Dice program demonstrating the use of graphic powered buttons.

Dice.java

//Imports
import java.awt.*;
import javax.swing.*;
import java.awt.event.*;
import java.util.*;

public class Dice extends JFrame{
	//Nested die class.
	private class Die {
		private int val;
		
		public Die(){
			roll();
		}
		
		public void roll(){
			Random rand = new Random();
			val = rand.nextInt(6) + 1;
		}
		
		public String getVal(){
			return val + "";
		}
	}
		
	//If the button is hovered.
	private boolean hover = false;
	
	//Dice
	private Die die1 = new Die();
	private Die die2 = new Die();
	
	public Dice(){
		//Initial shat.
		super("Dice");
		setSize(300, 130);
		
		//Create a new MouseAdapter
		MouseAdapter listen = new MouseAdapter(){
			public void mouseMoved(MouseEvent e){
				/*
				 * Only repaint when necessary to prevent excessive repaints that look really bad.
				 */
				
				//If hover was previously false.
				if(!hover){
					//Check to see if the mouse is now inside the button.
					if(e.getX() >= 50 && e.getX() <= 125 && e.getY() >= 50 && e.getY() <= 95){
						//Set hovered to true, set the cursor to the hand, and repaint.
						hover = true;
						setCursor(Cursor.getPredefinedCursor(Cursor.HAND_CURSOR));
						
						repaint();
					}
				}
				else{
					//If the mouse is now outside the button.
					if(!(e.getX() >= 50 && e.getX() <= 125 && e.getY() >= 50 && e.getY() <= 95)){
						//Set hovered to false, set the cursor to the default one, and repaint.
						hover = false;
						setCursor(Cursor.getPredefinedCursor(Cursor.DEFAULT_CURSOR));
						
						repaint();
					}
				}
			};
			
			public void mouseClicked(MouseEvent e){
				if(hover){
					roll();
					repaint();
				}
		    }
		};
		
		//Make sure we add the listener.
		addMouseMotionListener(listen);
		addMouseListener(listen);
	}
	
	public void paint(Graphics g){
		//Make sure we're using Graphics2D
		Graphics2D g2d = (Graphics2D) g;
		
		//Anti alias graphics.
		g2d.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON);
		
		//Set the font.
		g2d.setFont(new Font("Arial", Font.PLAIN, 28));
		
		//Paint the background.
		g2d.setColor(Color.white);
		g2d.fillRect(0, 0, getWidth(), getHeight());
		
		//Paint the button.
		//Determine what color the button should be based on whether it is hovered or not.
		g2d.setColor(hover ? Color.gray : Color.black);
		g2d.fillRect(50, 50, 75, 45);
		
		//Paint Dice
		g2d.setColor(Color.black);
		g2d.drawRect(135, 50, 45, 45);
		g2d.drawRect(190, 50, 45, 45);
				
		//Text will be painted later as Trebuchet MS needs to be loaded.
		g2d.setColor(Color.white);
		g2d.drawString("Roll", 65, 80);
		
		//Paint die values.
		g2d.setColor(Color.black);
		g2d.drawString(die1.getVal(), 150, 82);
		g2d.drawString(die2.getVal(), 205, 82);
	}
	
	public static void main(String[] args){
		//Instantiate a new pair of Dice and set them to visible.
		new Dice().setVisible(true);
	}
	
	public void roll(){
		die1.roll();
		die2.roll();
	}
}