if (log.isTraceEnabled()) { log.trace("handle(" + r + ")"); }
   public Delivery handle(Routable r)   {      // Mark the message as being received from a remote endpoint      r.putHeader(Routable.REMOTE_ROUTABLE, Routable.REMOTE_ROUTABLE);      Delivery d = receiver.handle(null, r, null);      // we only accept synchronous deliveries at this point      if (d != null && !d.isDone())      {         throw new IllegalStateException("Cannot handle asynchronous deliveries at this end");      }      return d;   }