sockjs-client don`t reply the heart-beat from service

[RodJohn]

1. service codes based spring websocket

public class Config implements WebSocketConfigurer {

    @Override
    public void registerWebSocketHandlers(WebSocketHandlerRegistry registry) {
        registry
                .addHandler(myHandler(),"/chatroom")
                .withSockJS()
                .setHeartbeatTime(20000)
                .setDisconnectDelay(10000);
    }
}

2.client based sockjs

var sock = new SockJS('http://localhost:9000/chatroom');

sock.onmessage = function(e) {
    console.log('message', e.data);
}

3.result

here is only the heart beat from service .
sockjs doesn`t reply it 

like this

[brycekahle]

This is expected. See #67 and #297