Java网络编程二 UDP通信-优快云博客

本文链接：https://blog.youkuaiyun.com/iteye_8851/article/details/81937172

本文提供了一个简单的UDP通信实例，包括服务端与客户端的Java代码实现。服务端监听1000端口接收客户端发送的数据包，并打印客户端的IP地址、端口号及发送的内容。客户端则构造包含整数与字符串信息的数据包并发送到指定的服务端。

摘要生成于 C知道，由 DeepSeek-R1 满血版支持，前往体验 >

1. 服务端

import java.io.BufferedReader;
import java.io.ByteArrayInputStream;
import java.io.DataInputStream;
import java.io.InputStreamReader;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.SocketException;

public class UdpServer {

    public static void main(String[] args) {
        try {
            DatagramSocket ds = new DatagramSocket(1000);
            byte[] buf = new byte[1024];
            while(true){
                DatagramPacket dp = new DatagramPacket(buf, buf.length);
                ds.receive(dp);
                System.out.println("client ----> IP: " + dp.getAddress().getHostAddress() + ", port: " + dp.getPort());
                DataInputStream dis = new DataInputStream(new ByteArrayInputStream(dp.getData()));
                System.out.println(dis.readInt());
                BufferedReader d = new BufferedReader(new InputStreamReader(dis));
                System.out.println(new String(d.readLine()));
            }
        } catch (SocketException e) {
            e.printStackTrace();
        } catch (Exception e) {
            e.printStackTrace();
        }

    }

}

2. 客户端

import java.io.ByteArrayOutputStream;
import java.io.DataOutputStream;
import java.io.IOException;
import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;
import java.net.SocketException;

public class UdpClient {

    public static void main(String[] args) {
        try {
            DatagramSocket ds = new DatagramSocket();

            ByteArrayOutputStream baos = new ByteArrayOutputStream();
            DataOutputStream dos = new DataOutputStream(baos);
            dos.writeInt(200);
            dos.write("你好".getBytes());
            System.out.println("字节数: " + dos.size());
            byte[] buf = baos.toByteArray();
            DatagramPacket dp = new DatagramPacket(buf, buf.length, new InetSocketAddress("127.0.0.1", 1000));

            ds.send(dp);
            ds.close();
        } catch (SocketException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }

    }

}