Exception while connecting to url-java.net.UnknownHostException

import java.io.IOException;
import java.io.InputStreamReader;
import java.net.URL;
import java.net.URLConnection;
public class Trial {
	 public static void main(String[] args)
     {
          try
                 {
                   URL PageUrl;
                   URLConnection GetConn = null;
                   GetConn = null;
                   
                    PageUrl = new URL("http://www.google.com");
                    GetConn = PageUrl.openConnection();
                    //establish connection:
                   //GetConn.connect();
                   //save privacy policy source file into text file
                    System.out.println(GetConn.getURL());
                    System.out.println("----");
                    System.out.println(GetConn.getInputStream());
                    System.out.println("----***");
                   InputStreamReader ReadIn = new InputStreamReader(GetConn.getInputStream());
                
                 }catch(IOException io)
                 {
                     System.out.println(io);
                }
     }
}