对等重置连接:尝试发送对象时出现套接字写入错误

Question

所以当我尝试发送对象时，连接被同级重置:套接字写入错误，我不知道为什么。这只是我大学项目的一小部分，我花了很多时间来尝试它，但我真的没有想法了。如果能得到你的帮助，我将不胜感激。我尝试向客户端发送一条简单的字符串消息，它工作得很好。

服务器代码：

public class Server {
static ServerSocket serverSocket;

public static void main(String args[]) {
    try {
    serverSocket = new ServerSocket(7777);
    Map map = new Map();
    while(true)
    {
        Socket incoming  = serverSocket.accept();
        System.out.println(incoming.toString());
        Runnable r = new ServerConnection(incoming, map);
        Thread t = new Thread(r);
        t.start();
    }       
  }
}

ServerConnection代码：

public class ServerConnection implements Runnable {
private Socket s;
private ObjectOutputStream out;
private Map map;
public ServerConnection(Socket out, Map map){
    this.s = out;
    this.map = map;
    System.out.println(map);
}

public void sendMap(){
    //map.setRotation(rotated);
    try {
        out = new ObjectOutputStream(s.getOutputStream());
        System.out.println(out);
        System.out.println(this.map);
        out.writeObject(this.map);
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}

public void closeSocket(){
    try {
        s.close();
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}

@Override
public void run() {
    //this.connect();
    this.sendMap();
}
}

打印堆栈跟踪提供以下信息：

java.net.SocketException: Connection reset by peer: socket write error
at java.net.SocketOutputStream.socketWrite0(Native Method)
at java.net.SocketOutputStream.socketWrite(Unknown Source)
at java.net.SocketOutputStream.write(Unknown Source)
at java.io.ObjectOutputStream$BlockDataOutputStream.drain(Unknown Source)
at java.io.ObjectOutputStream$BlockDataOutputStream.setBlockDataMode(Unknown Source)`
at java.io.ObjectOutputStream.writeFatalException(Unknown Source)
at java.io.ObjectOutputStream.writeObject(Unknown Source)
at Server.ServerConnection.sendMap(ServerConnection.java:39)
at Server.ServerConnection.run(ServerConnection.java:59)
at java.lang.Thread.run(Unknown Source)

是的，我检查了Map是否不为空，输出是否存在等。我不知道是什么触发了这个问题。

编辑：-对象映射是可序列化的。

客户端控制台输出：

Exception in thread "main" java.lang.NullPointerException
    at Client.ClientConnection.getMap(ClientConnection.java:37)
    at Client.Client.main(Client.java:28)

客户端代码：

public static void main(String[] args) {
    ClientConnection c = new ClientConnection();
    c.connect();
    Map map = c.getMap();
    System.out.println(map);
    c.closeSocket();
}

ClientConnection：- serverString是本地adres "127.0.0.1“

public void connect(){
        try
        {
            Socket s = new Socket(serverString,7777);
        } catch (UnknownHostException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }   
    }

    public Map getMap(){
    Map map;
    try {
        input = new ObjectInputStream(s.getInputStream());
        map = (Map)(input.readObject());
        return map;
    } catch (IOException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    } catch (ClassNotFoundException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }
    return null;
    }
public void closeSocket(){
        try {
            s.close();
        } catch (IOException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }
    }

Answer 1

连接被对方重置意味着对方关闭了连接。既然您展示的是服务器端程序，那么客户端必须是关闭它的那个。检查客户端代码和控制台输出。

编辑:您没有将s赋给类字段，因此当调用getMap时，它始终为null。

更改为以下内容：

Socket s = new Socket(serverString,7777);
this.s = s;