写一个socket简易聊天程序代码，用java语言

以下是一个简单的 Java Socket 聊天程序的示例代码：

Server.java

import java.io.*;
import java.net.*;

public class Server {
    public static void main(String[] args) {
        try {
            ServerSocket serverSocket = new ServerSocket(8000);
            System.out.println("Server started");

            Socket socket = serverSocket.accept();
            System.out.println("Client connected");

            BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            PrintWriter out = new PrintWriter(socket.getOutputStream(), true);

            while (true) {
                String message = in.readLine();
                if (message == null) {
                    break;
                }
                System.out.println("Client: " + message);
                out.println("Server: " + message);
            }

            socket.close();
            System.out.println("Client disconnected");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Client.java

import java.io.*;
import java.net.*;

public class Client {
    public static void main(String[] args) {
        try {
            Socket socket = new Socket("localhost", 8000);
            System.out.println("Connected to server");

            BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            PrintWriter out = new PrintWriter(socket.getOutputStream(), true);

            BufferedReader console = new BufferedReader(new InputStreamReader(System.in));

            while (true) {
                String message = console.readLine();
                if (message == null) {
                    break;
                }
                out.println(message);
                System.out.println("Server: " + in.readLine());
            }

            socket.close();
            System.out.println("Disconnected from server");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

这个聊天程序使用了 Java 的 Socket API，Server 程序监听端口 8000，等待客户端连接；Client 程序向服务器的 8000 端口发起连接请求。一旦连接建立，就可以在控制台输入消息并发送给对方。程序会一直运行直到某方断开连接。