and then click Done A Choose Study Privately 8 You can now complete your new Study Privately Net represented by your Composite Task E Create the following Atomic Tasks in order and then link them with Flow Relations as per Fig 11 e Read a Book e Feel Smarter E Don t forget to validate your specification My Career m Begin My Career post Career Started Do Subjects Pass All Subjects set Degree Read A Book Feel Smarter Fig 11 Privately Study Multiple Composite Task and its Net YAWL Editor Manual Release 1 YAWL Editor Man v1 doc 19 Conditions Conditions are ways to represent a state in between tasks for the workflow To create a Condition l El 2 El 3 El El 4 5 Click on the Add a Condition button 9 in the Palette Bar or right click in the whitespace of the Net and choose Condition Go to the Do Private Study Net We are going to place a loop Condition after the Read a Book Atomic Task to determine whether we gained any knowledge from the book We will add the new Condition next Place your Condition in your Net and set
8. connectors indicated by two parallel blue lines on the sides of the objects and hold the left mouse button down and draw a line from the flow connector on the Input Condition to the one on the Atomic Task The editor will indicate which connection points are valid by drawing a blue box around suitable connectors as your mouse passes over them Begin My Career Fig 4 An established Flow Relation That s it Your Atomic Task is set YAWL Editor Manual Release 1 YAWL Editor Man vl doc 11 EH 7 Repeat the process for the following Atomic Tasks in order e Go to University e Get A Job e Begin My Career E 8 Link the Begin My Career task to the Output Condition the symbol as per Fig 5 E 9 Finally check the validity of specification by clicking on the Validate this Specification button v in the Menu Toolbar or click on Specification in the Menu and choose Validate Specification If all things are going to plan then you should receive a confirmation saying that there were no errors detected Begin My Career 5a To University et A Job Fig 5 The My Career Net Decorating a Task Decorating a task is the process of adding splits or join conditions on task By putting a split on a task you are telling the task that when it has been completed it s succeeding task could be one or more tasks Here are the possible splits for a task e No split no split on task e AND split e OR split e XOR split
9. of any task using this decomposition data could be transmitted via a Web Service to this company To a decomposition at a Web Service do the following 1 Right click on the task and choose Task Decomposition Detail An Update Task Decomposition dialog box will appear see the Web Services Detail box of Fig 24 2 Enter the following details regarding the Web Service e WSDL URL the location of the Web Service WSDL specification e WSDL Operation the operating command for the Web Service e YAWL Service the Service registered with the YAWL Engine 3 Click Done to finish If a valid running YAWL Engine instance can be connected to via the detail supplied in the section above the YAWL Service Dropdown Box will contain entries for all the Web Services that Engine can interact with Otherwise only the default manual Worklist YAWL service will be available Setting Multiple Instance Queries Multiple Instance Tasks need extra detail for data manipulation The Queries tab available by right clicking on a multiple instance task and selecting Set Instance Detail The Queries tab allows you to manipulate multiple instance data for the task YAWL Editor Manual Release 1 YAWL Editor Man vl doc 39 Right click on the task and choose Ensure that you are viewing the Queries tab of the dialog as per Fig 32 Multiple Atomic Task Do Private Study Instance Detail Bounds Queries
10. respective Done buttons clicking on the Done button when these fields still have focus will have the first button press event ignored Cutting and pasting net elements involved in a currently viewed cancellation set will have the newly pasted elements rendered as if they were still in a cancellation set Currently renaming a variable net or task decomposition does not also change XQuery XPath expressions that reference it Troubleshooting The YAWL Editor is not responding to my mouse clicks and it is beeping every time I click the mouse Check to see if you have any YAWL Editor dialog windows open These windows don t appear in the Windows Taskbar To check if you have any open dialog windows hold down the ALT key and press the TAB key With the ALT key held down press TAB until you reach the dialog window and let go of the ALT key Close the dialog window and you should be able use the YAWL Editor again Dialog windows appear as the Java icon blue coffee cup I can t connect two elements with a flow Why YAWL Editor Manual Release 1 YAWL Editor Man vl doc 45 If the editor does not allow you to connect one element to another it 1s steering you away from building an invalid net Typical examples include e Trying to connect a second flow to an undecorated task e Trying to point an incoming flow to a split decorator or an outgoing flow from a join decorator Se the troubleshooting entry How do I find o
11. s values changing The Update Parameters dialog box should appear as in Fig 29 YAWL Editor Manual Release 1 YAWL Editor Man vl doc 35 i Update Parameters for Atomic Task Enroll Input Parameters Task Variable Attend University Subjectlode textl sub jectCode Attend University Studenthumber text StudentNumber Create date n 1 E s Output Parameters Met Variable fEnroll SubjectCode textl sub jectCode fEnroll Studenthumber texti StudentMumber Fig 29 Established task parameters A brief introduction to XQuery e XQuery is a separate language that describes how to manipulate a given XML document to extract data from it For example the XQuery data my TaskVariable number 5 is saying that there is some XMLSchema element in an engine XML document with an element called myTaskVariable whose content is a number and that the resultant XQuery expression 1s that element s value with 5 added to it YAWL Editor Manual Release 1 YAWL Editor Man vl doc 36 Updating Flow Detail When dealing with tasks that have XOR and OR splits we need some way of telling a running engine which flows should be activated By updating the flow detail you can specify the default flow path and also establish predicates for each flow direction Flows whose predicates evaluate to true in a running engine will execute those flows To update the flow detail of a task that has a split
