Exception in thread "main" java.net.SocketException: Connection reset， dis.readUTF()方法报错删掉后可以运行

Question

package com.example.test3;

import java.io.*;
import java.net.Socket;
import java.util.Scanner;

public class TestClient {//客户端
    public static void main(String[] args) throws IOException {
        System.out.println("客户端启动");
        //1.创建Socket，用来发送请求的，指定服务器端的IP和端口号
        Socket s = new Socket("localhost",8888);
        //录入账号密码
        Scanner sc = new Scanner(System.in);
        System.out.print("请录入账号：");
        String username = sc.next();
        System.out.print("请输入密码：");
        String password = sc.next();
        //将账号密码封装成为User对象
        User user = new User(username, password);
        //2.对于客户端来说，我们直观的感受是用流来发送数据
        OutputStream os = s.getOutputStream();
        ObjectOutputStream oos = new ObjectOutputStream(os);
        oos.writeObject(user);
        //接收服务器端数据
        s.shutdownOutput();
        InputStream is = s.getInputStream();
        DataInputStream dis = new DataInputStream(is);
        System.out.println("登录结果："+dis.readUTF());
        System.out.println("222");
        //关闭流，关闭套接字资源
        dis.close();
        is.close();
        oos.close();
        os.close();
        s.close();
    }
}

把上面那个dis.readUTF()删掉后可以运行，调用其他方法也可以输出222，read方法就报错

package com.example.test3;

import java.io.*;
import java.net.ServerSocket;
import java.net.Socket;

public class TestServer {//服务器端

    public static void main(String[] args) throws IOException, ClassNotFoundException {
        System.out.println("服务器端启动");
        //1.创建一个套接字，指定本侧的端口号
        ServerSocket ss = new ServerSocket(8888);
        //2.通过ServerSocket的accept方法获取服务器端的套接字
        Socket s = ss.accept();
        //3.对于服务器端来说，我们用流接收数据
        InputStream is = s.getInputStream();
        ObjectInputStream ois = new ObjectInputStream(is);
        User user = (User)(ois.readObject());
        //进行校验
        String str = null;
        if (user.getUsername().equals("root")&&user.getPassword().equals("123123")){
            str = "登录成功";
        }else {
            str = "登录失败";
        }
        //服务器对客户端的响应
        s.shutdownInput();
        OutputStream os = s.getOutputStream();
        DataOutputStream dos = new DataOutputStream(os);
        dos.writeUTF(str);
        //4.关闭流，关闭网络资源
        dos.close();
        os.close();
        ois.close();
        is.close();
        s.close();
        ss.close();
    }
}

Answer 1

把要发送的数据封装到JavaBean里面，直接发送JavaBean，接收也一样，转换为JavaBean，JavaBean要实现系列化接口。