@Override
  public boolean containsMessage(String queueName, String messageId) {
    if (!queues.containsKey(queueName)) {
      queues.put(queueName, new ConcurrentLinkedDeque<>());
    }
    return queues.get(queueName).contains(messageId);
  }
@Test
  public void testContainsMessage() {
    String queueName = "test-queue";
    String id = "abcd-1234-defg-5678";
    assertFalse(queueDao.containsMessage(queueName, id));
    assertEquals(1, internalQueue.size());
    assertTrue(internalQueue.get(queueName).isEmpty());

    assertTrue(queueDao.pushIfNotExists(queueName, id, 123));
    assertTrue(queueDao.containsMessage(queueName, id));
    assertEquals(1, internalQueue.size());
    assertEquals(1, internalQueue.get(queueName).size());
    assertEquals(id, internalQueue.get(queueName).peek());
  }