12. the keyboard We will add in the new composite task next Place your Composite Task in your Net Reconnect the Flow Relations from Begin My Career to the new Composite Task and from new Composite Task to Get a Job Create a new Net by clicking on the Create a new Net button El on the Menu Toolbar or click on Net in the Menu and choose Create Net Choose a name for this Net by clicking on the Net Menu and choosing Update Net Detail We are going to call this new Net Attend University YAWL Editor Manual Release 1 YAWL Editor Man vl doc 14 5 Return to your original Net and right click on your Composite Task and choose Unfold to net You will then be given a drop down list with all the Nets available choose the Net this task 1s to represent and then click Done Choose Attend University 6 You can now fill out the detail of your new Attend University Net Create the following Atomic Tasks in order and then link them with Flow Relations as per and don t forget to check for validity e Enrol e Do Subjects e Pass All Subjects e Get Degree My Career gt O D Begin My Career Get A Job Career Started Attend Universi Lo Private Study Attend University Enroll Do Subjects Pass All Subjects set Degree Fig 8 Attend University Composite Task and its matching Net Multiple Atomic Tasks Multiple Atomic Tasks are allow you to run multiple instances of a
13. the task needs processing S Set the Minimum Instances to 5 5 Set the Maximum Instances value This is the maximum number of instances of this task that can be created El Set the Maximum Instances to 100 6 Setthe Continuation Threshold value The moment all instances created have completed or as many instances as the Continuation Threshold specified have completed the multiple instance task itself 1s considered completed which triggers relevant outgoing flow relations from this task El Set the Continuation Threshold to 50 YAWL Editor Manual Release 1 YAWL Editor Man vl doc 16 Multiple Atomic Task Do Private Study Instance Detail Bounds Queries Minimum Instances Maximum Instances gt is infinite wis equalto 100 Continuation Threshold CO is infinite is equalto so Instance Creation Static 2 Dynamic rcm Fig 10 Instance Bounds on Multiple Instance Tasks 7 Choose the Instance Creation If a multi instance task has static creation mode when the task 1s started the number of instances created 1s decided then and cannot be altered during the execution of the task Conversely if a task has dynamic creation mode then new instances of the task can start once the initial minimum instance number of tasks has started but before the maximum number has been received E Set the Instance Creation type to Static 8 Click Done With the values set in the scenario
14. Flow Relations from and to your task respectively a Create a flow relation from Begin My Career to Do Private Study then create another flow relation from Do Private Study to Get A Job as per Fig 7 S 4 Don t forget to check the validity of your specification Hint If you are having troubles with positioning your tasks the alignment tools are a big help YAWL Editor Manual Release 1 YAWL Editor Man vl doc 13 Begin My Career Get A Jab Career Started Ja Private Study Fig 7 XOR Split and Join When Begin My Career has been completed a choice must be made on which of the two tasks Go To University or Do Private Study will be followed XOR Split Composite Tasks Get a Job will become available after the completion of the task selected at the point of the XOR split Composite tasks are place holders for other YAWL Nets That is you can create another workflow in a separate Net which 1s represented by the composite task in other nets To create a Composite Task l E 2 E 3 4 Click on the Composite Task button B in the Palette Bar or right click in the whitespace of the Net and choose Composite Task We are going to replace our existing Go to University Atomic Task with a composite task so choose the Enter Marquee Selection Mode button on the Palette Bar click on the Go to University Atomic Task and press the Delete key on
15. Select this button to create a Composite Task which is a container for another YAWL Net with its own set of Y AWL elements constrained by the same syntax Multiple Atomic Task cu Select this button to create a Multiple Atomic Task which allows you to run multiple instances of a task concurrently Multiple Composite Tasks a Select this button to create a Multiple Composite Task which allows you to run multiple instances of a composite task concurrently Flow Relation E Select this button to create a Flow from one task to another YAWL Editor Manual Release 1 YAWL Editor Man v1 doc T Condition 9 Select this button to create a Condition which is a way to represent state for the Net Marquee Selection Select this button to activate the Marquee Selector which will allow you to select individual or multiple objects by clicking and dragging your left mouse button Status Bar The Status Bar provides useful hints throughout the creation of your specification and depending upon which object you are using in the Palette Bar Canvas The Canvas is where you will be creating and editing your workflow diagram s Menus Overview This section provides a brief overview of the YAWL Menus located along the top of the YAWL Editor specification Net Edit Tools Engine View Help Specification The Specification Menu provides all the standard file options of Create Open save Close and Exit It also co
16. YAWL Editor 1 1 User Manual Release 1 0 QUT Faculty of Information Technology YAWL Editor User Manual Release 1 YAWL Editor User Man vl doc Document Control 26 Oct 2004 sean Kneipp 0 4 Updated Engine Integration YAWL Editor Manual Release 1 YAWL Editor Man vl doc ll Contents Docurnent CODE ONY e ecieedlipl baute tacet ott boite ttti denos e deueliol idunt auton ll NV CLC OMG T0 pratt tray siste atat teta on eee eee l Wiat 1S YAWE s sis eod eti o di a rette adm AE oet uiu N se deridet l Obtaining the Latest Version of the YAWL Editor sssess l Lhe X A WEPIOEC uione E E A 2 b t Ee APC IEC Dui e I 2 Cre BEIHIO SEDE Cetin tase ate iuo Sects elated usan Seance ect Mu dade t eti CU 3 CODVEPDEDDNNOHCS niece petu que Mn usas tudin deoa ics e tust stie eia iu ed 3 Launchtae the Y AW E BEOIOE onem hod ti es etd p eite to tates eb t e etas 3 The X AW ls Editor Workspace 2 oed tomes cube oue totus A 4 INICIO UL eye Lor cocotte ee arene nme ety eee eae he eee me a Lene LU EIE 4 lige atom b i greene Serer ree etme Aen eee ne ee tae ata ae eee ee ee eee ne eee 7 SPAS SAN coset deutet didam eg iuter aes Case nase bhi detent ced EDDIE 8 CII e 8 Men s OVS IVIC Wor n t 8 Creatine Your First SDOeLHCOLOLD sining oae edu eto eed tbe uae ted edu de 10 OVELVIC Wy ia i hh sin are i tte cect en etus Salone Goeth cane enn Ste
