Shocky repainting and duplicate objects on screen

Question

Good day,
First of all let me say I'm not all to familiar in Desktop applications so i find myself struggling with paint and repainting problems a lot.
Now, i have a problem when i paint objects to the screen which are updated through an observer update.
I've posted most of the class Track.java(which is currently a JComponent) which contains obstacles to be painted on it. In the paint method i also draw lines to create a simple illusion of movement, thought it seems like those get updated more frequent then the obstacles (which are JPanels; I;ve also tried JLabels as i reckon repainting JPanels every 20ms might be a heavy load).
Edit: The obstacles stay in the screen sometimes; it looks like they get a duplicated object on a certain (totaly random) moment and stay there until an other object gets loaded into the `holder`. Also i mentioned in the title that the objects shocked through the screen this is the same problem as i mentioned above.
Posted the only method in Model.Car that sends a update to the track
I hope all of this makes sense and are able to give me directions which might lead to a solution.
Thanks in advance
    public Track(Model.ICar car, Model.ITrack track, View.Game game, View.Car viewCar, int limiter) {
        super();
        this.setBounds(10,10,400,400);
        this.setFocusable(true);
        this.setLayout(null);
        this.grabFocus();
        this.car           = car;
        this.track         = track;
        this.game          = game;
        this.viewCar       = viewCar;
        this.limiter       = limiter;
        this.obstaclePart  = track.getObstaclePart()/this.limiter;
        this.oilObj        = new Oil[(int)Math.floor(visibleTrackRange/obstaclePart)+2];
        this.replOilObj    = new Oil[track.getObstObstacleList().size()];
        this.barrelObj     = new Barrel[(int)Math.floor(visibleTrackRange/obstaclePart)+2];
        this.replBarrelObj = new Barrel[track.getObstObstacleList().size()];
        this.obstacleList  = new java.util.ArrayList();
        addObstacles();
        updateObstacles();
  public void paint(Graphics g) {
        super.paintComponents(g);
        if (linePos >= 600) this.linePos = 0;
        if (secLinePos >= 600) this.secLinePos = 0;
        g.setColor(c);
        g.fillRect(195, linePos, 6, 120);
        g.fillRect(391, linePos, 6, 120);
        g.fillRect(195, secLinePos, 6, 120);
        g.fillRect(391, secLinePos, 6, 120);
        if(this.finishPosition>-1) this.paintFinish(g);
        g.dispose();
    public void update(Observable o, Object arg) {
        if (o.equals(car)) {
            linePos    += (int) (car.getSpeed() / this.limiter);
            secLinePos += (int) (car.getSpeed() / this.limiter);
            yPos        = (int) (car.getY() / this.limiter);
            viewCar.thetaChanged( car.getTheta() );
            updateObstacles();
            repaint();
        } else if (o.equals(track)) {
            if (((Model.Track)o).getCollidedBool()) game.gameOver();
            else game.finish();
    public void reset() {
        this.car            = null;
        this.track          = null;
        this.game           = null;
        this.finishPosition = -1;
        removeObstacles();
        obstacleList        = null;
    // Start private methods
    private void addObstacles() {
        for(int i=0; i<Math.floor((visibleTrackRange/obstaclePart)+2); i++) {
                oilObj[i] = new Oil(game.initImage("images\\oil.png"));
                oilObj.setBounds(-500, -500, (Model.Barrel.WIDTH*60), (Model.Barrel.LENGTH*60));
this.add(oilObj[i]);
barrelObj[i] = new Barrel(game.initImage("images\\barrel.png"));
barrelObj[i].setBounds(-500, -500, (Model.Barrel.WIDTH*60), (Model.Barrel.LENGTH*60));
this.add(barrelObj[i]);
java.util.ArrayList tmpList = track.getObstObstacleList();
for(int j=0; j<tmpList.size(); j++) {
if (((Model.Obstacle)tmpList.get(j)).getType().equals("oil")) {
replOilObj[j] = new Oil(game.initImage("images\\oil.png"));
replOilObj[j].setXPos(Math.round(((Model.Obstacle)tmpList.get(j)).getposX()));
replOilObj[j].setYPos(Math.round(((Model.Obstacle)tmpList.get(j)).getposY()/10));
obstacleList.add(j, replOilObj[j]);
} else {
replBarrelObj[j] = new Barrel(game.initImage("images\\barrel.png"));
replBarrelObj[j].setXPos(Math.round(((Model.Obstacle)tmpList.get(j)).getposX()));
replBarrelObj[j].setYPos(Math.round(((Model.Obstacle)tmpList.get(j)).getposY()/10));
obstacleList.add(j, replBarrelObj[j]);
disposeReplicas();
private void disposeReplicas() {
replOilObj = null;
replBarrelObj = null;
private void updateObstacles() {
int j, obstacleIndex = (yPos -(yPos%obstaclePart))/obstaclePart;
j = 0;
for (int i = obstacleIndex; i < (obstacleIndex +(Math.floor(visibleTrackRange / obstaclePart) +2)); i++) {
if (((View.IObstacle)obstacleList.get(i)).getType().equals("oil") ) {
int normalizedY = 600 - ((((View.Oil)obstacleList.get(i)).getYPos() - yPos) * 60);
oilObj[j].setBounds((((View.Oil)obstacleList.get(i)).getXPos()) * 60, normalizedY,(Model.Oil.WIDTH * 60), (Model.Oil.LENGTH * 60));
} else {
int normalizedY = 600 - ((((View.Barrel)obstacleList.get(i)).getYPos() - yPos) * 60);
barrelObj[j].setBounds((((View.Barrel)obstacleList.get(i)).getXPos()) * 60, normalizedY,(Model.Barrel.WIDTH * 60),(Model.Barrel.LENGTH * 60));
j++;
Model.Car:public void move() {
this.y += (int)(speed/this.dividedDelay);
this.setChanged();
this.notifyObservers();
Edited by: BramBo__ on Nov 29, 2007 8:12 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                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                     

Answer 1

Cheers for the respone.
The first error, well i was messing around with the paint methods i'm still not 100% on the difference between all of them so i forgot to edit them back.
so i changed it all back to :
public void paintComponent(Graphics g) {
        super.paintComponent(g);Secondly i've looked into the layered panes, the problem is that i'll have to alter the JFrame directly. Currently this class(code below) is extended from a ImagePanel, which is an extended JPanel(code Below).
I've changed all the objects to JLabels and instead of calling setBounds im calling setLocation now, unfortunately it hasnt changed a thing. (i;ve also included a obstacle class, see below)
As i interpreted the layeredPane it just adds the functionality to add a Z-dimension to the Frame and it doesnt quite change the efficiency problem i seem to be suffering, or does it?
Track Class creation:
public class Track extends javax.swing.JComponent implements Observer ImagePanel code:
public class ImagePanel extends JPanel {
    Image bgImg;
    public ImagePanel(Image imgSrc) {
        this.bgImg = imgSrc;
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        g.drawImage(bgImg, 0, 0, this);
public class Oil extends JLabel implements View.IObstacle {
    private int xPos, yPos;
    private String type = "oil";
    public Oil(String image) {
        super(new ImageIcon(image));
        this.setOpaque(false);
        this.setPreferredSize(new Dimension((Model.Oil.WIDTH*60), (Model.Oil.LENGTH*60)));
        this.setLayout(null);
    public int getXPos()          { return xPos; }
    public int getYPos()          { return yPos; }
    public String getType()       { return type; }
    public void setXPos(int xPos) { this.xPos = xPos; }
    public void setYPos(int yPos) { this.yPos = yPos; }
}