Socket网络编程（二）

udp协议发送消息案例

1、创建UdpServer（udp服务器端）

package com.cppdy.udp;

import java.net.DatagramPacket;
import java.net.DatagramSocket;

//udp服务器端
public class UdpServer {

    public static void main(String[] args) throws Exception {
        System.out.println("udp服务启动……");
        DatagramSocket ds = new DatagramSocket(8080);

        byte[] buf = new byte[1024];

        DatagramPacket dp = new DatagramPacket(buf, buf.length);

        ds.receive(dp);

        String add = dp.getAddress().toString();

        String data = new String(dp.getData(), 0, dp.getLength());

        System.out.println("服务器接受：从IP" + add + "传输的数据：" + data);
    }

}

2、创建UdpClient（udp客户端）

package com.cppdy.udp;

import java.net.DatagramPacket;
import java.net.DatagramSocket;
import java.net.InetSocketAddress;

//udp客户端
public class UdpClient {

    public static void main(String[] args) throws Exception {

        String msg = "吹泡泡的魚";
        DatagramSocket ds = new DatagramSocket();
        byte[] bytes = msg.getBytes();

        DatagramPacket dp = new DatagramPacket(bytes, bytes.length, new InetSocketAddress("127.0.0.1", 8080));

        ds.send(dp);

        ds.close();

        System.out.println("客户端发送信息完毕……");
    }

}