Java Socket UDP编程

 package com;

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

 /**
  * UDP Client
  *
  * Created by Administrator on 2018/5/3.
  */
 public class Client {

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

         /**
          * send message
          */
         InetAddress inetAddress = InetAddress.getByName("localhost");
         byte[] data = "name:tom, pwd:123".getBytes();
         DatagramPacket datagramPacket = new DatagramPacket(data, data.length, inetAddress, 8800);
         DatagramSocket datagramSocket = new DatagramSocket();
         datagramSocket.send(datagramPacket);

         /**
          * receive message
          */
         byte[] data2 = new byte[1024];
         DatagramPacket datagramPacket1 = new DatagramPacket(data2, data2.length);
         datagramSocket.receive(datagramPacket1);
         String info = new String(data2, 0, data2.length);
         System.out.println("I am Client, Server say:" + info);

         /**
          * close resource
          */
         datagramSocket.close();
     }
 }

 package com;

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

 /**
  * UDP Server
  *
  * Created by Administrator on 2018/5/3.
  */
 public class Server {

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

         DatagramSocket datagramSocket = new DatagramSocket(8800);

         /**
          * receive message
          */
         byte[] bytes = new byte[1024];
         DatagramPacket datagramPacket = new DatagramPacket(bytes, bytes.length);
         datagramSocket.receive(datagramPacket);
         String info = new String(bytes, 0, datagramPacket.getLength());
         System.out.println("I am Server, Client say: " + info);

         /**
          * send message
          */
         InetAddress inetAddress = datagramPacket.getAddress();
         int port = datagramPacket.getPort();
         byte[] data = "welcome!".getBytes();
         DatagramPacket datagramPacket1 = new DatagramPacket(data, data.length, inetAddress, port);
         datagramSocket.send(datagramPacket1);

         /**
          * close resource
          */
         datagramSocket.close();
     }
 }