@PreDestroy
 public void destroy() {
   for (QueueKey key : queryQueues.keySet()) {
     String objectName =
         ObjectNames.builder(QueryQueue.class, key.getQueue().getTemplate())
             .withProperty("expansion", key.getName())
             .build();
     mbeanExporter.unexport(objectName);
   }
 }
 public void setKey(BlockingQueue<Boolean> queue, String newKey) {
   String oldKey = getKey(queue);
   if (oldKey == null) {
     keys.add(new QueueKey(newKey, queue));
   } else if (oldKey.equals(newKey)) {
     for (QueueKey queueKey : keys) {
       if (oldKey.equals(queueKey.key)) {
         queueKey.key = newKey;
         return;
       }
     }
   }
 }