tp1.java

exemple for using java chat client + server

/*
 * tp&.java
 *
 * Created on 11 octobre 2008, 12:25
 *
 * To change this template, choose Tools | Template Manager
 * and open the template in the editor.
 */

package reseaux;

/**
 *
 * @author Mustapha
 */
import java.net.*;

public class tp1 {
    
    /** Creates a new instance of tp1 */
    public tp1() {
    }
    
    /**
     * @param args the command line arguments
     */
    public static void main(String[] args)  {
        // TODO code application logic here
       // InetAddress  adress = InetAddress.getByName("www.google.com");
     try{
          //InetAddress  adress = InetAddress.getByName("www.google.com");
        // InetAddress [] adr = InetAddress.getAllByName("www.google.com");
         InetAddress  local = InetAddress.getLocalHost();
          InetAddress a = InetAddress.getLocalHost(); ;
          InetAddress aa = InetAddress.getLocalHost();;
          if(a.equals(aa))
          {
              System.out.println("ok");
          }
          else
          {
              System.out.println("non");
          } 
                 int b = getversion(local);
                 char c = getclass(local);
         System.out.println(local.getHostAddress()+" IPv "+b+" et de classe "+c);
         }
        catch(UnknownHostException e)
        {
            System.out.println("erreur");
        }
        
            }
    public static int getversion(InetAddress a )
    {
        byte [] adres = a.getAddress();
        if(adres.length==4)
            return 4;
        else if(adres.length==6) return 6;
        else return -1;
            
     }
       
            public static char getclass(InetAddress a )
    {
        byte [] adres = a.getAddress();
       if(adres.length==4)
       {
            int b1 = adres[0];
            if((b1&0x80)==0) return 'A';
            else 
            {
                if ((b1&0xc0)==0x80) return 'B';
               else 
               {
                    if ((b1&0xe0)==0xc0) return 'C';
                    else 
                    {
                        if ((b1&0xf0)==0xf0) return 'D';
                        else 
                        {
                            if ((b1&0xf8)==0xf0) return 'E';
                             else return 'X';
                        }
                    }
               }
            }
            
    }
       else return 'X';
            }
    }