java - 如何发现客户端android套接字断开连接？

Question

我在服务器端遇到问题，当我故意拔掉android wifi时，服务器无法检测到通信已结束。

关闭应用程序服务器时发现。

/**
 * Method Responsible for receiving last message from client socket.
 *
 * @return
 * @throws java.io.IOException
 */
public String receive() throws IOException {
    //receiver is a Scanner -> receiver = new Scanner(socket.getInputStream());
    while (receiver.hasNextLine()) {
     return receiver.nextLine();
     }
     return null;
}

@Override
public void run() {
    //loop waiting for the client message
    while (true) {
        String response;
        //receive message
        try {
            response = receive();
            //if the message come null means that the client disconnected
            if (response == null) {
                break;
            }
        } catch (Exception e) {
            break;
        }
        //mount message.
        Message msg;
        try {
            msg = new Gson().fromJson(response, Message.class);
        } catch (Exception e) {
            continue;
        }
        //manage message in new thread
        new Thread(new Runnable() {
            @Override
            public void run() {
                manageMessage(msg);
            }
        }).start();
    }
    close();
}

当客户端断开连接时，receive()方法总是返回null，但是当我关闭wifi android时，该方法被搁置。

Answer 1

在套接字上设置合适长度的读取超时，并捕获SocketTimeoutException。

如果您不打算迭代，为什么要使用 while 循环？