import javax.swing.*;
import java.awt.*;

class Affiche extends JComponent {

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);

        if (isOpaque()) {
            g.setColor(getBackground());
            g.fillRect(0, 0, getWidth(), getHeight());
        }

        Graphics2D pinceau = (Graphics2D) g.create();

        int pionTaille = 50;
        int pas = 70;
        int yBase = 60;
        int tabJeu[][] = {{0,0,1,2,0,0,0,0,0},
                          {0,1,2,1,2,0,0,0,0},
                          {0,2,1,2,1,2,1,0,0},
                          {0,1,2,1,2,1,2,1,2},
                          {1,2,1,2,0,2,1,2,1},
                          {2,1,2,1,2,1,2,1,0},
                          {0,0,1,2,1,2,1,2,0},
                          {0,0,0,0,2,1,2,1,0},
                          {0,0,0,0,0,2,1,0,0}};

        for (int i = 0; i < pionsParLigne.length; i++) {
            int nbPions = pionsParLigne[i];
            int x = 60 + decalageLigne[i];
            int y = yBase + i * pas;

            for (int j = 0; j < nbPions; j++) {
                if ((i+j) % 2 == 0)
                    pinceau.setColor(Color.BLUE);
                else
                    pinceau.setColor(Color.RED);

                pinceau.fillOval(x + j * pas, y, pionTaille, pionTaille);
            }
        }

        pinceau.dispose();
    }

    public static void main(String[] args) {
        JFrame fenetre = new JFrame("Forme diagonale miroir");
        fenetre.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        fenetre.setSize(900, 800);
        fenetre.add(new Affiche());
        fenetre.setVisible(true);
    }
}