qe.agent,
Collections.singleton(qe.agent),
  private void fireAll() {    int n;    List l;    synchronized (heartbeatRequestQueue) {      n = heartbeatRequestQueue.size();      if (n <= 0) {        return;      }      l = new ArrayList(heartbeatRequestQueue);      heartbeatRequestQueue.clear();    }    for (int i = 0; i < n; i++) {      QueueEntry qe = (QueueEntry) l.get(i);      if (qe.action == START) {        HeartbeatRequest hbr =            sensorFactory.newHeartbeatRequest(agentId,                                              qe.agent,                                              qe.hbrTimeout,                                              qe.hbFrequency,                                              qe.hbTimeout,                                              true,                                              qe.pctOutOfSpec);        myUIDs.add(hbr.getUID());        blackboard.publishAdd(hbr);      } else {  // Stop heartbeats        HeartbeatRequest hbr = (HeartbeatRequest)heartbeatRequests.get(qe.agent);        if (hbr != null) {          blackboard.publishRemove(hbr);        }      }    }  }