Using getRect method to obtain the bounding rectangle for an oval

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


class GridPanel extends JPanel implements MouseListener
{
	int numCols;
	int numRows;
	
	int numRow = -1;
	int numCol = -1;
	
	public void mouseReleased(MouseEvent event) 
	{
	
		System.out.println("mouse realeased");
	
	}
	
	public void mousePressed(MouseEvent event) 
	{
		
		System.out.println("Mouse has been pressed");
	
	}

	public void mouseClicked(MouseEvent event) 
	{
		int x = event.getX();
		int y = event.getY();
		
		
		
		System.out.println("the x position is " + x);
		System.out.println("the y position is " + y);
		System.out.println("the grid possition is: " + numRow + ", " + numCol);
			
	}
	
	public void mouseEntered(MouseEvent event) 
	{
	
		System.out.println("Mouse has been activated");
	
	}
	
	public void mouseExited(MouseEvent event) 
	{
	
		System.out.println("You're outside the area");
	
	}


	public GridPanel(int nc, int nr)
	{
		numCols = nc;
		numRows = nr;
		addMouseListener(this);
	}

	Rectangle getRect(int thisCol, int thisRow)
	{
		// if input is out of range, return "null"
		if(thisCol <0 || thisRow < 0)
			return null;
		if(thisCol>=numCols || thisRow>=numRows)
			return null;

		// otherwise, make and return the Rectangle
		int w = getWidth()/numCols;
		int h = getHeight()/numRows;

		int x = thisCol*w;
		int y = thisRow*h;

		Rectangle myRect = new Rectangle(x,y,w,h);
		return myRect;
	}

	public void paint(Graphics g)
	{
		g.setColor(Color.gray);
		g.fillRect(0,0,getWidth(), getHeight());
		g.setColor(Color.black);
		
		g.setcolor(Color.red);
		g.fillOval(x,y,getWidth(),getHeight();
		
		g.setcolor(Color.black);


		Graphics2D g2 = (Graphics2D)g;
		// we'll use Graphics2D for it's "draw" method -
		// neater than the Graphics "drawRect" suppled
		// (which you could also use)

		for (int i = 0;i<numCols;i++)
		{
			for(int j = 0;j<numRows;j++)
			{
				Rectangle r = getRect(i,j);
				g2.draw(r);
			}
		}
	}


	// copied from the W2MouseEvents for convenience
	// (so we can run the program from GridPanel class too!)
	public static void main(String[] args)
	{
		W2MouseEvents w = new W2MouseEvents();
		w.setVisible(true);
	}

}