import java.net.DatagramPacket;import java.net.DatagramSocket;import java.net.InetAddress;//=================================================// File Name       :	UDPServer_demo//------------------------------------------------------------------------------// Author          :	Common//主类//Function        : 	UDPServer_demopublic class UDPServer_demo {	public static void main(String[] args) throws Exception{		// TODO 自动生成的方法存根		DatagramSocket ds = null;					//声明DatagramSocket对象		DatagramPacket dp = null;					//声明DatagramPacket对象		ds = new DatagramSocket(3000);		String str = "HelloWord";		dp = new DatagramPacket(str.getBytes(),str.length(),InetAddress.getByName("localhost"),9000);		System.out.println("发送信息");		ds.send(dp);		ds.close();	}}

 

import java.net.DatagramPacket;import java.net.DatagramSocket;//=================================================// File Name       :	UDPClient_demo//------------------------------------------------------------------------------// Author          :	Common//主类//Function        : 	UDPClient_demopublic class UDPClient_demo {	public static void main(String[] args) throws Exception{		// TODO 自动生成的方法存根		DatagramSocket ds = null;					//声明DatagramSocket对象		byte[] buf = new byte[1024];			//定义接收数据的字节数据		DatagramPacket dp = null;					//声明DatagramPacket对象		ds = new DatagramSocket(9000);		//此客户端在9000端口监听		dp = new DatagramPacket(buf,1024);			//指定接收数据的长度为1024		System.out.println("等待接收数据");		ds.receive(dp); 				//接收数据		String str = new String(dp.getData(),0,dp.getLength())+" from"		+dp.getAddress().getHostAddress()+" : "+dp.getPort();	//接收数据		System.out.println(str);			//输出数据		ds.close();	}}