public void OnMessage(Msg msg)
 {
     if (msg is MQueryExecute)
     {
         _enclosing.processingMessage = true;
         barrier.Add(new object());
         Runtime4.Sleep(500);
         _enclosing.processingMessage = false;
     }
     else
     {
         if (msg is MIsAlive)
         {
             Assert.IsFalse(_enclosing.processingMessage);
         }
     }
 }
 public virtual void Add(object obj)
 {
     queue.Add(obj);
 }