@Test
public void Should_enqueueMessageProcessor_When_ActorIsBusy()
        throws Exception {

    receiverFlag.set(true);
    when(receiverQueueMock.isEmpty()).thenReturn(false);
    ActorReceiver actorReceiver = new ActorReceiver(childReceiverMock);
    actorReceiver.receive(processorMock);
    verify(receiverQueueMock).add(same(processorMock));
}