Proper way to set or update JBPM6 Process Variables

Question

I am trying to set the process variable but getting below error

java.lang.IllegalStateException: Process instance 10[SampleBusinessProcess] is disconnected.
at org.jbpm.process.instance.impl.ProcessInstanceImpl.getProcess(ProcessInstanceImpl.java:100)
at org.jbpm.workflow.instance.impl.WorkflowProcessInstanceImpl.setVariable(WorkflowProcessInstanceImpl.java:343)

Here is my code -

ProcessInstance processInstance = runtimeEngine.getKieSession().getProcessInstance(processInstanceId);
((WorkflowProcessInstanceImpl) processInstance).setVariable("myvariable", "myvalue");

Please help me with the best way to set the process variable.

Thanks.

Answer 1

I would recommend to use the jbpm-services for interacting with the engine, this offers an operation to set a variable: https://github.com/kiegroup/jbpm/blob/7.7.0.Final/jbpm-services/jbpm-services-api/src/main/java/org/jbpm/services/api/ProcessService.java#L223

Alternatively, if you make sure that your code is executed in the same transaction (by for example starting and committing the transaction yourself, around the code you currently have), you will be able to set the variable this way, as the process instance will only disconnect as soon as the transaction commits.

Answer 2

I can't comment on the previous answer so I'm posting this answer.

The quick and dirty way I found (inspired from previous answer) is:

public void setProcessInstanceVariables(long processInstanceId, Map<String, Object> variables) {
    kieSession.execute(new SetProcessInstanceVariablesCommand(processInstanceId, variables));
}

Thanks a lot Kris Verlaenen!