17. anguages supported by contemporary workflow management systems While not a commercial language itself it encompasses these languages and in addition has a formal semantics Such an approach is in contrast with e g WfMC s XPDL which takes commonalities between various languages as a starting point and does not have formal semantics Its design hopefully allows YAWL to be used for the purposes of the study of expressiveness and interoperability 1ssues At this stage YAWL supports the control flow perspective and the data perspective However it is important that relations with the resource perspective are investigated and formalized For YAWL to be more applicable in the area of web services and Enterprise Application Integration it is also desirable that support for communication patterns 1s built in Obtaining the Latest Version of the YAWL Editor As new versions of the YAWL Editor are released to the public they will be available for download at the YAWL website http www citi qut edu au yawl Developers interested in obtaining the YAWL Engine can download the files from the YAWL website above The source code for all ofthe YAWL components can be downloaded through the SourceForge Website http sourceforge net projects yawl a YAWL Editor Manual Release 1 YAWL Editor Man vl doc l The YAWL Project For more information and progress on the YAWL project visit the YAWL Homepage on Queensland University of Technology s Cent
18. arate ata 10 PES CCN AMO ret incest ta a malto dest diubeno 10 Creating Your First Specification ssssssssssssseeeeeeeeee nennen 10 AOMC aS Sonn Po DN aD MEUM EIE DE 11 Decorate a Pask uu atio xb estie cob oa tiet ebat cuia dua t DAS 12 Composite TASKS osos estimer nma A EA ins Ae Ete uinum 14 Multiple Atomic EaskS uude dates tae a teo oe D bo abd t 15 Multiple Composite Tasks pasepan heme abiti et Inani chiese ln Ipse L STG NS se E E ota Le tenes I IE 20 Changi the Staring NCU S doe oc eU A a eed oie 21 Changing the Appearance of Your Specification eese 22 Improving the Look of Flow Relations eeeeeeeeeenen 22 Editing ODISE Sei eus iioi tese ep med tessera ufa d abd 23 Changing Font SIZ6 5 odneodeecto trend neg de a oett an dota edet oa dean pacis uat dota 23 Advanced Specification Beatus soe ette eno E EDI eee 24 Bue EINER ENTE EU T LC UOTE 24 Updating Data Type Definitions eeeeessssssssseeeeeeeennn aE 26 Net Decomposition Detail Updating Net Variables 2 Task Decomposition Detail Updating Task Variables 30 Adding Updating Task Parameters see 32 Updating Plow Detatl e E E na e E E ERE tni nati a 37 FTG IOS COMA IO eeror a a E E Sein A 38 oer X AI Bere detalla tede trt er dota tremit Word essei dtl edi uie 38 setting Multiple Instance QUGTFIOS eerta I hr nv ue da Esth t
19. art the application and away you go YAWL Editor Manual Release 1 YAWL Editor Man vl doc 3 The YAWL Editor Workspace The first time you start the YAWL Editor you will be presented with a blank canvas with the instructions in the Status Bar asking you to open or create specification to begin Before you create your first specification let us take a brief tour of the Editor s workspace and the elements within YAWLEditor Spect ication Met Edit Tools Engine View Help Geese Via ele Diels FEE a OE Tear away Menu Toolbar The Canvas Tear away Palette Bar Status Bar supplying hints and messages on what can be done open or create a specification to begin Fig 2 The YAWLEditor Workspace Menu Toolbar The Menu Toolbar contains six groups of buttons to assist you in maintaining your YAWL specification The menu can be repositioned by dragging the left hand anchor bar Specification Maintenance IPTE YAWL Editor Manual Release 1 YAWL Editor Man vl doc This group of buttons provides you the standard options to create save open and close YAWL specification files YAWL Editor Manual Release 1 YAWL Editor Man vl doc Specification Verification amp Exporting vial These two buttons allow you to validate your specification for any workflow inconsistencies and then export your workflow diagram into an XML file for uploading to the YAWL Engine Net Mai
20. arting Net At any stage you can change the starting Net of the specification To change the starting Net 1 Select Net from the Menu 2 Choose Set Starting Net 3 From the Choose Starting Net window click on the drop down list and select a new starting Net 4 Click Done Execution af the workflow starts in net MyCareer Attend University Fig 13 Changing the Starting Net YAWL Editor Manual Release 1 YAWL Editor Man vl doc 21 Changing the Appearance of Your Specification Improving the Look of Flow Relations You can control and improve the look of the Flow Relations by adding in knees 1 Select the Enter Marquee Selection Mode button from the Palette Bar El Go to the Do Private Study Net 2 Right click on the position in the Flow Relation where you want to add a knee signified by a small square in the Flow Relation E Right click somewhere on the Flow Relation going from Knowledge Gained Condition to Look for an Easier Book Atomic Task 3 Then left click on the knee and drag it out to a more desirable location You can add as many knees to a Flow Relation as you like E Repeat the process for the Flow Relation between Look For an Easier Book and Read A Book tasks see Fig 14 M 9 Read A Book Knowledge tained Feel Smarter Fig 14 Adding knees to a Flow Relation YAWL Editor Manual Release 1 YAWL Editor Man vl doc 22 Editin
21. as Lindsay Bradford L achlan Aldred YAWL Editor Manual Release 1 YAWL Editor Man vl doc 47
