What is the best way to double buffer in this case and how to do it....

Question

currently I have
public class Frame1 extends JFrame{
//inside this class I call up circle class, rectangle class, etc.... to draw
}I am making a "paint" program, and I have individual classes to handle the paint methods heres an example:
abstract public class Shape {
    public Shape() {
    public abstract void draw(Graphics g, Color c, int x, int y, int width,int height);
}and then....
public class Circle extends Shape{
    public Circle() {
    public void draw(Graphics g, Color c, int oldx, int oldy, int newx, int newy) {
        g.setColor(c);
        g.drawOval(Math.min(oldx, newx), Math.min(oldy, newy), Math.abs(oldx - newx), Math.abs(oldy - newy));
}There is also a Rectangle class, line class.... etc! So my question to you is the following... what is the best way to implement double buffer in the individual classes? And how to do it?? And also.... the drawings should be kept inside a jPanel.
Any bit of help is much appreciated Thank you!!

Answer 1

You don't need to do double-buffering. Swing
components are double-buffered by default. Just make
sure you override paintComponent() and not paint().
And even if you had to, why would there be any
difference in implementation for your classes whether
they paint to on- or off-screen graphics?I need to override paintComponent()? what if I don't...
I am using JBuilder2005 and they automate somethings for me. So thats how they did it when they created the application they did this....
public class Frame1 extends JFrame{
/*** all my code here***/
public class Application1 {
    boolean packFrame = false;
     * Construct and show the application.
    public Application1() {
        Frame1 frame = new Frame1();
        // Validate frames that have preset sizes
        // Pack frames that have useful preferred size info, e.g. from their layout
        if (packFrame) {
            frame.pack();
        } else {
            frame.validate();
        // Center the window
        Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
        Dimension frameSize = frame.getSize();
        if (frameSize.height > screenSize.height) {
            frameSize.height = screenSize.height;
        if (frameSize.width > screenSize.width) {
            frameSize.width = screenSize.width;
        frame.setLocation((screenSize.width - frameSize.width) / 2,
                          (screenSize.height - frameSize.height) / 2);
        frame.setVisible(true);
        try {
            jbInit();
        } catch (Exception ex) {
            ex.printStackTrace();
     * Application entry point.
     * @param args String[]
    public static void main(String[] args) {
        SwingUtilities.invokeLater(new Runnable() {
            public void run() {
                try {
                    UIManager.setLookAndFeel(UIManager.
                                             getSystemLookAndFeelClassName());
                } catch (Exception exception) {
                    exception.printStackTrace();
                new Application1();
    private void jbInit() throws Exception {
}