loading a url image to a canvas on a panel?

I'm new a java and am trying to do a slideshow where i can view 20 predetermind slides names pic01.jpg to pic20.jpg from a url passed to the class file by the calling html file. Can anyone look over the code i have so far and tell me if im going in the right direction? I cant seem to display the first slide in the canvas i added to my panel. my buttons show up but not the image. How do i pass the url to the slideshow.class file and display the first pic01.jpg file. Also how do I do an array of pictures i can scroll through and how do i update the slide canvas?

Many questions, I Know, I'll offer 200 points up to anyone that can help me. See attached code below..


// not sure if im importing all i need or too much
import java.awt.*;
import java.awt.image.*;
import java.awt.Graphics;
import java.net.*;
import java.awt.event.*;
import java.applet.*;
import corejava.*;

public class SlideShow extends Applet implements ActionListener
{   public void init()
    {      // use default panel layout));
      // add five buttons
      Panel p = new Panel();
      Button firstButton = new Button("<<");
      p.add(firstButton);
      firstButton.addActionListener(this);

      Button backButton = new Button("<");
      p.add(backButton);
      backButton.addActionListener(this);

      Button nextButton = new Button(">");
      p.add(nextButton);
      nextButton.addActionListener(this);

      Button lastButton = new Button(">>");
      p.add(lastButton);
      lastButton.addActionListener(this);

      Button closeButton = new Button("Close");
      p.add(closeButton);
      closeButton.addActionListener(this);

      // add canvas for displaying slide
      add(p,"South");
      slide = new SlideCanvas();
      add(slide,"North");
    }
    public void actionPerformed(ActionEvent evt)
    {      String arg = evt.getActionCommand();
      if (arg.equals("<<")) slide.first();
      else if (arg.equals("<")) slide.back();
      else if (arg.equals(">")) slide.next();
      else if (arg.equals(">>")) slide.last();
      else if (arg.equals("Close")) System.exit(0);
    }  
    private SlideCanvas slide;
}

class SlideCanvas extends Canvas
{   public void paint(Graphics g)       
    {      // show first slide in canvas

      String s = "pic01.jpg";
        Image image = Toolkit.getDefaultToolkit().getImage(s);      
        g.drawImage(image,0,0,this);
    }

    public void first()
    {      // go to first slide      
      repaint();
    }

    public void back()
    {   // back one slide      
      repaint();
    }

    public void next()
    {      // forward one slide
      repaint();
    }

    public void last()
    {      // go to last slide
      repaint();
    }
    private int counter = 0;
}