if (log.isTraceEnabled()) { log.trace(this + " removing the oldest message in memory returns " + result); }
if (trace) { log.trace(this + " removing the oldest message in memory returns " + result); }
   public MessageReference removeFirst()   {      MessageReference result = (MessageReference)messageRefs.removeFirst();      if (log.isTraceEnabled()) { log.trace(this + " removing the oldest message in memory returns " + result); }      return result;   }