buncher.tell(new SetTarget(probe.ref()), ActorRef.noSender());
buncher.tell(new Queue(1), ActorRef.noSender());
buncher.tell(new Queue(2), ActorRef.noSender());
buncher.tell(flush, ActorRef.noSender());
buncher.tell(new Queue(3), ActorRef.noSender());
final Batch b = probe.expectMsgClass(Batch.class);
assert b.objects.size() == 2;
assert b.objects.contains(1);
assert b.objects.contains(2);
}