Canvas

[Suse]

Hey!
ich will eine Canvas erstellen und hab dazu folgende Subklasse geschrieben:

class Canvas extends java.awt.Canvas
    {

private JFrame frame;
        private CanvasPane canvas;
        private Graphics2D graphic;
        private Color backgroundColour;
        private Image canvasImage;

public Canvas()
        {
            super();
        }

public void drawLine(int x1, int y1, int x2, int y2)
        {
            graphic.drawLine(x1, y1, x2, y2);
            canvas.repaint();
        }

public void drawString(String text, int x, int y)
        {
            graphic.drawString(text, x, y);
            canvas.repaint();
        }

public void setForegroundColour(Color newColour)
        {
            graphic.setColor(newColour);
        }

private class CanvasPane extends JPanel
        {
            public void paint(Graphics g)
            {
                g.drawImage(canvasImage, 0, 0, null);
            }

}

}

was ist daran falsch??