如何发现客户端android socket断开连接？

Question

我有一个服务器端的问题，当我特意拔掉android wifi服务器无法检测到通信结束。

当关闭应用程序服务器时发现。当客户端断开连接，但是当我关掉了wifi的机器人，该方法被搁置

/** 
* 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(); 
} 

的方法总是返回null。

Answer 1

在套接字上设置适当长度的读取超时，并捕获SocketTimeoutException。

为什么while循环，如果你不打算迭代？