UDP协议

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

public class UDPSend {

	/**
	 * @param args
	 */
	public static void main(String[] args) throws IOException{
		// TODO Auto-generated method stub
		byte[] data = "你好UDP".getBytes();
         DatagramPacket  dp = new DatagramPacket(data, data.length,InetAddress.getLocalHost(),8000);
//		DatagramPacket  dp = new DatagramPacket
         DatagramSocket ds= new DatagramSocket();
         ds.send(dp);
         ds.close();
	}

}

public class UDPReceive {

	/**
	 * @param args
	 */
	public static void main(String[] args) throws IOException{
		// TODO Auto-generated method stub
         DatagramSocket ds = new DatagramSocket(8000);
         byte[] data = new byte[1024];
         DatagramPacket dp = new DatagramPacket(data, data.length);
         ds.receive(dp);

         String add = dp.getAddress().getHostAddress();
         int port = dp.getPort();
         int len = dp.getLength();
        
         ds.close();
         System.out.println(new String(data,0,len)+"...."+add+":"+port);
	}

}