22. being ordered Adding a Variable to a Task 1 First select the task that will require the variable using the Enter Marquee Selection Mode button 3 from the Palette Bar A We will be setting up variables for the Enroll task E Go to the Attend University Net and select the Enroll task 2 Right click on the task and choose Task Decomposition Detail An Update Task Decomposition dialog box will appear Fig 24 E Retrieve the decomposition detail for the Enroll task YAWL Editor Manual Release 1 YAWL Editor Man vl doc 30 Update Task Decomposition Enroll Decomposition Label Enroll Decomposition Variables Ma Type sage Create Web Service Detail TAWL Service WSDL Operation WSDL URI pone cancer Fig 24 Updating variables for a task 3 Click on the Create button An Update Task Variable dialog box will appear 4 Enter the Name of your variable choose the Type of the variable from the list optionally enter an Initial Value for the variable then click Done then Done again to exit the task decomposition detail dialog Type in StudentNumber for the name of the variable and choose the type string Leave the Initial Value blank Fig 25 YAWL Editor Manual Release 1 YAWL Editor Man vl doc 31 i Update Net Decomposition Decomposition Label Enroll Decomposition Variables Ma Type sage Create Web Se
23. ecomposition Label field then click the Done button Decomposition Variables will be explained later in the Net Decomposition Detail section of this manual YAWL Editor Manual Release 1 YAWL Editor Man vl doc 10 E Change the name of the Net in the Decomposition Label to My Career This Net will be the primary net for our scenario 4 Youare now ready to start drawing your specification Atomic Tasks 1 Click on the Add an Atomic Task button O in the Palette Bar or right click in the whitespace of the Net and choose Atomic Task 2 Position your mouse just to the right of the Input Condition the symbol and click the left mouse button once to place an Atomic Task 3 Set the decomposition of this task by right clicking on the Atomic Task and choosing Select Task Decomposition e tf H N N Set decomposition ta Create tone Emi Fig 3 The Update Task Decomposition dialog 4 Press the Create button and in the following window Update Task Decomposition enter the decomposition s label See the Select Task Decomposition section of this manual for a full explanation of its features A Set the label to Begin My Career and click the Done button 5 Select the Flow Relation button gt l in the Palette Bar or right click in the whitespace of the Net and choose Flow Relation 6 Connect the Input Condition to your Atomic Task by finding the flow
24. ems will be coloured red to indicate belonging to the cancellation set see Fig 17 Add the Study Privately task and the preceding Flow Relation to the cancellation set Once you have established the cancellation set you can right click on the cancellable task and tick off Viewing My Cancellation Set option Attend University Begin My EE Career Started Study Pr ivatel Fig 17 Adding elements to a Cancellation Set Notes about Cancellation Sets A Cancellation Set that has been created will remain in the workflow regardless of whether you have the Viewing My Cancellation Set option ticked You can create multiple Cancellation Sets in your workflow by selecting another task and choosing the Viewing My Cancellation Set option All flows leading to or from conditions are not valid cancellation set members Neither are the Input and Output conditions The editor will ignore them if you select them for inclusion in a task s cancellation set YAWL Editor Manual Release 1 YAWL Editor Man vl doc 22 To remove an element from a Cancellation Set 1 First make sure you have the Viewing My Cancellation Set option ticked If it isn t ticked select the task that is initiating the Cancellation Set using the Enter Marquee Selection Mode tool from the Palette Bar and right click then choose Viewing My Cancellation Set 2 Select the element for removal using the Enter Marquee Selection Mode button
25. etails of any inconsistencies in the specification or you will get a window confirming that your specification is valid Fig 33 shows an example valid specification Fig 34 shows an example invalid specification test Specification is valid X Ho problems were detected with this specificatian Fig 33 A Valid Specification New Net 1 broken test 2 Yalidate Specification Problem Atomic Task 3 The outgoing Clow number must be gt O Atomic Task 3 is not on a backward directed path between the input and output conditions Done Fig 34 An Invalid Specification YAWL Editor Manual Release 1 YAWL Editor Man vl doc 4 To Export your specification to an XML file 1 Click on Export this specification to the YAWL Engine file format button Fy on the Menu Toolbar or click Specification on the Menu and choose Export to YAWL Engine File 2 A window will appear asking you wear to save the file 3 Select a location and choose Save This specification save file can now be loaded into a running YAWL Engine and executed Illustrative Examples Multiple Instance Task Example The example save file below supplied with the editor source gives you an example of how to process a simple multiple instance task with its queries filled in Fig 35 2 TAWLEditor D TAWLEditor lib exampleEditaorFiles simpleMultipleInstanceE amp ample 1 1 y wl IE XI AFERE e a um
26. f items to edit Fig 41 Example showing the usage of a custom YAWL service 5 Update Task Decomposition Time limited task expi EA Decomposition Label Time limited task ex Decomposition Variables Web Service Detail TAWL Service Default Engine VVorklist E WSDL Operation Default Engine Worklist RPC Style Web Semice Invaker WSDL URI C Done cancer Fig 42 Assigning a registered YAWL service from a running engine YAWL Editor Manual Release 1 YAWL Editor Man v1 doc 44 Known Issues We need to find a way of getting the clipboard to notify listeners of updates Currently we kludge up whether the Paste action can be activated by simply turning it on when an editor user uses Cut or Copy in the same editor Editor elements cannot currently be cut paste across two running editors on the same machine The creation and deletion of nets need to be undoable edits Until the deletion of nets becomes an undoable edit deleting a net will cause odd undo behaviour with respect to composite tasks that used to reference the deleted net Having spaces in the file path of the editor will cause the XMLSchema validation to stop working Validation uses temporary files that are getting confused by the spaces The menu item Print Specification freezes 1f not used for some time For variable name fields and decomposition label fields that drive the enabled state of their
