【UDP 发送接收数据】

package com.yjf.esupplier.common.test;

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

/**
 * @author shusheng
 * @description UDP 发送接收数据
 * @Email [email protected]
 * @date 2019/1/6 0:21
 */
public class SendDemo {

    public static void main(String[] args) throws Exception {
        DatagramSocket socket = new DatagramSocket();
        String str = "i love you";
        // 把数据进行封装到数据报包中
        DatagramPacket packet = new DatagramPacket(str.getBytes(),
                str.length(), InetAddress.getByName("localhost"), 6666);
        socket.send(packet);// 发送

        byte[] buff = new byte[100];
        DatagramPacket packet2 = new DatagramPacket(buff, 100);
        socket.receive(packet2);
        System.out.println(new String(buff, 0, packet2.getLength()));
        socket.close();
    }

}

package com.yjf.esupplier.common.test;

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

/**
 * @author shusheng
 * @description UDP 发送接收数据
 * @Email [email protected]
 * @date 2019/1/7 23:24
 */
public class ReceiveDemo {

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

        // 先接收数据
        DatagramSocket socket = new DatagramSocket(6666);
        byte[] buff = new byte[100];
        DatagramPacket packet = new DatagramPacket(buff, buff.length);
        socket.receive(packet);// 接受传来的数据包
        System.out.println(new String(buff, 0, packet.getLength()));

        // 发送数据
        String str = "me too";
        DatagramPacket packet2 = new DatagramPacket(str.getBytes(),
                str.length(), packet.getAddress(), packet.getPort());
        socket.send(packet2);
        socket.close();
    }

}