Java Grafikbutton auf Hintergrundbild

import java.awt.Dimension;
import java.awt.Graphics;
import java.awt.Rectangle;

import javax.swing.Box;
import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JPanel;
  
  public class BackgroundImageExample extends JFrame {
  
  	/**
	 * 
	 */
	private static final long serialVersionUID = 1L;

	public BackgroundImageExample() {
  		super("Hot Labyrinth");
  		setDefaultCloseOperation(EXIT_ON_CLOSE);
   		Box box;
  		box = Box.createVerticalBox();
  		
  		box.add(new BackgroundPanel(new ImageIcon("C:/Users/ro/Desktop/bg.jpg")));
  		
  		
  		JButton Bild = new JButton();
  		ImageIcon iI=new ImageIcon("C:/Users/ro/Desktop/startbutton.jpg");
  		Bild.setBounds(new Rectangle(0, 0, iI.getIconWidth(), iI.getIconHeight()));
  		Bild.setIcon(iI);
  		
  		box.add(Bild);
  		
  		
  		add(box);
  		
  		pack();
  		setVisible(true);
  	}
  
  	/**
  	 * @param args
  	 */
  	public static void main(String[] args) {
  		new BackgroundImageExample();
  	}
  
  	class BackgroundPanel extends JPanel {
  		/**
		 * 
		 */
		private static final long serialVersionUID = 1L;
		ImageIcon icon;
  
  		public BackgroundPanel(ImageIcon icon) {
  			this.icon = icon;
  		}
  
  		protected void paintComponent(Graphics g) {
  			super.paintComponent(g);
  			if (this.icon != null) {
 				g.drawImage(icon.getImage(), 0, 0, this);
  			}
  		}
  
  		public Dimension getPreferredSize() {
  			if (icon != null) {
 			    return new Dimension(icon.getIconWidth(), icon.getIconHeight());
  			} else {
 				return super.getPreferredSize();
  			}
  		}
  	}
  }