could you post the start-node and corresponding parts of the swimlane?
If you use an expresssion attribute on th e swimlane, the getActorIdExpression and getPooledActorsExpression are indeed null. If you use the actor-id attribute or the pooled-actors attribute either of them will not be null.
I've been looking at how to get access to the expression attribute via the API but found nothing (yet). Passed this on to the developers.
btw, if there is no instance, there is no assigned user. There only is a 'user to be assigned'
I was under the impression that if I set the expression to user(buyer) for example, then the actorIdExpression would be "buyer" as this makes sense. I have to say, the docs on all this stuff are very lacking. There's so many posts asking for something fairly simple which jBPM can do but its just hard to find. The designer doesn't show a lot of the useful attributes and features that are possible directly in the source.
Both the swimlane and start node are very simple:
<swimlane name="buyer"> <assignment expression="user(buyer)"></assignment> </swimlane>
<start-state name="bought"> <task name="bought task" swimlane="buyer"> <controller> <variable name="manufacturer" access="read,write,required"></variable> <variable name="name" access="read,write,required"></variable> </controller> </task> <transition name="copy into db table" to="arrives"> <action name="db copy" class="action.BoughtActionHandler" config-type="bean"></action> </transition> </start-state>
the assignment can also have an actor-id attribute or a pooled-actorid (see the docs) these two are accessible via the api. The expression seems not to be accessible.
Maybe you should file a jira issue for this.