probleme d'affichage dans JPanel

bonjour tout le monde


voici mon code




import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Container;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.util.Random;

import javax.swing.ImageIcon;
import javax.swing.JButton;
import javax.swing.JComboBox;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class MonPanel extends JFrame
{
private int[][]adjascence;
private int som,nba,n,m,m1,x,y,xx,yy,a=0,a1=2;
private boolean iterX=false, iterY=false,stop=false;
private Graphics g;
private JPanel Pan;

MonPanel(int[][]adjascence1, int som1,int nba1)
{

adjascence=adjascence1;
som=som1;
nba=nba1;


setContentPane(new JPanelImageBg("Image/VG.gif" ));
//setDefaultCloseOperation(JFrame.DO_NOTHING_ON_CLOSE);
setIconImage(new ImageIcon("Image/icone.GIF" ).getImage());
setFont(new Font("Tahoma",Font.BOLD,12));
setTitle("Visualisation graphique" );
setSize(906,633);
setLocationRelativeTo(null);
//setDefaultCloseOperation(2);
setResizable(false);
setVisible(true);




Container contentPane = getContentPane();
contentPane.setLayout(new BorderLayout());

Pan=new JPanel();
Pan.setVisible(true);
Pan.setBackground(Color.red);
Pan.setBounds(20,20,200,200);

contentPane.add(RA);
contentPane.add(RS);
contentPane.add(OK);
contentPane.add(Pan);

Container contentPane1 = getContentPane();
contentPane1.setLayout(new BorderLayout());


//g=this.getGraphics();


}
public void paintComponent(Graphics g1)
{
g=g1;
g=Pan.getGraphics();
setBounds(27, 38, 842,473);
setBackground(Color.white);

g.setFont(new Font("Tahoma",Font.BOLD,14));
y=10;
x=10;
xx=30;
yy=15;
m=2;
a1=2;
for(int i=0;i<som;i++)
{

// La liste des cerles dessinés


g.setColor(new Color(47,44,44));
g.fillRect(x,y,xx,yy);



y=y+40;
if(iterX==true)
{
x=x+20;
iterX=false;
}
else
{

x=x+30;
iterX=true;
}

if(x>820) {if(stop==false){ x=m*3; m=m+a1; stop=true;a1=a1-1;}else {stop=false; x=m*4; m=m-3; a1=a1+2;} }
if(x<30) x=x+19;
if(y>440)
{
if(iterY==false)
{
y=35;
iterY=true;
}
else
{
y=10;
iterY=false;
}


if(iterX==false)
{
x=x+40;
iterX=true;
}
else
{
x=x+15;
iterX=false;
}


}


}

}


}



mais j'ai un probléme dans l'affichage
c-à-d les cercles ne s'affichent pas

où est le probleme

mercià vous tous

pardon mais je n'ai pas compris