topic Re: Get Previous Task Information in Alfresco Archive

Get Previous Task Information

muratto12 — Mon, 14 May 2012 05:39:24 GMT

Hi,How can I get previous task's Id or Information on a task? (by a execution listener, etc.) Thanks

Re: Get Previous Task Information

nils1 — Tue, 15 May 2012 08:15:02 GMT

Hi, can you elaborate on what exactly you are looking for? You might be looking for the HistoryService.

Cheers,
Nils

Re: Get Previous Task Information

muratto12 — Tue, 15 May 2012 09:54:53 GMT

Users want to see who completed the previous task.

Re: Get Previous Task Information

trademak — Tue, 15 May 2012 14:54:08 GMT

Hi,

As Nils said, this can be done via the HistoryService.
Just look in the Javadoc for more details.

Best regards,

Re: Get Previous Task Information

muratto12 — Tue, 15 May 2012 16:04:16 GMT

Hi,

I'll try it with HistoryService.

Also, how would history service behave in these 2 scenarios.

1. a multi instance task as a first step, and a task as a second step
2. two tasks joined at a paralel gateway as a first step, and a task as a second step

What would be the previous task in these cases. There are not only one previous task in these cases.

Thanks

Re: Get Previous Task Information

muratto12 — Thu, 17 May 2012 07:18:11 GMT

I added a sample diagram for the second situation.

Which one would be the previous task at User Task 3 according to the historyService

Re: Get Previous Task Information

chris_joelly — Fri, 18 May 2012 14:59:36 GMT

i think u need to give the HistoryService a hint on what could be the previous task connected to the task where u want to get the information, because a process instance can have many execution paths which do not nessessarily lead to your user task 3.

i use the following to get the task which was cancelled using a timer boundary listener when the sequence flow is taken via a execution listener on the sequence flow:


@Named
@Stateless
public class EscalationListener {

 @Inject
 HistoryService historyService;

 public void escalate(DelegateExecution execution, String otherTaskId)
   throws Exception {

  HistoricTaskInstance task = historyService
    .createHistoricTaskInstanceQuery()
    .processInstanceId(execution.getProcessInstanceId()).
    .taskDefinitionKey(otherTaskId).singleResult();

                // do some stuff with the task
 }
}


<sequenceFlow id="flow13" name="" sourceRef="boundarytimer1" targetRef="servicetask2">
      <extensionElements>
        <activiti:executionListener event="take" expression="#{escalationListener.escalate(execution, 'usertask2')}"></activiti:executionListener>
      </extensionElements>
</sequenceFlow>

The task to which the boundary timer is attached to is 'usertask2' and for this i want to get the task instance of the running process instance.

In your case u will need to give all your task ids (usertask1, usertask2, …) to the executionListener expression and within the execution listener u can use the history service to get their task end time with task.getEndTime() and decide which one u want to work with, e.g. by putting all task instances in a list and use a comparator based on the end date to sort them to your needs…

hth

Re: Get Previous Task Information

muratto12 — Mon, 21 May 2012 04:01:17 GMT

Thank you very much for answers.