Task Listener Implementation - How to interrupt execution?

I have a custom TaskListener defined as ‘Class’ in the modeler and fired on a ‘complete’ event of a user task.

The method ‘notify’ cannot throw Exceptions, so I cannot stop execution of something is not right.

In this very case I wish to check if all input parameters were correctly set and stop execution if any condition is not met.

If the taskListener is not the right place to do that, I could with an Execution Listener but I will certainly lose the task assignee and other task properties for example, unless I can query the execution to track down the latest completed task and get its properties.

Hi @Mizar01,

I think your case is identical to the example in below link


In case you need to explicitly model errors, then see below example


The documentation you suggested helped me to understand that technical errors should not be treated as a bpmn error.

And this is the case, sorry if I wasn’t clear: I don’t want to check if someone missed or mispelled something in the user task. I want to forbid the process to proceed further if the bpmn definition is not completed with all the desired arguments passed to delegation code.
For example i wish to throw exception from the taskListener if the task doesn’t have ‘var1’ as input variable (in the input tab of the modeler).
I have a lot of user tasks and the least I would like do is to interrupt execution if something is internally missing during java calls. I cannot apply bpmn xor gates or boundary events for every single task.

Xor gates and boundary events should be used only for meaningful bpmn flow events.

Hi @Mizar01
You can throw ProcessEngineException.

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