@SuppressWarnings("unchecked")
public void execute(PvmExecutionImpl execution) {
// calculate the propagating execution
PvmExecutionImpl propagatingExecution = null;
ActivityImpl activity = execution.getActivity();
// if this transition is crossing a scope boundary
if (activity.isScope()) {
PvmExecutionImpl parentScopeInstance = null;
// if this is a concurrent execution crossing a scope boundary
if (execution.isConcurrent() && !execution.isScope()) {
// first remove the execution from the current root
PvmExecutionImpl concurrentRoot = execution.getParent();
parentScopeInstance = execution.getParent().getParent();
log.fine("moving concurrent "+execution+" one scope up under "+parentScopeInstance);
List<PvmExecutionImpl> parentScopeInstanceExecutions = (List<PvmExecutionImpl>) parentScopeInstance.getExecutions();
List<PvmExecutionImpl> concurrentRootExecutions = (List<PvmExecutionImpl>) concurrentRoot.getExecutions();
// if the parent scope had only one single scope child
if (parentScopeInstanceExecutions.size()==1) {
// it now becomes a concurrent execution
parentScopeInstanceExecutions.get(0).setConcurrent(true);
}
concurrentRootExecutions.remove(execution);
parentScopeInstanceExecutions.add(execution);
execution.setParent(parentScopeInstance);
execution.setActivity(activity);
propagatingExecution = execution;
// if there is only a single concurrent execution left
// in the concurrent root, auto-prune it. meaning, the
// last concurrent child execution data should be cloned into
// the concurrent root.
if (concurrentRootExecutions.size()==1) {
PvmExecutionImpl lastConcurrent = concurrentRootExecutions.get(0);
if (lastConcurrent.isScope()) {
lastConcurrent.setConcurrent(false);
} else {
log.fine("merging last concurrent "+lastConcurrent+" into concurrent root "+concurrentRoot);
// We can't just merge the data of the lastConcurrent into the concurrentRoot.
// This is because the concurrent root might be in a takeAll-loop. So the
// concurrent execution is the one that will be receiving the take
concurrentRoot.setActivity(lastConcurrent.getActivity());
concurrentRoot.setActive(lastConcurrent.isActive());
lastConcurrent.setReplacedBy(concurrentRoot);
lastConcurrent.remove();
}
}
} else if (execution.isConcurrent() && execution.isScope()) {
log.fine("scoped concurrent "+execution+" becomes concurrent and remains under "+execution.getParent());