How to make smooth hardware accelerated JApplet?

Question

Hi there ive made a game that extends JPanel and im using the paintComponent method to do my painting
as far as i know JPanel is hardware accelerated by default bufferStrategy(2)
ive put the JPanel in a JFrame and the game runs very smooth with ~62fps and cpu usage is <10%
then i tried putting the JPanel in JApplet and opened it in firefoxbrowser and the fps says ~59fps and cpu usage ~30% but its super skippy and looks like its drawing incorrectly like some of the objects are displaced very far from where they are supposed to be some frames and drawn perfectly some other frames. What's happening? Is there anyway to fix this?
Below is some code that for a JApplet and JFrame they both contain the JPanel and ive packed everything in a jar file that can be run as a desktopapp or japplet
I've also tried add the JApplet directly into the JFrame but it seems the performance might go down a little (though im not sure how much)
main extends JApplet
RobotValkyrieAttack extends JPanel
package RobotValkyrieAttack;
import javax.swing.*;
import java.awt.*;
import java.util.*;
import java.awt.event.*;
public class main extends JApplet{
     static LinkedList<Image> listImage;
     //no JApplet constructor is allowed to be overrriden
     public void init(){ //called by the japplet container
          this.loadImages();
          RobotValkyrieAttack r = new RobotValkyrieAttack(listImage);
          this.add(r);
          Thread t = new Thread(r);
          t.start();
          this.addKeyListener(r);
     public void loadImages(){
          //images
          listImage = new LinkedList<Image>();
          listImage.add( new ImageIcon(this.getClass().getResource("data/valkyrie0.png")).getImage() );
          listImage.add( new ImageIcon(this.getClass().getResource("data/astroid0.png")).getImage() );
          listImage.add( new ImageIcon(this.getClass().getResource("data/clouds0.jpg")).getImage() );
          listImage.add( new ImageIcon(this.getClass().getResource("data/cloud0.png")).getImage() );
          listImage.add( new ImageIcon(this.getClass().getResource("data/cloud1.png")).getImage() );
          listImage.add( new ImageIcon(this.getClass().getResource("data/cloud2.png")).getImage() );
          MediaTracker mt = new MediaTracker(this);
          for(int i=0; i<listImage.size(); i++){
               mt.addImage(listImage.get(i),0);
          try{
               mt.waitForAll();
          catch(Exception ex){
               ex.printStackTrace();
     public void update(Graphics g){
          this.paint(g);
     public static void main(String args[]){
          JFrame j = new JFrame();
          j.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
          j.setSize(1200,700);
          j.setLocationRelativeTo(null);
          main m = new main();
          m.loadImages();
          RobotValkyrieAttack r = new RobotValkyrieAttack(listImage);
          j.add(r);
          Thread t = new Thread(r);
          t.start();
          j.addKeyListener(r);
          main m = new main();
          m.init();
          j.add(m);
          j.setVisible(true);
}

Answer 1

Before we begin, note that performance of Java graphics has always been a bit 'hit and miss' in the sense that the same box with the same hardware and Java version can show radically different FPS rates if the video driver is updated.
For better help sooner, post an SSCCE.
Applet SSCCEs that involve images are a problem. Normally I would invite creators of image based SSCCEs to hot-link to [images available off my site|http://pscode.org/media/#image], but an applet cannot hot-link to images. It will be necessary to generate the images in code, if you want much chance of people running the code. Note that very few people will follow a link to anywhere, or download any 'build zip' or similar, to help out on a problem.
That code snippet as posted, had a number of things that seemed horrific.
- A class called 'main'. O_o Better would be AppletRenderTest which is not only more descriptive, but also uses the common nomenclature for a class name.
- Frame size 1200x700?! It pays to ensure any 'comparison' of applet and application is done at the same size and my screen size is 1024x768. Make it a lot smaller, like 800x600.
- A Swing based Timer is more typically used for Swing animation, than a Thread/Runnable.
- GUI construction should be done on the EDT.
- This..
//no JApplet constructor is allowed to be overrriden..is not only factually wrong, but also incorrectly spelt.
I am not confident you are up to writing:
- Test code (especially test code you intend others to help with)
- GUIs
- Animation code
- Applets
Or if you are capable of parts of that, of combining the 4.
Are you confident?