【网络原理】使用Java基于TCP搭建简单客户端与服务器通信

以下是一个简单的Java TCP Socket客户端和服务器端的例子。服务器端接收客户端发送的消息并将其打印出来。

服务器端 (Server.java):

import java.io.*;
import java.net.*;
 
public class Server {
    public static void main(String[] args) throws IOException {
        ServerSocket serverSocket = null;
        try {
            serverSocket = new ServerSocket(1234); // 监听1234端口
            Socket socket = serverSocket.accept(); // 等待客户端连接
            System.out.println("Client connected!");
 
            BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
            String str = in.readLine();
            System.out.println("Client says: " + str);
 
            PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
            out.println("Server received the message.");
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (serverSocket != null) {
                serverSocket.close();
            }
        }
    }
}

客户端 (Client.java):

import java.io.*;
import java.net.*;
 
public class Client {
    public static void main(String[] args) throws IOException {
        Socket socket = null;
        try {
            socket = new Socket("localhost", 1234); // 连接到本地主机的1234端口
            PrintWriter out = new PrintWriter(socket.getOutputStream(), true);
            BufferedReader in = new BufferedReader(new InputStreamReader(socket.getInputStream()));
 
            out.println("Hello from Client"); // 发送消息
            System.out.println("Client says: Hello from Client");
 
            String response = in.readLine(); // 接收响应
            System.out.println("Server says: " + response);
        } catch (UnknownHostException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            if (socket != null) {
                socket.close();
            }
        }
    }
}

在运行这些代码之前，请确保没有其他服务占用1234端口。运行服务器端 (Server.java) 将会创建一个监听1234端口的服务器，然后运行客户端 (Client.java) 将会连接到服务器并发送消息。服务器接收到消息后，将响应客户端并关闭连接。