在Java中使用Jetty发送JSON对象

Question

我不知道为什么什么也没发生。我正在尝试编写一个将json对象发送到码头服务器的java程序。该服务器已经被写入（由其他人，它是一个项目），并且只有某些json对象除外。但是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);    }}启动时出现错误信息：2018-06-22 14:26:43.789:INFO::main: Logging initialized @257ms to org.eclipse.jetty.util.log.StdErrLogjava.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());