Checkers - BoardSquare

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

/**
*
* Square class is an inherited class of JButton representing squares on the
* Checkers board. Each square is a JButton allowing the user to click and move
* Checkers.
*
* @author
* Date: 07/09/2014
*/

public class BoardSquare extends JButton
{
    static BoardSquare[][] boardSquares = new BoardSquare[8][8]; //array of boardSquares each of JButton type.
    Checker checkerOnSquare; //contains information about the checker on this square. null if no checker.
    private final boolean isRedSquare; //colour of square

    //images of red and black checkers, both kinged and unkinged
    private static final ImageIcon redKing = new ImageIcon("Images/redKingImage.png");
    private static final ImageIcon blackKing = new ImageIcon("Images/blackKingImage.png");
    private static final ImageIcon redChecker = new ImageIcon("Images/redCheckerImage.png");
    private static final ImageIcon blackChecker = new ImageIcon("Images/blackCheckerImage.png");

    /**
     * Single constructor for Square objects.
     *
     * @param isRed a boolean parameter determining attributes such as colour and direction of movement.
     * If isRed is false, square is assumed to be black.
     */
    public BoardSquare(boolean isRed, int row , int col)
    {
        super(); //takes on JButton attributes
        this.setOpaque(true); //minor detail
        this.setMargin(new Insets(0, 0, 0, 0)); //inset margin
        this.isRedSquare = isRed;
        if (isRed){
            this.setBackground(new Color(220, 43, 43)); //sets background of red squares
        }
        else{
            this.setBackground(new Color(40, 5, 5)); //sets background of black squares
        }
    }

    /**
     * Sets the board up at the start of the game.
     * Makes use of refresh() method.
     */
    public static void initialise()
    {
        for (int i = 0; i < boardSquares.length; i++)
        {
            for (int j = 0; j < boardSquares[i].length; j++)
            {
                if (i<=2 && (i+j)%2 == 0) //sets up checkers at far end of board
                {
                    //Checker instantiation: first param - isRed, second param - isKing
                    //Checker is obviously not king at start of game.
                    boardSquares[j][i].checkerOnSquare = new Checker(true, false);
                }
                else if (i>=5 && (i+j)%2 == 0) //checkers at near end of board.
                {
                    boardSquares[j][i].checkerOnSquare = new Checker(false, false);
                }
            }
        }
        GameWindow.timer.start(); //clock starts couting.
        refresh(); //see doc for refresh() method.
    }

    /**
     * Refreshes the board by checking what Checker object (can be null) is
     * contained by each boardSquare and appropriately sets that square's icon
     * appropriately. Note that each square is an object of JButton.
     */
    private static void refresh()
    {
        for (int i = 0; i < boardSquares.length; i++)
        {
            for (int j = 0; j < boardSquares[i].length; j++)
            {
                if(boardSquares[j][i].checkerOnSquare != null){ //this means there is no checker on the square.
                    if (boardSquares[j][i].checkerOnSquare.isRed){
                        if (boardSquares[j][i].checkerOnSquare.isKing){
                            boardSquares[j][i].setIcon(resizeIcon(64, 64, redKing)); //red and king
                        }
                        else{
                        boardSquares[j][i].setIcon(resizeIcon(64, 64, redChecker)); //red and not king.
                        }
                    }
                    else if(!boardSquares[j][i].checkerOnSquare.isRed){
                        if(boardSquares[j][i].checkerOnSquare.isKing){
                            boardSquares[j][i].setIcon(resizeIcon(64, 64, blackKing)); //black and king.
                        }
                        else{
                            boardSquares[j][i].setIcon(resizeIcon(64, 64, blackChecker)); //black and not king.
                        }
                    }
                }
            }
        }
    }

    /**
     * Helper method to refresh that resizes the checkers icons so that they fit
     * snugly within the board squares.
     *
     * @param width is the width of the icon.
     * @param height is the height of the icon.
     * @param icon is the icon to be resized to new width and height.
     * @return an ImageIcon similar to the parameter imageIcon, but resized.
     */
    private static ImageIcon resizeIcon(int width, int height, ImageIcon icon)
    {
        Image img = icon.getImage();
        Image newimg = img.getScaledInstance(width, height, java.awt.Image.SCALE_SMOOTH);
        icon = new ImageIcon(newimg);
        return icon;
    }
}