Hi,
I have a workflow where I need a fork and one of the paths is readonly. For example, when a student submits a request to a teacher for a leave, he needs to get the task in "Leaves awaiting approval" list, (He cant change anything though). For this we wrote a custom join node, which does the joining, and also terminates all readonly tasks in the parent token (Apologies, for posting a slightly big xml file, but I couldnt make it any simpler to demonstrate my point)

<task-node name="Student Submits Leave">
 <task name="Create Leave Request" swimlane="student"/>
 <transition name="fork1" to="Fork Leave Request"/>
</task-node>

<fork name="Fork Leave Request">
 <transition name="Read Only" to="Leaves sent to teacher"/>
 <transition name="Read Write" to="Pending Approval"/>
</fork>

<task-node name="Leaves sent to teacher">
 <task name="Leave requests sent to teacher" swimlane="student"/>
 <!-- The UI will just show a readonly jsp page-->
 <transition name="" to="JoinStudent"/>
</task-node>

<task-node name="Pending Approval">
 <task name="Pending Approval" swimlane="teacher"/>
 <!-- Teacher can approve/send to principal-->
 <transition name="" to="JoinStudent"/>
</task-node>

<custom-join name="JoinStudent"> <!-- This will terminate the read only token -->
 <transition name="" to="Principals Review"/>
</custom-join>

<task-node name="Principals Review">
 <task name="Principals Review" swimlane="principal"/>
 <!-- Teacher can approve/send to principal-->
 <transition name="" to="Pending Approval"/>
</task-node>

So a principal reviews the request from the teacher, and if he finds it ok, sends again to the principal, so that he can do a final approval (those parts are not shown here)
a) The node ("Pending Approval") has to be exactly the same, whether the request is coming from student for first time, or if it is coming from the principal
b) Now when the first time join is invoked, i am setting token.setAbleToReactivateParent as false meaning the token cannot do a join anymore :), so when the same token is coming back from principal, the workflow stops there.

To avoid this, we added an else clause

 public void execute(ExecutionContext executionContext) {
 Token token = executionContext.getToken();
 if (token.isAbleToReactivateParent()) {
 Token parentToken = token.getParent();
 if (parentToken != null) {
 //go ahead and terminate all sibling tasks
 } else {
 logger.debug("Token[" + token + "] is itself a parent");
 //This is the case of the token coming from principal
 leave(executionContext);
 }
 }
 }

I would like to know, if there is someone who has encountered a similar issue, If yes, is there a recommendation for this. I went through the code, in Join class of JBPM and there is no else part there. The essence is that you dont expect a Join call when there is no fork, for me there is a node, which could have come as a result of a fork and in some cases it might not be from a fork (in this case from principals review node)