27. g Objects You can edit more than one object at a time by using the Enter Marquee Selection Mode tool See Fig 15 1 Select the Enter Marquee Selection Mode button from the Palette Bar 2 Click on the first object that you want to edit 3 Hold down the shift key and then click on the other objects that you want to edit 4 Now choose the Edit option from the Menu or continue holding down the shift key and right click on the mouse button Below are the edit options e Cut Copy Delete e Align e Size Increase Decrease to change the appearance of the objects This can also be done using the CTRL key plus Up or Down arrow on your keyboard Read A Book Knowledge Gained Feel Smarter d gl gl Fig 15 Changing the Size of Multiple Objects Changing Font Size You can change the size of the font used to label tasks and conditions 1 Change the font size by clicking on the View Menu and choosing the Label Font Size option E Change the font size to 18 YAWL Editor Manual Release 1 YAWL Editor Man vl doc 23 Advanced Specification Features Cancellation Sets Cancellation Sets allow you to nominate any number of tasks conditions or implicit conditions which exist on flow relations between tasks but are not drawn for cancellation upon the execution of a specified task That is once a specified task 1s executed in the workflow all state within that task s cancellation set is removed To create
28. ies the net variable currently selected in the net variable drop down box El Select the SubjectCode variable from the list of Existing Task Variables Select the SubjectCode net variable and click XQuery Alter the query to extract the net variable s content by adding text to the end of the m query Fig 28 Click Done Create another Task Parameter and map the net StudentNumber to the task variable of the same name using this technique Click Done and Done again i Update Task Parameter SubjectCode net variable SubjectCode od XQuery fAttend University subjectlode text XQuery populates task variable SubjectCode Create Done Cancel Fig 28 Passing a net s SubjectCode to a Task To add an Output Parameter 1 First select the task that will require the parameter using Enter Marquee Selection Mode button E from the Palette Bar A We will be setting up Output Parameters for the variables that we created in the Adding Updating TaskVariables section YAWL Editor Manual Release 1 YAWL Editor Man v1 doc 34 Go to the Attend University Net and select the Enroll task 2 Right click on the task and choose Update Parameters An Update Parameters dialog box will appear Fig 27 E Update the Parameters for the Enroll task 3 In the Output Parameters section click on Create An Update Net Parameter dialog box will appear s
29. imilar to Fig 28 5 Ifyou have already set up a Task Variable for this task then the Existing Task Variable option will be activated and there will be a list of task variables to choose from Choose a variable from the list and click on Done then Done again to close the task parameters dialog If you haven t set up Net Variables then click on Create and return to the previous section in the manual for Adding a Net Variable If you are familiar with XQuery syntax then you can paste in an XQuery to allow manipulation of the Input Parameters Syntactically well formed XQueries will be green and badly formed ones will be red As a convenience method the XQuery button will generate an engine compatible XQuery that supplies the task variable currently selected in the task variable drop down box 4 Select the SubjectCode variable from the list of Existing Net Variables Select the SubjectCode task variable and click XQuery Alter the query to extract the task variable s content by adding text to the end of the query Click Done Create another Task Parameter and map the task StudentNumber to the net variable of the same name using this technique Click Done and Done again These Output Parameters were set up to demonstrate a simple transfer of state from a net to a task and back to the net Perhaps the task would allow a user to change the values of one of the variables which would eventuate in the net
30. lationship between task decompositions scoped to the entire specification and their tasks scoped to nets Besides variables and a label task decompositions also allow the workflow designer to identify which web service the decomposition should invoke in a running workflow engine When two tasks share the same decomposition we are saying that the same activity 1s required in two different places in the workflow You can use the drop down list to select the task decomposition of a task or alternately you can press the Create button and generate a new one that will automatically become the task s decomposition Fig 23 YAWL Editor Manual Release 1 YAWL Editor Man vl doc 29 Career Started Atomic Task Get A Job Eq Set decomposition to Getas v Get A Job dE Create Buy Look for an Easier Book Read A Book Fig 23 Select Task Decomposition Task Decomposition Detail Updating Task Variables You can add variables to a task to store specific information relating to that task Task variables have several uses One use is to transferring information between workflow users and the workflow engine A second use is for passing data between web services that the running workflow engine invokes and the Net the task resides in For example if your task 1s called Place an Order you may want to store the name or identification number of the person placing the order or maybe store the items
31. mice Detail TAWL Service WSDL Operation WSDL URI pone coa Fig 25 Updating the Task Variable E 5 Create another variable for the same task called SubjectCode with the type being string and usage being Input amp Output Click Done Fig E 26 The Enroll task now has two variables StudentNumber and SubjectCode Update Task ariable Name StudentNumber Type string Usage Input amp Output C Done cancer Fig 26 Updating another Task Variable Adding Updating Task Parameters Both Input and Output Parameters can be assigned to any tasks to allow the passing of state between nets and their tasks and between tasks and workflow engine users and web services YAWL Editor Manual Release 1 YAWL Editor Man v1 doc 22 Input Parameters use an XQuery to massage net variable state across possible several net variables into a value that can be passed to a single selected task variable Output parameters use an XQuery to massage task variable state across possible several task variables into a value that can be passed to a single selected net variable For example if a task 1s called Place an Order then an Input Parameter could be the name of the person placing the order whereas the Output Parameter could be the corresponding identification number of that person To add an Input Parameter 1 First select the task that will require the paramete
