Java - Folosire JLayeredPane si GridLayout

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

public class GridPlusLayer
{
    int nr_linii=0,nr_coloane=0;
    JFrame frame;
    JLabel label,labelAfisare, superLabel;
    int x=10,y=10;
    public static void main(int x,int y)
    {
        GridPlusLayer gui=new GridPlusLayer(x,y);
    }
   

    GridPlusLayer(int x,int y)
    {
        if(x>=0&&y>=0)
        nr_linii=x;
        nr_coloane=y;      
        frame=new JFrame("Butoane");
        frame.setSize(nr_linii*75,nr_coloane*75);
        JLayeredPane layer=new JLayeredPane();
        JPanel panel=new JPanel();
        panel.setLayout(new GridLayout(nr_linii,nr_coloane));
        labelAfisare=new JLabel("Nimic");
                  
        for(int i=0;i<(nr_linii*nr_coloane);i++)
        {
            
            label=new JLabel("");
            label.setOpaque(true);
   
            int red=(int )(Math.random()*255);
            int green=(int )(Math.random()*255);
            int blue=(int )(Math.random()*255);
            Color random=new Color(red,green,blue);
            Color complementary=new Color (255-red,255-green,255-blue);
            labelAfisare.setOpaque(true);
            labelAfisare.setBackground(complementary);
            
            label.setBackground(random);
            label.setText(""+(i+1));
            panel.add(label);
     
            
        }
        superLabel=new JLabel();
        superLabel.setOpaque(true);
        superLabel.setBounds(x,y,(int)(nr_linii*75*0.5),(int)(nr_coloane*75*0.5));
        panel.setBounds(0,0,frame.getWidth(),frame.getHeight());
        layer.add(panel,JLayeredPane.DEFAULT_LAYER);
        layer.add(superLabel,JLayeredPane.PALETTE_LAYER);
        
        frame.add(layer,BorderLayout.CENTER);
        frame.add(labelAfisare,BorderLayout.NORTH);
        frame.setVisible(true);
        frame.setLocationRelativeTo(null);
        layer.addMouseListener(new List());
    }
    class List  implements MouseListener
    {
        public void mousePressed(MouseEvent e) 
        {
            x=e.getX();
            y=e.getY();
           superLabel.setBounds(x,y,(int)(nr_linii*75*0.5),(int)(nr_coloane*75*0.5));
           labelAfisare.setText("X: "+e.getX()+" Y: "+e.getY());
        }
        
        public void mouseReleased(MouseEvent e) {}
        public void mouseClicked(MouseEvent e) {}
        public void mouseEntered(MouseEvent e) {}
        public void mouseExited(MouseEvent e) {}
    }
}