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java如何开tcp

2026-03-23 19:56:03Java

TCP 通信实现方法

Java 提供了 java.net.Socket 和 java.net.ServerSocket 类用于 TCP 通信。以下是客户端和服务端的实现示例。

服务端代码

服务端通过 ServerSocket 监听指定端口，接受客户端连接后通过 Socket 进行通信。

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

public class TCPServer {
    public static void main(String[] args) throws IOException {
        int port = 8080;
        ServerSocket serverSocket = new ServerSocket(port);
        System.out.println("Server started on port " + port);

        Socket clientSocket = serverSocket.accept();
        System.out.println("Client connected: " + clientSocket.getInetAddress());

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

        String message = in.readLine();
        System.out.println("Received: " + message);

        out.println("Server response: " + message);

        in.close();
        out.close();
        clientSocket.close();
        serverSocket.close();
    }
}

客户端代码

客户端通过 Socket 连接到服务端，发送数据并接收响应。

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

public class TCPClient {
    public static void main(String[] args) throws IOException {
        String host = "localhost";
        int port = 8080;

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

        out.println("Hello from client");

        String response = in.readLine();
        System.out.println("Server response: " + response);

        out.close();
        in.close();
        socket.close();
    }
}

多线程服务端

为支持多客户端连接，服务端可使用多线程处理每个客户端请求。

java如何开tcp

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

public class MultiThreadedServer {
    public static void main(String[] args) throws IOException {
        int port = 8080;
        ServerSocket serverSocket = new ServerSocket(port);
        System.out.println("Server started on port " + port);

        while (true) {
            Socket clientSocket = serverSocket.accept();
            new Thread(new ClientHandler(clientSocket)).start();
        }
    }

    static class ClientHandler implements Runnable {
        private final Socket clientSocket;

        ClientHandler(Socket socket) {
            this.clientSocket = socket;
        }

        public void run() {
            try {
                BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));
                PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);

                String message = in.readLine();
                System.out.println("Received from " + clientSocket.getInetAddress() + ": " + message);

                out.println("Server response: " + message);

                in.close();
                out.close();
                clientSocket.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }
}