final InternalAgenda agenda = (InternalAgenda) ksession.getAgenda();
final Boolean[] filtered = new Boolean[]{false};
ksession.addEventListener(new DefaultAgendaEventListener() {
public void activationCancelled(ActivationCancelledEvent event,
WorkingMemory workingMemory) {
if (event.getCause() == MatchCancelledCause.FILTER) {
filtered[0] = true;