use something like this with JBPM5.4
java.util.Map<String, Object> result = new java.util.HashMap<String, Object>(); result.put("Result", action); org.jbpm.task.service.ContentData contentData = org.jbpm.task.utils.ContentMarshallerHelper.marshal(result, null); taskService.complete(taskId, userId, contentData);
This is a good idea, and I have already tried it. But if you look at the error stack trace, you see that completeWithResults() calls complete(), which calls the marshaller another time and makes the error. So the same problem happens.
if someone has the same problem, I found the solution:
I was using: