code: Object proceedAndSendMessage(InvocationContext ctx, String topic, boolean jsonPayload) throws Exception {
  		MessageToClient messageToClient = new MessageToClient();
  		messageToClient.setId(topic);
  		Object result = ctx.proceed();
  		if(jsonPayload) {
  			if(!String.class.isInstance(result)) {
  				throw new UnsupportedOperationException("Method annotated JsTopic(jsonPayload=true) must return String type and correct Json.");
  			}
  			messageToClient.setJson((String) result);
  		} else {
  			messageToClient.setResponse(result);
  		}
  		wsEvent.fire(messageToClient);
  		return result;
  	}
docs: Proceed the method and send MessageToClient to topic
  @param ctx
  @param topic
  @return
  @throws Exception