java - java中使用jetty发送json对象

Question

我不明白为什么什么也没有发生。

我正在尝试编写一个java程序，将json对象发送到jetty服务器。服务器已经编写好了(由其他人编写，它是一个项目)，并且仅排除某些 json 对象。但他没有从我的程序中得到任何东西。

public class client {
    final static String HOST = "localhost";
    final static int PORT = 3000;

    public static void main(String[] args)
    {   

        String URIString = "ws://" + HOST + ":" + PORT + "/servlets";
        URI uri = URI.create(URIString);
        WebSocketClient client = new WebSocketClient();

        JSONObject js = new JSONObject();

        js.put("toke","hallo");



        Clientsocket clientsocket = new Clientsocket();
        try {
            client.start();
            Future<Session> fut = client.connect(clientsocket, uri);

            clientsocket.getSession().getRemote().sendString(js.toJSONString());;


        } catch (Exception e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

public class Clientsocket extends WebSocketAdapter {

    //private static final Logger LOG = Log.getLogger(Clientsocket.class);

    @Override
    public void onWebSocketClose(int statusCode,String reason)
    {
        super.onWebSocketClose(statusCode, reason);
        //LOG.info("Websocket Close:{}  - {} ", statusCode,reason);
    }


    @Override
    public void onWebSocketConnect(Session session) 
    {
        super.onWebSocketConnect(session);
        //LOG.info("Websocket Connect: {}", session);

    }


}

启动时出现错误消息:

2018-06-22 14:26:43.789:INFO::main: Logging initialized @257ms to org.eclipse.jetty.util.log.StdErrLog
java.lang.NullPointerException


[both classes: clientsocket, client][1]

Answer 1

我认为您没有等待连接完成。

Future<Session> fut = client.connect(clientsocket, uri);

Session session = fut.get(); // wait for connect to complete (or throw exception)

session.getRemote().sendString(js.toJSONString());