Java 监听modbustcp

以下是Java监听ModbusTCP的示例代码：

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

public class ModbusTCPServer {
    public static void main(String[] args) throws Exception {
        ServerSocket server = new ServerSocket(502);
        System.out.println("Modbus TCP server is listening...");

        while (true) {
            Socket socket = server.accept();
            System.out.println("Client connected: " + socket.getRemoteSocketAddress());

            // 处理客户端请求
            Thread thread = new Thread(new ModbusTCPHandler(socket));
            thread.start();
        }
    }
}

class ModbusTCPHandler implements Runnable {
    private Socket socket;

    public ModbusTCPHandler(Socket socket) {
        this.socket = socket;
    }

    public void run() {
        try {
            InputStream in = socket.getInputStream();
            OutputStream out = socket.getOutputStream();

            // 处理Modbus TCP请求
            // ...

            in.close();
            out.close();
            socket.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}

该示例代码创建了一个ServerSocket对象，监听Modbus TCP的默认端口502。当有客户端连接时，会创建一个新的线程来处理客户端请求。在ModbusTCPHandler类的run方法中，可以处理Modbus TCP请求并返回响应。