@Override
    public void sendToGroups(final Map<String, RequestCommand> groupObjects, final MultiGroupCallBackListener listener,
            final long timeout, final TimeUnit timeUnit, final Object... args) throws NotifyRemotingException {
        this.remotingClient.sendToGroups(groupObjects, listener, timeout, timeUnit, args);
    }
Whether to enable loopback connection for metaq client, default is false.
metamorphosis-client/src/main/java/com/taobao/metamorphosis/client/RemotingClientWrapper.java