Diagram not updated (using async. work item)

[liviah]

Hi All,

last weekend I played arround with drools (5.3.0.CR1) and  jbpm (5.1.1.Final) on jboss 5.1.

I have a simple bpmn:

[1]start -> [2] timer ->[3]script -> [4]AsyncHandler -> [5]timer -> [6]script -> [7]end

After my AsyncHandler calls completeWorkItem task [5] and [6] will executed. But if I take a look at the diagram task [4] is still highlighted.

How I can make shure a user will see right/updated diagram?

My WorkHandler to test a asynch behavior:

public class AsyncWorkItemHandler implements WorkItemHandler {

     StatefulKnowledgeSession ksession;

    public AsyncWorkItemHandler(ProcessContext kcontext){

        super();

        this.ksession = (StatefulKnowledgeSession)kcontext.getKnowledgeRuntime();

    }

    public AsyncWorkItemHandler(StatefulKnowledgeSession ksession) {

        super();

        this.ksession = ksession;

   @Override

   public void executeWorkItem(WorkItem workItem, WorkItemManager manager){

        class WThread extends Thread{

            int sessionId;

            long itemId;

            KnowledgeBase kbase;

            Environment env;

            public WThread(int sessionId,  long itemId,

                    KnowledgeBase kbase, Environment env) {

                super();

                this.sessionId = sessionId;;

                this.itemId = itemId;

                this.kbase = kbase;

                this.env = env;

            }

            @Override

            public void run(){

                int seconds = 30;

                System.out.println("thread for session " + this.sessionId + " (workitem "+ this.itemId +"), sleep " + seconds + "s");

                try {

                    Thread.currentThread().sleep(seconds * 1000);

                } catch (InterruptedException e) {

                    e.printStackTrace();

                }

                StatefulKnowledgeSession ksession = JPAKnowledgeService.loadStatefulKnowledgeSession(this.sessionId, kbase, null, env);

                ksession.getWorkItemManager().registerWorkItemHandler("AsyncTask", new AsyncWorkItemHandler(ksession));

                ksession.getWorkItemManager().completeWorkItem(this.itemId, null);

                System.out.println("thread for session " + this.sessionId + " (workitem "+ this.itemId +") end");

                this.clean();

            }

               protected void clean(){

                   this.kbase = null;

                   this.env = null;

            }

        }

        KnowledgeBase kbase = ksession.getKnowledgeBase();

        Environment env = ksession.getEnvironment();

        int sessionId = ksession.getId();

        long itemId = workItem.getId();

        WThread t = new WThread(sessionId, /*processId,*/ itemId, kbase, env);

        t.start();

      }

    }

}

Any hints?

Many thx + greetings,

Livia

[tsurdilovic]

I don't really undertand why you are doing the Wthread stuff in executeWorkItem method. Typically you can just complete the workitem with:

manager.completeWorkItem(workItem.getId(), null);

Here is chapter of the docs that may help: http://docs.jboss.org/jbpm/v5.1/userguide/ch13.html#d0e3599.

Thanks.

[liviah]

Hi Tihomir,

I need a async work item handler. I have to call a external system and wait for a long time to got a response message. If I got a response i have to load the statefull session and call completeWorkItem. Therefor I don't use "manager" directly.  WThread is only a dummy for tesing jbpm in a sync behavior....

heartfelt greetings,

Liv

[tsurdilovic]

Ok, that's one way of doing it, but typically not recommended. Take a look at the human task handlers in jBPM, for example AsyncWSHumanTaskHandler. Those implementations are alot closer to reality. In your example I still think you need to call manager.completeWorkItem in order to advance.

Thanks.

[timothyhahn]

Did you ever resolve your problem, I'm trying to do the same thing.