import net.jini.core.entry.*;
import net.jini.core.lookup.*; 
import net.jini.core.discovery.*; 
import net.jini.discovery.*;
import net.jini.lookup.entry.*; 
import java.rmi.*;

/***************************************************************************

    MyClient -- Uses Discovery to Find the Lookup Server

 ***************************************************************************/

    class MyClient implements DiscoveryListener
      {
      LookupDiscovery discovery;  
      ServiceRegistrar[] registrars;


      MyClient ()
        {
        try 
          {
          discovery = new LookupDiscovery (LookupDiscovery.ALL_GROUPS);
          discovery.addDiscoveryListener (this); 
          System.out.println ("client: searching for lookups...");
          }
        catch (Exception e) 
          {
          System.out.println ("MyClient(): " + e);
          }
        }


      public void discovered (DiscoveryEvent evt)        // DiscoveryListener
        {
        int i;
        LookupLocator ll;
        Entry[] aeAttributes;
        ServiceTemplate template;
        MyServerInterface myServerInterface;


/*      Each cycle of this loop attempts to find MyServerInterface
        in one of the registrars that was passed to this method.
        ==========================================================  */

        registrars = evt.getRegistrars ();
        for (i = 0; i < registrars.length; i++)
          {
          try
            {
            ll = registrars[i].getLocator ();
            System.out.println ("client: got proxy1 to a lookup        [" 
              + ll + "]");

            aeAttributes = new Entry[1];
            aeAttributes[0] = new Name ("MyServer");
            template = new ServiceTemplate (null, null, aeAttributes);

            myServerInterface 
              = (MyServerInterface) registrars[i].lookup (template);
            System.out.println ("client: requested proxy2 by name      [" 
              + ((Name) aeAttributes[0]).name + "]");
            System.out.println ("client: got proxy2                    [" 
              + myServerInterface.getClass().getName() + "]");


/*          If the correct object was returned, call one of its methods 
            then exit the program.
            ===========================================================  */

            if (myServerInterface instanceof MyServerInterface)
              {
              System.out.println ("client: called proxy2.sayHello()      --->"
                + myServerInterface.sayHello () + "<---");
              System.out.println ("*-----------------------------------------"
                + "--------------------------------*\n");
              System.exit (0);
              }
            }
          catch (Exception e)
            {
            System.out.println ("client: exception " + e);
            }
          }
        } 


      public void discarded (DiscoveryEvent evt)         // DiscoveryListener
        {
        int i;

        registrars = evt.getRegistrars ();
        try
          {
          for (i = 0; i < registrars.length; i++)
            {
            System.out.println ("client: discarded lookup              [" 
              + registrars[i].getLocator () + "]");
            }
          }
        catch (Exception e)
          {
          System.out.println ("client: exception " + e);
          }
        }


      public static void main (String[] args)
        {
        MyClient myClient;

        try 
          {
          System.setSecurityManager (new RMISecurityManager ());
          System.out.println ("*-----------------------------------------"
            + "--------------------------------*");

          myClient = new MyClient ();

          Thread.currentThread().join (); 
          myClient.discovery.terminate ();
          } 

        catch (Exception e) 
          {
          System.out.println ("main(): " + e);
          }
        }
      }