Displaying a Grid

Question

I need a grid that i can move objects around in
I need to have a 10 by 10 grid where 30% of the spaces are occupied by object (15% red and 15% blue). The object will only be able to stay in that square if it's neighbours are predominantly the same colour. if that is not the case than the object must be moved ot an adjacent square.
Thanks, any help would be appreciated!

Answer 1

import java.awt.*;
import java.awt.event.*;
import java.awt.geom.*;
import java.util.Random;
import javax.swing.*;
public class ProxiGrid extends JPanel {
    int[][] grid;
    final int PAD = 20;
    public ProxiGrid() {
        grid = new int[10][10];
        initializeGrid();
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        Graphics2D g2 = (Graphics2D)g;
        g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING,
                            RenderingHints.VALUE_ANTIALIAS_ON);
        double w = getWidth();
        double h = getHeight();
        double xInc = (w - 2*PAD)/grid[0].length;
        double yInc = (h - 2*PAD)/grid.length;
        for(int j = 0; j < grid.length; j++) {
            double y = PAD + j*yInc;
            for(int k = 0; k < grid[j].length; k++) {
                if(grid[j][k] == 0) continue;
                Color color = grid[j][k] == 1 ? Color.red : Color.blue;
                g2.setPaint(color);
                double x = PAD + k*xInc;
                g2.fill(new Rectangle2D.Double(x, y, xInc, yInc));
        g2.setPaint(Color.black);
        double x1 = PAD, y1, x2 = w-PAD, y2 = h-PAD;
        for(int j = 0; j <= grid.length; j++) {
            y1 = PAD + j*yInc;
            g2.draw(new Line2D.Double(x1, y1, x2, y1));
        y1 = PAD;
        for(int j = 0; j <= grid[0].length; j++) {
             x1 = PAD + j*xInc;
             g2.draw(new Line2D.Double(x1, y1, x1, y2));
    private void initializeGrid() {
        Random seed = new Random();
        fillSquares(1, seed);
        fillSquares(2, seed);
    private void fillSquares(int n, Random seed) {
        int count = 0;
        while(count < 15) {
            int row = seed.nextInt(grid.length);
            int col = seed.nextInt(grid[0].length);
            if(isEmpty(row, col)) {
                grid[row][col] = n;
                count++;
    private boolean isEmpty(int row, int col) {
        return grid[row][col] == 0;
    public static void main(String[] args) {
        ProxiGrid test = new ProxiGrid();
        JFrame f = new JFrame();
        f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        f.getContentPane().add(test);
        f.setSize(400,400);
        f.setLocation(200,200);
        f.setVisible(true);
}