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;
       }
     }
   }
 }