@Test
public void sendingCoffeeFinishedShouldInExceptionIfCaffeineLimitExceeded() {

  new JavaTestKit(system) {{
    ActorRef guest = system.actorOf(Guest.props(system.deadLetters(), new Coffee.Akkaccino(), duration("100 millis"), -1));
    eventFilter(this, Guest.CaffeineException.class, "", 1, () -> {
      guest.tell(Guest.CoffeeFinished.Instance, ActorRef.noSender());
    });
  }};
}