helloapplet.java

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/*
 * Copyright 1999 by dreamBean Software,
 * All rights reserved.
 */
package masteringrmi.helloapplet.client;

import java.applet.Applet;
import java.awt.Label;
import java.rmi.RemoteException;

import javax.naming.InitialContext;
import javax.naming.NamingException;

import masteringrmi.helloapplet.interfaces.HelloWorld;

/**
 *   This is an applet that will talk to the remote object.
 *   After lookup of remote object, it will query it for a
 *   greeting, which will be shown in the GUI.
 *      
 *   @see HelloWorld
 *   @author Rickard 謆erg ([e-mail])
 */
public class HelloApplet
   extends Applet
{
   // Attributes ----------------------------------------------------
   /**
    *   The response will shown in this label
    */
   Label response = new Label();
   // Constructors --------------------------------------------------

   /*#HelloWorld Uses;*/

   /**
    *   Initialize GUI
    *
    */
   public HelloApplet()
   {
      // Setup GUI
      add("Center",response);
   }

   // Public --------------------------------------------------------
   
   // Applet overrides ----------------------------------------------
   /**
    *   Lookup and call the remote object.
    */
   public void init()
   {
      try
      {
         // Create URL to remote server
         String url = "rmi://"+getCodeBase().getHost()+"/"+HelloWorld.NAME;
            
         // Locate remote object
         HelloWorld server = (HelloWorld)new InitialContext().lookup(url);
         
         // Call server and show response
         response.setText(server.helloWorld("World"));
      } catch (NamingException e)
      {
         response.setText("The server could not be found");
         e.printStackTrace(System.err);
      } catch (RemoteException e)
      {
         response.setText("The object could not be called");
         e.printStackTrace(System.err);
      } catch (Exception e)
      {
         response.setText(e.getMessage());
         e.printStackTrace(System.err);
      }
   }
}