(jbpm:3.0.2)
Hi there,
I have following use case:

+----+
 |Fork|
 +----+
 / \
 +--------+ +-------+
 |State A | |State B|
 +--------+ +-------+
 \ /
 +-----+
 |Join |
 +-----+

Now I want to execute all 4 possible cases:
A B
0 0: execute none of the (task)nodes, proceed with join
0 1: execute only State B
1 0: execute only State A
1 1: execute both States

There are controller variables in the context that decide whether the state should be executed or not.

So I tried a simple conditioned transition:

<fork name="fork1>
 <transition name="toStateA" to="State A">
 <script>
 <expression>isStateA.booleanValue()</expression>
 </script>
 </transition>
 <transition name="toStateB" to="State B">
 <script>
 <expression>isStateB.booleanValue()</expression>
 </script>
 </transition>
 </fork>

But the beanshell scripts dont get considered and it forks into both transitions.
When you throw a look on the Fork class:

public void execute(ExecutionContext executionContext) {
 Token token = executionContext.getToken();
 Node forkNode = token.getNode();

 // phase one: collect all the transitionNames
 Collection transitionNames = null;
 List forkedTokens = new ArrayList();

 // by default, the fork spawns a token for each leaving transition
 if (script==null) {
 transitionNames = forkNode.getLeavingTransitionsMap().keySet();

 } else { // a script is specified
 // if a script is specified, use that script to calculate the set
 // of leaving transitions to be used for forking tokens.
 Map outputMap = script.eval(token);
 if (outputMap.size()==1) {
 Object result = outputMap.values().iterator().next();
 if (result instanceof Collection) {
 transitionNames = (Collection) result;
 }
 }
 if (transitionNames==null) {
 throw new RuntimeException("script for fork '"+name+"' should produce one collection (in one writable variable): "+transitionNames);
 }
 }
...

You see, that there has to be directly a script under the fork-node, and that script has to have a list of the transition names as output.

Ok, I could bybas this trouble by using several decision nodes (in this case 1 with 4 leaving Transition: ->A, ->B, ->fork, ->the node after the join), but if have more than 2 childs, it would quickly get very complicated.

So, what do you recommend? Maybe its still possible with the the current (3.0.2) API/JPDL, maybe I missed some point.