public void interruptAll(){
synchronized (knownActorTasks) {
    for (    Future<Void> ft : knownActorTasks) {
      ft.cancel(true);
    }
    threadGuard.interruptAll();
  }
}

public void interruptAll ( ) { synchronized ( knownActorTasks ) { for ( Future < Void > ft : knownActorTasks ) { ft . cancel ( true ) ; } threadGuard . interruptAll ( ) ; } }
ensure that any guarded regions are interrupted .
