Java 2D Game - Use Canvas Without Extending It

Java Code:

public class Game extends Canvas implements Runnable, KeyListener {
private static final long serialVersionUID = 1L;

public Game() {
setMinimumSize(new Dimension(width, height));
setMaximumSize(new Dimension(width, height));
setPreferredSize(new Dimension(width, height));
}

[code]...

I want to remove the extends Canvas from the top line and when I use JFrame to add canvas, I don't do add.(this, but instead I do add a canvas variable I make. So instead of extending I want to make a variable. But then how would I do the start, stop and run?I want to use Graphics, Canvas (Not Jpanel because I want to use BufferedImage) & JFrame. I don't want to extend Canvas, how could I use Canvas identically to shown above but instead of extending using it as a variable? or, how could I do this?