topic Re: signalEventReceived & local variables in Alfresco Archive

signalEventReceived & local variables

fritz128 — Thu, 05 Sep 2013 12:03:24 GMT

I launch many subrocess by command:for (int i = 0; i < count; i++) { signalEventReceived(signalName, executionId, subprocessVars);}‍‍‍‍‍I can't use multi-instance because I doesn't know the amount of subprocesses and I have to launch new subprocess on user request. Problem:Each subprocess contai

Re: signalEventReceived & local variables

fritz128 — Thu, 05 Sep 2013 13:53:20 GMT

Sorry, there is mistake in code above. It should looks like:
<java>
for (int i = 0; i < count; i++) {
runtimeService.signalEventReceived(signalName, executionId, subprocessVars);
}
</java>

Re: signalEventReceived & local variables

trademak — Thu, 05 Sep 2013 15:07:07 GMT

Are you sending signal events in the same process instance? Could you explain a bit more the background of what you are trying to achieve?

Best regards,

Re: signalEventReceived & local variables

fritz128 — Fri, 06 Sep 2013 06:33:50 GMT

Yeah, I send signal events in the same process instance.
My workflow:
I have some global process, for example, car lottery. This process starts when manager push "Start Lottery" button. He can start many loterries simultaneously.
To participate in this lottery user should go throught several stages of registration, attend on lottery, take a price (big or small, little price gives to all participants), and so on. So this task need to be moved to separate subprocess.

My code & problem:
So, I don't know how many users will participate in lottery, I need to start subprocesses in for-loop:
<java>
//this handler proceed launching users's subprocesses for current lottery
public void handler(int loterryId, List<Integer> userIds) {
….
Map<String, Object> subprocessVars = null;
for (Integer userId : userIds) {
    subprocessVars = new HashMap<String, Object>();
    subprocessVars.put("lotteryId", lotteryId);
    subprocessVars.put("vacancyId", vacancyId);
    //PROBLEM: subprocessVars is written to global context, and if will be overriden by each subprocess!
    runtimeService.signalEventReceived(signalName, executionId, subprocessVars);
}
}
</java>

Re: signalEventReceived & local variables

trademak — Fri, 06 Sep 2013 08:19:21 GMT

I do need some more information. You say you have a sub process, but is it really? Is it an embedded sub process part of the global process or do you have a signal start event in a separate process definition? A process picture would help a lot to understand what you are trying to do.

Best regards,

Re: signalEventReceived & local variables

fritz128 — Fri, 06 Sep 2013 09:03:27 GMT

Yeah, I use embedded subprocess. Yes, embedded subprocess is a part of main process definition. My workflow
[img=http://s2.postimg.org/ioq6jynp1/Process.jpg]

My xml process definition
<code>
<signal id="participanSubprocess" name="participanSubprocess"/>
<process id="lotteryProcess"
….
<userTask id="findParticipants" name="Find participants"/>
<boundaryEvent id="launchSubprocess" attachedToRef="findParticipants" cancelActivity="false">
     <signalEventDefinition signalRef="participanSubprocess"/>
</boundaryEvent>
   ……
<subProcess id="participanSubprocess">
     …….
</subProcess>
</process>
</code>

Re: signalEventReceived & local variables

trademak — Fri, 06 Sep 2013 14:58:33 GMT

I think a signal event is not the right approach for this. Why don't you start a separate sub process with a call activity or a Java service task if more custom logic is required? Then every sub process has its own context.

Best regards,

Re: signalEventReceived & local variables

fritz128 — Mon, 09 Sep 2013 09:56:06 GMT

I have find no way to launch callActivity on user request. For example today user say: launch 3 subprocesses, tomorrow he will say: launch two additional subrocesses for current process and so on.
Can I lauch callActivity on event?

Re: signalEventReceived & local variables

trademak — Fri, 13 Sep 2013 09:00:23 GMT

Yes if you add an event sub process you can.

Best regards,

Re: signalEventReceived & local variables

fritz128 — Sat, 14 Sep 2013 18:37:43 GMT

Yeah, but there are two essential points (from docummentation):
1. Activiti only supports interrupting Event Sub-Processes.
2. Activiti only supports Event Sub-Process triggered using an Error Start Event or Message Start Event.

As I understand, in my case that are drawbacks:
1. Interrupting means that when I start event subprocess from "find participants"-task, the "find participants"-task be completed (destroied).
2. Only message start event. I don't use JMS or something like it in my app. Ass I understand, the responsibility for delivering message lays on me, and I haven't any desire to use JMS.

Am I right about drawbacks above?

Re: signalEventReceived & local variables

trademak — Mon, 16 Sep 2013 07:40:59 GMT

1. That's correct
2. No JMS has nothing to do with a message event. A message event works with logical messages and you can just invoke the Activiti API to send a message to the Engine, without needing something like JMS.

Best regards,

Re: signalEventReceived & local variables

fritz128 — Mon, 16 Sep 2013 09:31:21 GMT

And maybe the last question (it is very important):
You've said that my first statement is right (about interrupting). But I need my main process wait untill finish of all event subprocesses.
Does it mean that event subprocess is not appropriate to me?

Re: signalEventReceived & local variables

trademak — Tue, 17 Sep 2013 09:56:33 GMT

Yes, the event sub process will end any running execution, so it might not be appropriate for you.

Best regards,