32. ntains options to validate and export the specification to the YAWL Engine XML format as well as updating the specification s data type definition in XMLSchema format and for printing the specification Net The Net Menu provides options to Create Remove set the Starting Net and specify decomposition detail for the currently selected net It also provides options to export a net to a PNG image file and for directly printing out the net YAWL Editor Manual Release 1 YAWL Editor Man vl doc 8 Edit The Edit Menu provides the standard options of Undo Redo Cut Copy Paste and Delete objects within your specification Tools The Tools Menu allows you to align objects within your specification modify their size or add or remove objects from your Cancellation Set Engine The Engine Menu allows you to specify a running engine that the editor should connect to so you can tailor your workflow designs to specific modules and web services installed in the engine View You can use this menu to turn off or on the Tooltips which provide useful hints when your mouse is positioned over a toolbar button or an option in a pop up dialog window obtained by right clicking on the canvas It also allows you to change the font size used for element labels Help The Help Menu provides details of the YAWL Editor copyright as well as Acknowledgements for all the dedicated YAWL contributors YAWL Editor Manual Release 1 YAWL Edito
33. ntenance EE Your workflow diagrams are captured within Nets of which a specification could contain many You can use these buttons to create a new Net or remove existing Nets within your specification Edit Options ejem These group of buttons provides the standard Undo and Redo options as well as the option to delete the currently selected objects Alignment Options uu Se ie These buttons can be used to assist with the alignment of objects within your specification when multiple objects have been selected Object Sizes EXET To increase the size of an object within your specification select the object s and then use these buttons Cancellation Sets These buttons allow you to include in and or exclude elements from the cancellation set of a task YAWL Editor Manual Release 1 YAWL Editor Man vl doc 6 Palette Bar The Palette Bar contains seven selector buttons that assist with creation selection and positioning of objects within your specification This menu can be repositioned by dragging the left hand anchor bar The Palette bar is also accessible by right clicking anywhere on a net that does not contain a net element Once an element is selected it is possible to drop objects in the canvas by left clicking the mouse button Atomic Task ol Select this button to create an Atomic Task which represent a single task to be performed by a human or external application Composite Task o
34. of the Multiple Composite Task Right click on the task and choose Set Instance Detail 9 Set the Minimum Instances value This is the minimum number of instances of this task that will be started when the task needs processing S Set the Minimum Instances to 5 10 Set the Maximum Instances value This is the maximum number of instances of this task that can be created El Set the Maximum Instances to 100 11 Set the Continuation Threshold value The moment all instances created have completed or as many instances as the Continuation Threshold specified have completed the multiple instance task itself 1s considered completed which triggers relevant outgoing flow relations from this task E Set the Continuation Threshold to 50 12 Choose the Instance Creation If a multi instance task has static creation mode when the task 1s started the number of instances created 1s decided then and cannot be altered during the execution of the task Conversely if a task has dynamic creation mode then new instances of the task can start once the initial minimum instance number of tasks has started but before the maximum number has been received E Set the Instance Creation type to Static 4 Click Done 5 Create a new Net by clicking on the Create a new Net button Bl on the Menu Toolbar or click on Net in the Menu and choose Create Net YAWL Editor Manual Release 1 YAWL Editor Man vl doc 18 6 Give the new Net a name
35. pe called Geek that has two separate sub components Name and Salary of type string and double respectively As depicted in Fig 19 the new data type Geek is available to choose when creating a task or net variable Update Net Variable testGeek Name testGeek Type Geek Usage Input amp Output Y Initial Value ssrccesi zxName Lindsay c Mame zSalaryee n n n0e Salary z testbeek pone coca Fig 19 A Geek task variable Net Decomposition Detail Updating Net Variables You can add variables to a net to store information relating to that net that tasks within the net may need to read or update To add a variable to a Net 1 Choose Update Net Detail from the Net Menu E We will be setting up Net variables in the Attend University net E Go to the Attend University Net and choose Update Net Detail from the Net Menu 2 An Update Variables dialog box will appear Fig 20 3 Click on Create An Update Net Variable dialog box will appear YAWL Editor Manual Release 1 YAWL Editor Man vl doc zu Update Net Decomposition Attend University E3 Decomposition Label Attend University Decomposition Variables Ma Type sage Create pone cancer Fig 20 Updating Attend University Net Variables 4 Enter the Name of your variable choose the Type of the variable from the list optionally enter an Ini
36. r using the Enter Marquee Selection Mode button from the Palette Bar A We will be setting up Input Parameters for the variables that we created in the Adding Updating Task Variables section previously E Go to the Attend University Net and select the Enrol task 2 Right click on the task and choose Update Parameters An Update Parameters dialog box will appear Fig 27 E Update the Parameters for the Enrol task Task Variable i Create Output Parameters Met variable Fig 27 Updating Parameters for a Task 3 In the Input Parameters section click on Create An Update Task Parameter dialog box will appear YAWL Editor Manual Release 1 YAWL Editor Man vl doc 33 4 If you have already set up a Task Variable for this task then the Existing Task Variable option will be activated and there will be a list of task variables to choose from Choose a variable from the list and click on Done then Done again to close the task parameters dialog If you haven t set up Task Variables then click on Create and return to the previous section in the manual for Adding a Task Variable If you are familiar with XQuery syntax then you can paste in an XQuery to allow manipulation of the Input Parameters Syntactically well formed XQueries will be green and badly formed ones will be red As a convenience method the XQuery button will generate an engine compatible XQuery that suppl
