topic Re: Execution of JavaServiceTask via variable in Alfresco Forum

Execution of JavaServiceTask via variable

anandvivek — Thu, 23 Mar 2017 10:33:57 GMT

Hi, I am trying to execute the service task via variable.When I am using literal in the service task it works. But when I assign the variable with the same literal it doesnt work.CASE 1: Using literal in delegateExpressionBelow is an exampleProcess XML<?xml version="1.0" encoding="UTF-8"?><

Re: Execution of JavaServiceTask via variable

gdharley — Thu, 23 Mar 2017 12:01:37 GMT

A delegateExpression, as the name implies, must implement the JavaDelegate or ActivitiBehavior interface.

Obviously the ${assignee} expression doent resolve to such a class.

I am not sure what your ${assignee} class actually resolves to so cannot offer a solution, but you may consider using an Expression rather than a DelegateExpression.

Thanks,

Greg

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Re: Execution of JavaServiceTask via variable

anandvivek — Thu, 23 Mar 2017 13:13:39 GMT

assignee is my process variable and I have set the value of assignee to "LineManagerCompletionService"

<dataObject id="assignee" name="assignee" itemSubjectRef="xsd:string">
<extensionElements>
<activiti:value>LineManagerCompletionService</activiti:value>
</extensionElements>
</dataObject>

When I put DelegateExpression = ${LineManagerCompletionService}. It works.(Case 1 in my example)

But when I put DelegateExpression = ${assignee} i get this error. (Case 2 in my example)

Basically I want to execute the service task based on process variable value, which can be initialized at the start of process. So that I dont have to create multiple workflow defn only because my service task is different.

Re: Execution of JavaServiceTask via variable

gdharley — Thu, 23 Mar 2017 14:45:39 GMT

Yeah, what you need to do is use the working syntax:

And add the assignee as an input property. Simple enough to do and the users guide has examples as well as the test suite.

Greg

Re: Execution of JavaServiceTask via variable

anandvivek — Fri, 24 Mar 2017 07:47:53 GMT

Hi Greg,

Thanks a lot for reply. Not sure if I explained my problem correctly.

I am NOT trying to do field injection. My problem is quite different.

For e.g. I have more than one Class which implements JavaDelegate.

@Named("LineManagerCompletionService1")
public class LineManagerCompletionService1 implements JavaDelegate {

@Override
public void execute(DelegateExecution execution) throws Exception {
System.out.println("******Saving LM Decision=====1******");
}

}

@Named("LineManagerCompletionService2")
public class LineManagerCompletionService2 implements JavaDelegate {

@Override
public void execute(DelegateExecution execution) throws Exception {
System.out.println("******Saving LM Decision=====2******");
}

}

@Named("LineManagerCompletionService3")
public class LineManagerCompletionService3 implements JavaDelegate {

@Override
public void execute(DelegateExecution execution) throws Exception {
System.out.println("******Saving LM Decision====3******");
}

}

And I want to execute any of the different beans(bean name can be provided as input parameter at start of the workflow) from same JAVA Service tasks without modifying my process defn.

I hope this makes this clear now. Also can you please point me where its exactly mentioned in User Guide?

Re: Execution of JavaServiceTask via variable

gdharley — Fri, 24 Mar 2017 14:49:16 GMT

Wow, interesting approach.

I haven't tested it, but from your description I do believe this approach should actually work.

Make sure the Object associated with the variable is actually the bean and not simply the name of the bean. If it is just the name of the bean the expression will resolve a string type and you will get the error you are seeing.

If it is the actual bean : execution;setVariable("assignee", myBean);

Then I dont see why this doesnt work.

Greg