How to get all childelements (JavaDelegate, Camunda BPM Reactor)

Camunda 7 Topics Discussion & Questions
1

Hello Community,

hopefully you can help me. I want to get all child elements (all of the following bpmn elements of the current process definition (type: User Task)) at the position of the current User Task where my UserTaskListener is located and called. How can I do this?
I tried to use the getChildElementsByType() method but there is no result?
I am using the Camunda BPM Reactor and an UserTaskListener which is called when an User Task is completed.

Collection taskChildElementUT = delegateTask.getBpmnModelElementInstance().getChildElementsByType(UserTask.class);
for (UserTask userTask : taskChildElementUT) {
System.out.println("Child elements ‘User Task(s)’: "+ userTask.getName());
}

Or do I need to take another method to get all of the following bpmn elements (type: User Task) after the UserTaskListener has been called?

Thanks a lot!

Regards,
Paul

2

Hi Paul,

#getChildElementsByType returns all child elements in the XML sense, so it doesn’t help you. You can access all nodes that follow a certain node as follows:

UserTask userTask = modelInstance.getModelElementById("foo");
Collection<SequenceFlow> outgoingSequenceFlows = userTask.getOutgoing();

outgoingSequenceFlows.forEach(f -> {
  FlowNode nextFlowNode = f.getTarget();

  if (nextFlowNode instanceof UserTask)
  {
    // do something
  }
});

You can do this repeatedly to traverse the process graph. Just be aware that you may have to watch out for infinite loops in your process model.

Cheers,
Thorben

3

Hi Thorben,

thanks a lot for your answer. I will implement an algorithm with your advice above. Looks good and makes sence.

Best regards,
Paul

4