37. r Man vl doc Creating Your First Specification Overview The Scenario This next chapter will lead you through the process of creating a YAWL specification from beginning to end through a series of brief lessons following a scenario You can either follow the all the instructions including the scenario provided from beginning to end or skip straight to the section that you are interested in and follow the instructions Look for the blue S next to the instructions for specific details of the scenario The scenario that we will be following throughout this manual is the workflow of a student who has just completed their secondary study and is now looking to start their career This scenario will follow the path of a student who either enrols in a University to complete their tertiary eduction or undertakes private study which will eventually lead them to getting a job and starting their new career Creating Your First Specification 1 Click on the Create a New Specification button E at the top left of the Menu Toolbar or click on Specification in the Menu and choose Create Specification This will bring up a blank Net called New Net 1 which will be by default the starting net of the workflow For details on selecting a starting net consult the Changing the Starting Net section in this manual 2 Rename this Net by clicking on the Net Menu and choosing Update Net Detail 3 Enter the new name of the Net in the D
38. re for Information Technology Innovation website http www citi qut edu au yawlz YAWL Architecture The following image Fig 1 depicts the interaction between components of the YAWL Engine Apache Tomcat worklist war yaw war Web Service yawlWSInvoker war NE Lie RR YAWL Editor Fig 1 The YAWL Components YAWL Editor Manual Release 1 YAWL Editor Man vl doc Getting Started Copyright Notice Copyright to this software and its source code 1s granted under the GNU Lesser General Public Licence v2 1 For detail on the permissions this licence grants you please refer to http www gnu org copyleft lesser html z This editor makes use of JGraph 3 1 This version of the JGraph library 1s covered under a BSD style licence and 1s available separately from http www jgraph com z This editor also makes use of code from the YAWL Engine and its support libraries The engine and its support libraries are covered under their own individual copyright licences detail of which may be found at the YAWL website http www citi qut edu au yawla In accordance with this editor s copyright licence the source code may be obtained from the YAWL SourceForge website http sourceforge net projects yawl a Launching the YAWL Editor 1 Download the latest version from the YAWL SourceForge website http sourceforge net projects yawl z 2 Double click on the YAWLEditor jar file to st
39. sub Nets and more complex situations Set YAWL Engine Detail By specifying the location of a running instance of the YAWL Engine it 1s possible to have the editor generate specifications that take advantages of that YAWL engine s specific setup For this release of the editor the engine behaviour available is limited to a number of web services that the engine has been configured to interact with Further detail on specifying web services to have the workflow interact with can be found in the next section To set the YAWL Engine details 1 Click Engine on the Menu and choose the Set Engine Detail item 2 From the resulting dialog Fig 31 accept the default values or enter the following engine details e YAWL Engine URI e User Name e Password e Verify Password The YAWL Engine URI value will default to a locally installed YAWL Engine administration URI The User Name and Passwords will default to the engine default admin user YAWL Editor Manual Release 1 YAWL Editor Man vl doc 38 TAWL Engine URI hitplocalhost 8080 yawliia User Name admin si Password m Verify Password m Fig 31 Specifying the YAWL Engine Details Connecting a Decomposition to a Web Service You can use task decompositions within your workflow to make a connection to a Web Service when activated through the YAWL Engine For example a decomposition may be set up to place an order with an external company Upon execution
40. task concurrently To create a Multiple Atomic Task 1 Click on the Add Multiple Atomic Task button a in the Palette Bar or right click in the whitespace of the Net and choose Multiple Atomic Task YAWL Editor Manual Release 1 YAWL Editor Man vl doc 15 E Go back to the My Career Net We are going to replace our existing Do Private Study Atomic Task with a Multiple Atomic task so choose the Enter Marquee Selection Mode button on the Palette Bar click on the Do Private Study Atomic Task and press the Delete key on the keyboard We will add in the new Multiple Atomic task next 2 Place your Multiple Atomic Task in your Net and set the name of this task by right clicking on the task and choosing Select Task Decomposition E Call this task the same name as before by selecting the Do Private Study decomposition from the drop down list Reconnect the Flow Relations from Begin My Career to Do Private Study and from Do Private Study to Get A Job as per Fig 9 Attend Universi set A Job Career Started Do Private Study Fig 9 Adding a Multiple Atomic Task 3 You will now need to set the parameters of the Multiple Atomic Task Right click on the task and choose Set Instance Detail Ensure that you are viewing the Bounds tab of the dialog as per Fig 10 4 Set the Minimum Instances value This is the minimum number of instances of this task that will be started when
