Given the following process definition:

<?xml version="1.0" encoding="UTF-8"?>
<process-definition xmlns="urn:jbpm.org:jpdl-3.2" name="Complex">
<description>
Complex description
</description>
<start-state name="start-state1">
<transition to="task-node1"></transition>
</start-state>
<task-node name="task-node3">
<task name="Task3_1">
<assignment actor-id="1"></assignment>
</task>
<transition to="end-state1"></transition>
</task-node>

<node name="node1">
<transition to="task-node3"></transition>
</node>

<join name="join1">
<transition to="node1"></transition>
</join>

<fork name="fork1">
<transition to="task-node2"></transition>
<transition to="node2" name="to node2"></transition>
<transition to="state1" name="to state1"></transition>
</fork>

<task-node name="task-node2">
<task name="Task2_1">
<assignment actor-id="1"></assignment>
</task>
<task name="Task2_2">
<assignment actor-id="1"></assignment>
</task>
<transition to="join1"></transition>
</task-node>

<task-node name="task-node1">
<task name="Task1_1">
<assignment actor-id="1"></assignment>
</task>
<transition to="fork1"></transition>
</task-node>

<node name="node2">
<transition to="end-state2"></transition>
</node>

<state name="state1">
<transition to="end-state2"></transition>
</state>

<end-state name="end-state1"></end-state>

<end-state name="end-state2"></end-state>
</process-definition>

Try to do this:

• create a process instance and start it
• a Task1_1 instance is created: end it
• the root token halts at the fork and three children tokens are created
  1) the first causes the creation of a Task2_1 instance and of a Task2_2 instance
  2) the second halts at the state1 state
  3) the third dies at the end-state2 state

Now, there are two cases:

CASE A)

• signal the second token: it then goes on and dies at end-state2 state
• end Task2_1 and Task2_2 instances so that the first token goes on and reaches the join
• now, the root token is restored and goes through node1 and task-node3 nodes, causing the creation of a Task3_1 instance
  This is what I would expect!

CASE B)

• end Task2_1 and Task2_2 instances so that the first token goes on and reaches the join
• signal the second token: it then goes on and dies at end-state2 state
• now, the root token is ended, halting the process instance!
  This is not the expected behaviour, as I would expect that the root token is restored because now all the sibling tokens of those that have reached the join node are ended, so the parent token (= the root token) should be restored and should continue to node1 and subsequent nodes.
  Moreover, I would not expect that the behaviour is different depending on the ordering of the actions "signal the state1 token" and "signal the task-node2 token".

My suspect is this: in case B) the join node is not "triggered" anymore after Task2_1 and Task2_2 are ended, so it can't restore the parent node. Moreover, when the second children token is signalled, it reaches end-state2: jBPM then realizes that all of the sibling tokens are also ended, so it wrongly decides that the parent token should also be ended.