topic Re: Setting process variable at run time in Alfresco Archive

Setting process variable at run time

niyas_m — Tue, 26 Jul 2016 12:42:30 GMT

Hi, I am new to Activiti . I would like to know how to set process variables to an existing process instance ( already instantiated ) at run time. The use case to provide condition value for an exclusive gateway following an user task completion . I tried the following methods . 1. runtimeService.

Re: Setting process variable at run time

hari — Wed, 27 Jul 2016 11:40:19 GMT

Hi,

If you use service task you can set the process variables there.
<code>
public void execute(DelegateExecution execution) throws Exception {
execution.setVariable("<VariableName>",<VariableValue>);
}
</code>

You can set them similarly in script task also.

Re: Setting process variable at run time

hari — Wed, 27 Jul 2016 11:42:33 GMT

I also think setting the variables map while completing a task should also work.

Re: Setting process variable at run time

niyas_m — Wed, 27 Jul 2016 11:47:34 GMT

Hi Hari,

Thanks for the idea. Will try it

Thanks
Niyas

Re: Setting process variable at run time

niyas_m — Wed, 27 Jul 2016 11:49:47 GMT

Hari,

I tried this way as option # 2 mentioned in my original post. But unfortunately its not working . Values supplied as part of task completion is not carried over to the exclusive gateway for its conditional navigation.

Thanks
Niyas

Re: Setting process variable at run time

jbarrez — Wed, 27 Jul 2016 12:10:51 GMT

> Both are not working .

What do yo mean? Those two option do that, they set the variables.
How did you verify that the variables were not set?

A small bit of test code would to understand what's happening here.

Re: Setting process variable at run time

niyas_m — Wed, 27 Jul 2016 13:02:43 GMT

Hi Barrez,

PFA the test code and the bpmn xml files for your review

Thanks
Niyas

Re: Setting process variable at run time

niyas_m — Thu, 28 Jul 2016 06:00:43 GMT

Hi Barrez,

The same process and test code is working when i use "sub process" instead of "call activity" . But ideally we will need to separate the business processes into different bpmn files . Please advise why the stuff that works with sub process is not working with call activity. Variable scope constraints ?.
Any solution to make it work with call activity ? .

Thanks
Niyas

Re: Setting process variable at run time

jbarrez — Thu, 28 Jul 2016 09:48:59 GMT

Haven't looked at the xml but,

> The same process and test code is working when i use "sub process" instead of "call activity"

Call activity _do not_ inherit variables like subprocesses.
You need to explicitly map variables in and out for call activities (checks the docs on call activity)

Re: Setting process variable at run time

niyas_m — Thu, 28 Jul 2016 11:01:14 GMT

Hi Barrez ,

   Thanks for the update.

   Yes , i have mapped the variables in call activity. ( sourceExpression="${action}" target="action" ) .
   Issue i am facing using call activity is , the value for the variable is reaching the X-OR gateway only when i declare them as part of process instance creation. (setting through run time service or task completion is not working) .

But , i could do it through a service / script task .I am still wondering why the below methods are not working with call activity as it would have made the execution simple without service / script tasks elements

1. runtimeService.setVariable(processInstance.getId(),"variable","value");
2. taskService.complete(tasks.get(0).getId(), vars);

Thanks
Niyas

Re: Setting process variable at run time

jbarrez — Fri, 29 Jul 2016 08:28:00 GMT

Okay, I looked at your test.
The reason is because a call activity _is_ actually a real process instance (it will show up in queries as such).
Hence, when you set your variable

runtimeService.setVariable(pi.getId(), "action", "task2");

You're setting it on the main process, not on the new started process.
Add the following line and it will work:

ProcessInstance newProcessInstance = runtimeService.createProcessInstanceQuery().superProcessInstanceId(pi.getId()).singleResult();
runtimeService.setVariable(newProcessInstance.getId(), "action", "task2");

Re: Setting process variable at run time

niyas_m — Sun, 31 Jul 2016 05:56:16 GMT

Hi Barrez,

Thanks for the solution. Will try as suggested

Regards
Niyas