Probleme affichage Graphics et Graphics2D

public class Panneaubis extends JPanel {

  private float posX = -50;
  private float posY = -50;
  private float posX2 = -50;
  private float posY2 = -50;



public  void paintcomponent(Graphics g1){
	  	super.paintComponents(g1);
		 Graphics2D g = (Graphics2D) g1;
		 //super.paintComponents(g);
		 g.setColor(Color.BLACK);
		 g.drawRect(0, 0, 100, 100);
		 g.drawString("courbe", 100, 100);
		 g.setBackground(Color.cyan);
	     g.setColor(Color.red);
	     g.drawOval((int) posX, (int) posY, 50, 50);
	     g.draw(new Line2D.Float(posX, posY, posX2, posY2));
  }

  public float getPosX() {
    return posX;
  }

  public void setPosX(float x1) {
    this.posX = x1;
  }

  public float getPosY() {
    return posY;
  }

  public void setPosY(float posY) {
    this.posY = posY;
  }

/**

 
 @return the posX2 */protected float getPosX2() {	return posX2;}/** * @param posX2 the posX2 to set */protected void setPosX2(float posX2) {	this.posX2 = posX2;}/** * @return the posY2 */protected float getPosY2() {	return posY2;}/** * @param posY2 the posY2 to set */protected void setPosY2(float posY2) {	this.posY2 = posY2;}        }

public class Panneau extends JPanel {
  private int posX = -50;
  private int posX2 = -50;
  private int posY = -50;
  private int posY2 = -50;

  public void paintComponent(Graphics g){
	  //super.paintComponent(g);
      g.setColor(Color.red);
      g.fillOval(posX, posY, 20, 20);
      g.drawLine(posX, posY, posX2, posY2);
      g.setColor(Color.YELLOW);
      g.drawLine(20, 0, 20, 300);
      g.drawLine(0, 240, 1000, 240);
  }

  public int getPosX() {
    return posX;
  }

  public void setPosX(int posX) {
    this.posX = posX;
  }

  public int getPosY() {
    return posY;
  }

  public void setPosY(int posY) {
    this.posY = posY;
  }

/**

 
 @return the posX2 */protected int getPosX2() {	return posX2;}/** * @param posX2 the posX2 to set */protected void setPosX2(int posX2) {	this.posX2 = posX2;}/** * @return the posY2 */protected int getPosY2() {	return posY2;}/** * @param posY2 the posY2 to set */protected void setPosY2(int posY2) {	this.posY2 = posY2;}        }

private  void traceCourbe(float xMax, float yMax, JTable tableau){
			afficheCourbe.removeAll();
			afficheCourbe.updateUI();
			Panneau courbe = new Panneau();
			afficheCourbe.add(courbe);
			// Tracer la courbe point par point
				float y= 220/(yMax*1.1f);
				float x = 800/(xMax*1.1f);
				System.out.println("x=: "+x+"y= : "+y+"  "+xMax+ "    "+yMax);
				int j = 0;
				SwingWorker sw = new SwingWorker(){
					 protected Object doInBackground() throws Exception {
						 float x1,x2,y1,y2;
						 int j = 0;
							do {
			            	    x1 = 20f +(float) tableau.getValueAt(j, 1)*x;
				            	x2 = 20f +(float) tableau.getValueAt(j+1, 1)*x;
				            	y1 = 220 - (float) tableau.getValueAt(j, 2)*y;
				            	y2 = 220 -(float) tableau.getValueAt(j+1, 2)*y;
								System.out.println(x1+"  "+x2+"  "+y1+"  "+y2);
				            	courbe.setPosX((int)x1);
								courbe.setPosY((int)y1);
								courbe.setPosX2((int)x2);
								courbe.setPosY2((int)y2);
								courbe.validate();
								courbe.revalidate();
								courbe.repaint();
								courbe.setOpaque(true);
						      try {
						        Thread.sleep(100);
						      } catch (InterruptedException e) {
						        e.printStackTrace();
						      }
								j++;
								//System.out.println(courbe.getPosX()+"     "+courbe.getPosX2()+"      "+courbe.getPosY()+"     "+courbe.getPosY2());
							}while (y2>20);
							return null;
		            		}
					 public void done(){            
					        if(SwingUtilities.isEventDispatchThread())
					          System.out.println("Dans l'EDT ! ");
					          //courbe.repaint();
					      }         
					    };
					    sw.execute();
        }