Process-state: can't create a process instance when processD

[ayang]

I'm trying a very simple example of sub-processes up and running with the following definitions:

<process-definition xmlns="urn:jbpm.org:jpdl-3.1" name="sub">
 <start-state name="start">
 <transition name="" to="node"></transition>
 </start-state>
 <node name="node">
 <transition name="" to="wait-state"></transition>
 </node>
 <end-state name="end"></end-state>
 <state name="wait-state">
 <transition name="" to="end"></transition>
 </state>
</process-definition>

<process-definition xmlns="urn:jbpm.org:jpdl-3.1" name="caller">
 <start-state name="start">
 <transition name="" to="node"></transition>
 </start-state>
 <end-state name="end"></end-state>
 <node name="node">
 <transition name="" to="call sub"></transition>
 </node>
 <process-state name="call sub">
 <sub-process name="sub"/>
 <transition name="" to="end"></transition>
 </process-state>
</process-definition>

Excerpted from my unit test code:

 context = _jbpmConfiguration.createJbpmContext();

 FileInputStream fis_sub = new FileInputStream("processes/sub/processdefinition.xml");
 FileInputStream fis_caller = new FileInputStream("processes/caller/processdefinition.xml");

 ProcessDefinition pdload_sub = ProcessDefinition.parseXmlInputStream(fis_sub);
 ProcessDefinition pdload_caller = ProcessDefinition.parseXmlInputStream(fis_caller);

 context.deployProcessDefinition(pdload_sub);
 context.deployProcessDefinition(pdload_caller);

 GraphSession gs_caller = context.getGraphSession();

 // don't think I necessarily need to reload the process definitions
 // from the session but it doesn't make a difference
 ProcessDefinition pd_sub = gs_caller.findLatestProcessDefinition("sub");
 ProcessDefinition pd_caller = gs_caller.findLatestProcessDefinition("caller");

 ProcessInstance inst = new ProcessInstance(pd_caller);

 // begin
 Token token = inst.getRootToken();
 ContextInstance contextInst = (ContextInstance) inst.getInstance(ContextInstance.class);

 System.out.println("getNode().getName(): " + token.getNode().getName());

 token.signal();
 System.out.println("getNode().getName(): " + token.getNode().getName());
 }
 finally
 {
 context.close();
 }

The process runs successfully until it tries to invoke the sub-process (when I signal the calling process) at which point I get the NullPointerException

I'm sure it's something very simple - any thoughts?

Thanks,
Andy

[saviola]

Hi, ayang!
I think the problem arises from the fact that the subprocess is not actually in the database before you close the jbpmContext.
Try and investigate in that direction.

Regards,
Saviola

[ayang]

I am deploying both processes (with the sub-process getting deployed first):

 context.deployProcessDefinition(pdload_sub);
 context.deployProcessDefinition(pdload_caller);

Shouldn't deploying the processes put them into the "database"? Mind you, I'm using the in-memory HSQL db and a static JbpmConfiguration parsed from an XML string (cut and pasted from sample code). I'm not sure if there is something I have mis-configured?

Thanks,
Andy

[ayang]

Found the problem.

The clue was after executing the following block:

ProcessDefinition pdload_sub = ProcessDefinition.parseXmlInputStream(fis_sub);
ProcessDefinition pdload_caller = ProcessDefinition.parseXmlInputStream(fis_caller);

context.deployProcessDefinition(pdload_sub);
context.deployProcessDefinition(pdload_caller);

I saw the following message when parsing the process definition xml for the "caller" process.

DEBUG ProcessState : subprocess for process-state 'call subby' not yet bound

Looks like the process and sub-processes get bound at parse-time rather than deploy-time.

This did the trick:

ProcessDefinition pdload_sub = ProcessDefinition.parseXmlInputStream(fis_sub);
context.deployProcessDefinition(pdload_sub);

ProcessDefinition pdload_caller = ProcessDefinition.parseXmlInputStream(fis_caller);
context.deployProcessDefinition(pdload_caller);