as I pointed out, the problem is not because the returned active process instance null, but because it is not completely initialized.
The exception happens in the following method of the class org.jbpm.process.instance.impl.ProcessInstanceImpl:
| public Process getProcess() { |
| | if (this.process == null) { |
| | this.process = kruntime.getKnowledgeBase().getProcess(processId); |
| | } |
| | return this.process; |
| } |
The kruntime is null.
I hope, now the problem is clearly and completely described.