Question about jBPM expression

[johnlz]

Hi,

I am trying now to build a loop execution in my jBPM script. I know that the expression must be used here. But in order to control the amount of the loop, I think a loop-variable is also needed. I don't know how to make the variable reduce. For example, in C/++ we have i=i-1, but in jBPM how can I do this?

My code is written as the following, it works always abnormal. Could somebody please give me some advices? Thanks!

John

<?xml version="1.0" encoding="UTF-8"?>

<process-definition
 xmlns="http://jbpm.org/3/jpdl" name="hello">
 <start-state name="start">
 <task name="task">
 <controller>
 <variable name="MyID" access="read,write" mapped-name="decisionID"></variable>
 </controller>
 </task>
 <transition name="ini" to="decision1">
 <script>
 <expression>executionContext.setVariable("decisionID",new Integer(10))</expression>
 </script>
 </transition>
 </start-state>
 <decision name="decision1">
 <transition name="tr2" to="task1">
 <condition expression="#{contextInstance.variables['decisionID'] gt 0}" />
 </transition>
 <transition name="tr1" to="end1"></transition>

 </decision>
 <task-node name="task1">
 <transition name="" to="decision1">
 <script>
 <expression>executionContext.setVariable("decisionID",Integer.valueOf(Integer.parseInt(executionContext.getVariable("decisionID").toString())-1))</expression>
 </script>
 <action name="HelloWS" class="com.jbay.action.MyActionHandler"></action>
 </transition>
 </task-node>
 <end-state name="end1"></end-state>
</process-definition>

[johnlz]

hi! Nobody can answer my question?

[jpf]

Hi,

might it be possible that the decission node is the issue?
I faced a similar problem (with the current jbpm 3.2 snapshot from CVS) with a node looking like this:

 <decision name="Mitreisende vorhanden?">
 <transition name="ja" to="Weitere Mitreisende angeben"></transition>
 <condition expression="#{contextInstance.variables['isAccompanied'] == true}" />
 </transition>
 <transition name="nein" to="Ende"></transition>
 </decision>

Transition 2 ("nein") was never taken. I changed it to:

 <decision name="Mitreisende vorhanden?">
 <transition name="nein" to="Ende"></transition>
 <transition name="ja" to="Weitere Mitreisende angeben">
 <condition expression="#{contextInstance.variables['isAccompanied'] == true}" />
 </transition>
 </decision>

Now everything is working as expected. In my opinion both solutions should have the same result because the transition without condition should always be true..


Rgds,
Patrick