Javaで実装されたメッセージリマインダーツール

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.ServerSocket;
import java.net.Socket;

public class MessageNotifier {
    private static final int PORT = 8888;

    public static void main(String[] args) {
        ServerSocket serverSocket = null;
        Socket clientSocket = null;

        try {
            // 创建服务器套接字并开始监听端口
            serverSocket = new ServerSocket(PORT);
            System.out.println("服务器已开启，等待连接...");

            // 接受客户端连接请求
            clientSocket = serverSocket.accept();
            System.out.println("客户端连接成功！");

            // 获取输入输出流
            BufferedReader in = new BufferedReader(
                    new InputStreamReader(clientSocket.getInputStream()));
            PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);

            // 接收消息
            String message = in.readLine();
            System.out.println("收到消息：" + message);

            // 发送消息
            out.println("消息已收到！");

            // 关闭连接
            clientSocket.close();
            serverSocket.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.PrintWriter;
import java.net.Socket;

public class MessageClient {
    private static final String HOST = "localhost";
    private static final int PORT = 8888;

    public static void main(String[] args) {
        Socket socket = null;
        PrintWriter out = null;
        BufferedReader in = null;

        try {
            // 创建客户端套接字并连接服务器
            socket = new Socket(HOST, PORT);

            // 获取输入输出流
            out = new PrintWriter(socket.getOutputStream(), true);
            in = new BufferedReader(new InputStreamReader(socket.getInputStream()));

            // 发送消息
            out.println("Hello, Server!");

            // 接收消息
            String message = in.readLine();
            System.out.println("收到回复：" + message);

            // 关闭连接
            out.close();
            in.close();
            socket.close();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}