41. the Do Private Study task is indicating that a maximum of 100 instances of this task can be executed before triggering the task s outgoing flow A minimum of five instances will be created and once 50 instances have completed the outgoing flow relations to Get A Job will trigger The Queries tab of the Multiple Instance dialog will be explained later in the Setting Multiple Instance Queries section of this manual Multiple Composite Tasks Multiple Composite Tasks allow you to run multiple instances of the Net represented by a multiple composite task concurrently YAWL Editor Manual Release 1 YAWL Editor Man vl doc 17 To create a Multiple Composite Task 1 Click on the Add Multiple Composite Task button E in the Palette Bar or right click in the whitespace of the Net and choose Multiple Composite Task E Go to the My Career Net We are going to replace our existing Do Private Study Multiple Instance Task with a Multiple Composite task so choose the Enter Marquee Selection Mode button on the Palette Bar click on the Do Private Study Task and press the Delete key on the keyboard We will add in the new Multiple Composite task next El 2 Place your Multiple Composite Task in your Net Reconnect the Flow Relations from Begin My Career to the new Multiple Composite Task and from the new Multiple Composite Task to Get a Job 3 You will now need to set the parameters
42. the name by right clicking on the Condition and choosing Set Label Call this Condition Knowledge Gained Now link to the Condition using the Flow Relations object Select the Enter Marquee Selection Mode button from the Palette Bar and click on the Flow Relation going from the Read a Book Atomic Task to the Feel Smarter Atomic Task and press the Delete button on the keyboard Create a Flow Relation from Read A Book to Knowledge Gained Create a Flow Relation from your Condition to a task Set the Flow Relation from Knowledge Gained Condition to Feel Smarter Atomic Task Create another Flow Relation from your Condition to another task to signify the two possible flows from the Condition Before we create our second flow relation from our Condition create another Atomic Task and call it Look for Another Book Change the Join Decoration for Atomic Task Read a Book to an OR Join with the orientation being West by right clicking on Read a Book and choosing Decorate Click Done Finally create the Flow Relation from the Knowledge Gained Condition back to the OR Join of the Read A Book Atomic Task as per Fig 12 YAWL Editor Manual Release 1 YAWL Editor Man vl doc 20 Study Privately Look foran Easier Bogt Knowledge Gained Feel Smarter Fig 12 Condition Loop for Do Private Study Net E Last but not least validate your specification Changing the St
43. tial Value for the variable then click Done then Done again to close the Net Decomposition dialog E Type in StudentNumber for the name of the variable and choose its type as string Leave the Initial Value blank and Usage as Input amp Output Fig 21 Click Done Create another Net Variable with the name SubjectCode and Type of string Leave the Initial Value blank and Usage as Input amp Output Click Done i Update Net Variable Name StudentNumber Type string Usage Input amp Output 7 Initial Value Po pone coca Fig 21 The Net Variable StudentNumber 5 The Net Variables should now appear in the Update variables of Net Attend University dialog box Fig 22 YAWL Editor Manual Release 1 YAWL Editor Man vl doc 28 2 Update Net Decomposition Attend University Decomposition Label attend University Decomposition Variables sub JectCode string Input Output Create atudentNMumber string Input s Output pone cancer Fig 22 Updated Attend University Net Variables Select Task Decomposition By choosing the Select Task Decomposition option when you right click on a task you have the ability to identify which decomposition this task represents Like nets tasks have decompositions where you can specify variables and a label to associate with the task or net Unlike nets which cannot share net decompositions there is a 1 N re
44. u A lu pides 39 MValidaumng and B XDOFIIBDB 5i eite tret Ete tapete heh ibendum ode 4 IHusttattvecBXxanpleS uoi ei ari ea oe RP ee detis E 42 Muluple Instance Task Exainiple criss secs eer tas riii etii tos d eden ced 42 TIe Service EXAMS erinan n doeet piat uicta UEM bI 44 SO i SSUCS t M ee 45 THOUDIE SHOOTING cL O A M 45 ACKWBOWIedP etie HIS ceno e ES SINCE DUNT NU La Ee IM e RES TAN M A EPI 47 YAWL Editor Manual Release 1 YAWL Editor Man vl doc il Welcome to YAWL What is YAWL Based on a rigorous analysis of existing workflow management systems and workflow languages we have developed a new workflow language YAWL Yet Another Workflow Language To identify the differences between the various languages we have collected a fairly complete set of workflow patterns Based on these patterns we have evaluated several workflow products and detected considerable differences in expressive power Languages based on Petri nets perform better when it comes to state based workflow patterns However some patterns e g involving multiple instances complex synchronizations or non local withdrawals are not easy to map onto high level Petri nets This inspired us to develop a new language by taking Petri nets as a starting point and adding mechanisms to allow for a more direct and intuitive support of the workflow patterns identified YAWL can be considered a very powerful workflow language built upon experiences with l
45. ut more about elements and principles for more detail When I validate my Net I get the following validation message The net may complete without any generated work Should all atomic tasks in the net be unlabelled This message appears if you have not labelled any of your tasks To label a task and thus ensure that the engine will get a user to handle the task at this point in the workflow right click on the task and choose Select Task Decomposition Choose Create and in the following window Update Task Decomposition and enter the name of your task under Decomposition Label then click Done To label a Condition right click on a task and choose Set Label then type in a name for the label and click Done My specification won t validate without any errors and I don t know what to do First check the logic of your specification and exercise every branch of your workflow for correctness If you are sure of your workflow consult the YAWL website for the proper use of the YAWL elements http www citi qut edu au yawl How do I find out more about the elements and principles of the YAWL workflow specifications For more information about the mechanics of the YAWL workflow elements please consult the YAWL website http www citi qut edu au yawl z YAWL Editor Manual Release 1 YAWL Editor Man vl doc 46 Acknowledgements Queensland University of Technology Dr Marlon Dum
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