java socket如何实现多线程通信

在Java中，可以通过多线程来实现Socket通信。下面是一个简单的示例代码，演示了如何使用多线程实现Socket通信：

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 MultiThreadedServer {    public static void main(String[] args) {        ServerSocket serverSocket = null;        try {            serverSocket = new ServerSocket(12345);            System.out.println("Server started. Listening for connections on port 12345...");            while (true) {                Socket clientSocket = serverSocket.accept();                System.out.println("Connection received from " + clientSocket.getInetAddress().getHostAddress());                ClientHandler clientHandler = new ClientHandler(clientSocket);                Thread clientThread = new Thread(clientHandler);                clientThread.start();            }        } catch (IOException e) {            e.printStackTrace();        } finally {            if (serverSocket != null) {                try {                    serverSocket.close();                } catch (IOException e) {                    e.printStackTrace();                }            }        }    }    static class ClientHandler implements Runnable {        private Socket clientSocket;        public ClientHandler(Socket clientSocket) {            this.clientSocket = clientSocket;        }        @Override        public void run() {            try (                    BufferedReader in = new BufferedReader(new InputStreamReader(clientSocket.getInputStream()));                    PrintWriter out = new PrintWriter(clientSocket.getOutputStream(), true);            ) {                String inputLine;                while ((inputLine = in.readLine()) != null) {                    System.out.println("Received from client: " + inputLine);                    out.println("Server received: " + inputLine);                }            } catch (IOException e) {                e.printStackTrace();            }        }    }}

在这个示例中，ServerSocket在端口12345上监听客户端连接。一旦有连接建立，就会创建一个新的ClientHandler线程来处理该连接。ClientHandler类实现了Runnable接口，用于处理客户端的输入和输出。

在ClientHandler线程中，我们创建了一个BufferedReader来读取客户端发送的消息，并通过PrintWriter来向客户端发送消息。循环读取客户端发送的消息，直到客户端关闭连接。

这样，通过多线程的方式，我们可以实现Socket通信，并同时处理多个客户端的连接。