DatagramSocket例子「建议收藏」

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

public class Sender {

    public static void main(String[] args) throws Exception {
        DatagramSocket sender = new DatagramSocket();// 1、创建DatagramSocket(可以设置本地端口,或由系统分配)
        String msg = "你好!";
        byte[] buf = msg.getBytes();
        DatagramPacket packet = new DatagramPacket(buf, buf.length,
                InetAddress.getByName("127.0.0.1"), 10000);// 2、创建用于发送的DatagramPacket(主要设置发送的数据、远程地址和端口等信息)
        System.out.println("sender:发送信息----" + msg);
        sender.send(packet);// 3、通过DatagramSocket发送DatagramPacket
        System.out.println("sender:已经发送了信息");
        sender.close();// 4、关闭DatagramSocket
    }

}

 1 import java.net.DatagramPacket;
 2 import java.net.DatagramSocket;
 3 
 4 public class Receiver {
 5 
 6     public static void main(String[] args) throws Exception {
 7         DatagramSocket receiver = new DatagramSocket(10000);// 1、创建DatagramSocket(主要设置本地地址和端口等信息)
 8         byte[] buf = new byte[1024];
 9         DatagramPacket packet = new DatagramPacket(buf, buf.length);// 2、创建用于接受的DatagramPacket(不需要设置地址和端口)
10         System.out.println("receiver:等待接收");
11         receiver.receive(packet);// 3、通过DatagramSocket接受发送方信息,填充DatagramPacket
12         String msg = new String(packet.getData(), 0, packet.getLength());// 4、读取DatagramPacket的数据
13         System.out.println("receiver:得到的信息是：-----" + msg);
14         receiver.close();// 5、关闭DatagramSocket
15     }
16 
17 }