Thread: Assign variable to coordinate pair for GUI

I have a GUI grid of squares that I prompt the user for the size of (2^n). Then I ask for the coordinates to put a white square or 'hole' in the grid. I am having trouble putting the user inputted 'hole' into my grid and coloring it white.

My program prompts the user for a power of 2 grid, and displays it. But I've been trying for a couple hours to try and put the 'hole' into my grid and can't seem to get it.
How how do I take these coordinates and place the specified coordinates as a white square?

Here is my code:

import java.util.*;
import java.awt.*;
import javax.swing.*;
class trominoWarZ{
        private int currentNum;
        private int[][] grid;
    public static void main(String[] args) {
 
        Scanner input = new Scanner(System.in);
 
        System.out.println("What size board do you want?");
        double pw = input.nextDouble();
 
        System.out.println("Coordinates of missing square?");
        int x = input.nextInt();
        int y = input.nextInt(); 
 
        myHole hole = new myHole(x,y);     //WANT TO SET x,y coord to WHITE 
 
        super.drawHole(g,x,y);      
 
        myPan panel = new myPan(pw);      //this is how it reads size of board
 
        JFrame application = new JFrame();
        application.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        application.add(panel);           
        application.setSize(400, 400);
        application.setVisible(true); 
    }
}
 
class myPan extends JPanel{
 
    public double pow;
    public double hc;
 
    public static void drawHole(Graphics g, int x, int y) {    
    g.setColor(Color.WHITE);
    g.fillRect(g,x,y);
 
    }
    public myPan(double p){
        pow = p;
    }
 
    public myHole(int h){
        hc = h;                     //I will have the var hc to use for the hole
        drawHole(hc);
    }    
    public void paintComponent(Graphics g){
 
        super.paintComponent(g);   
        double num = Math.pow(2,pow);
        double across;
        double up;
        if(hc % 2 == 0){ //is a square
            across = Math.hc(num,0.5);
            up = across;
        }
        else{
            double x = Math.floor(hc/2);
            double y = x + 1;
            across = Math.hc(2,x);
            up = Math.hc(2,y);
        }
 
        if(pow % 2 == 0){ //is a square
            across = Math.pow(num,0.5);
            up = across;
        }
        else{
            double x = Math.floor(pow/2);
            double y = x + 1;
            across = Math.pow(2,x);
            up = Math.pow(2,y);
        }
        double wid = 400/across; //width of one
        double hi = 400/up; //height of one
        double nowX = 0;
        double nowY = 0;
        for(int i = 0; i < up; i++){ //top to bottom
            nowX = 0;
            for(int j = 0; j < across; j++){
                //System.out.print("*");
                g.setColor(Color.BLACK);
                g.drawRect((int)nowX, (int)nowY, (int)wid, (int)hi);
                nowX = nowX + wid;
            }
            nowY = nowY + hi;
            //System.out.print("\n");
        }
 
        //grid or whatever = g.fill
    }
    }
 
 
 
//     public static void tromino(int size, int x, int y) {
//             int actualsize = 1;
//             while (actualsize < size) actualsize*=2;
// }