Timed 2d animation with AWT

Question

I am making an AWT app that involves moving a series of images across the screen at a set interval.
There is a ton of code involved with this, so I am going to try to keep this as abstract as possible.
In short, the images need to traverse an 800 pixel space (horizontally) in 3715.192.... milliseconds, or 3715192743.764... nanoseconds, which is 4343990.929... nanoseconds per pixel.
Each of the images has a Point object that tracks it's current position.
The panel the objects are drawn on has a inner class that implements runnable() called Animator. The Animator waits every 4343990 ns, and iterates each object's Point.x by -1 (right to left), like this:
class Animator implements Runnable {
     WordPanel wordPanel;
     Animator(WordPanel wordPanel) {
          this.wordPanel = wordPanel;
     public void run() {
          // TODO Auto-generated method stub
          while (true){
               while (TransportState.getCurrentState()!=TransportState.TransportEventStates.STOP) {
                    long startTime = System.nanoTime();
                                // the next while loop should throttle execution of the loop to 4343990 ns
                    while ((System.nanoTime() - startTime) <= 4343990L) {
                         Thread.yield();
                    if (songFileWordImages != null && songFileWordImages.size()>0) {
                         synchronized (songFileWordImages) {
                              for (SongFileWordImage sfwi : songFileWordImages) {
                                   synchronized (sfwi) {
                                        int oldX = sfwi.getPoint().x;
                                        int oldY = sfwi.getPoint().y;
                                        sfwi.setPoint(new Point(oldX - 1, oldY));
                    wordPanel.repaint();
}Everything is back-buffered (double buffered) properly, the problem isn't flickering. The problem is with the while loop that is supposed to throttle the iteration of the x values to move the images. It seems to be waiting too long between iterations.
I arbitrarily lowered the 4343990L by half, and that made it closer to the right speed, but still too slow. From that point, I just continually arbitrarily lowered the value until it "looked right".
The problem is that I can't stand the arbitrary solution, I need to know WHY.
Testing said loop, I had it output System.nanoTime() - startTime to the screen, and found that it sometimes seemed to go "back in time". In theory, the values should have continually gotten bigger until they hit 4343990, but I noticed that it only did it generally, and that there were some non-linear values in the output. WTF?
Can someone give me some pointers on doing smooth animation in AWT without having to deal with ns? I know that Swing has some animation tools, but I want this to be 100% AWT.

Answer 1

Here is an example of using the Swing timer class, to show how simple it is:
import java.awt.*;
import java.awt.event.*;
import javax.swing.*;
public class SwingTimerTest extends JFrame implements ActionListener {
     private Timer timer;
     private JLabel label;
     private int iterCount;
     public SwingTimerTest() {
          int ms = 50; // Delay at which to repaint, in milliseconds.
          JPanel cp = new JPanel(new BorderLayout());
          cp.setBorder(BorderFactory.createEmptyBorder(5,5,5,5));
          JLabel topLabel = new JLabel("I will get updated every " + ms +
                                                  " milliseconds.");
          cp.add(topLabel, BorderLayout.NORTH);
          label = new JLabel("I have been updated 0 times.");
          cp.add(label, BorderLayout.SOUTH);
          iterCount = 0;
          timer = new Timer(ms, this);
          timer.setRepeats(true);
          timer.start();
          setContentPane(cp);
          setDefaultCloseOperation(EXIT_ON_CLOSE);
          setTitle("Swing Timer Demo");
          pack();
     // Called by our Timer at a fixed delay.
     public void actionPerformed(ActionEvent e) {
          if (e.getSource()==timer) {
               iterCount++;
               label.setText("I have been updated " + iterCount + " times.");
     public static void main(String[] args) {
          SwingUtilities.invokeLater(new Runnable() {
               public void run() {
                    new SwingTimerTest().setVisible(true);
}