code: @Override
    public void queryFail(HeadersAmp headers, long qid, Throwable exn)
    {
      try (OutboxAmp outbox = OutboxAmp.currentOrCreate(_serviceRef.services())) {
        _serviceRef.offer(new QueryErrorMessage(outbox,
                                                _serviceRef, 
                                                headers,
                                                _serviceRef.stub(),
                                                qid, 
                                                exn));
      }
    }
docs: /* (non-Javadoc)
  @see com.caucho.ramp.remote.GatewayReply#queryError(com.caucho.ramp.spi.RampHeaders, long, java.lang.Throwable)