udpscan.java

这个程序可以扫描出来本机IP地址的版本号和类别

import java.net.*;
	
	public class UDPScan
	{
		  public static void main(String args[])
		  {
			for (int port=1024;port<=65535;port++) {
			   try {
			      DatagramSocket server=new DatagramSocket(port);
			      server.close();
		   }
			   catch(SocketException e) {
				 System.out.println("there is a server in port "+port+".");
			   }
	     }
		 }
	}