How can I successfully extend Graphics in Java

import java.awt.*;
import java.awt.image.*;
import java.text.AttributedCharacterIterator;
import javax.swing.*;

public class GraphicsTest {

public static void main(String[] args) {
	new GraphicsTest();
}

public GraphicsTest () {
	JFrame frame = new JFrame();
	frame.getContentPane().add(new MyPanel());
	frame.setSize(500,500);
	frame.setVisible(true);
	try {
		Thread.sleep(2000);
	} catch (InterruptedException e) {}
	System.out.println("Using my graphics - expect to see 'MyGraphics' next");
	frame.paint(new MyGraphics());

}

class MyPanel extends JPanel {
	public void paint (Graphics g) {
		super.paint(g);
		System.out.println("Graphics is "+g);

		g.fillRect(10, 10, 20, 20);
	}
}

class MyGraphics extends Graphics {

	public String toString () {
		return "MyGraphics";
	}

	public Graphics create() {
		return this;
	}

	// I've left out the huge list of abstract methods from the original script
	// since they're unchanged from the defaults and don't really matter here.
}

RepaintManager.currentManager(frame).setDoubleBufferingEnabled(false);
frame.paint(new MyGraphics());
RepaintManager.currentManager(frame).setDoubleBufferingEnabled(true);

RepaintManager.currentManager(frame).setDoubleBufferingEnabled(false);
frame.paint(new MyGraphics());
RepaintManager.currentManager(frame).setDoubleBufferingEnabled(true);

RepaintManager.currentManager(frame).setDoubleBufferingEnabled(false);
frame.paint(new MyGraphics());
RepaintManager.currentManager(frame).setDoubleBufferingEnabled(true);