game of life version 2 repaired

/*
 * Copyright © Progmasters (QTC Kft.), 2016-2018.
 * All rights reserved. No part or the whole of this Teaching Material (TM) may be reproduced, copied, distributed,
 * publicly performed, disseminated to the public, adapted or transmitted in any form or by any means, including
 * photocopying, recording, or other electronic or mechanical methods, without the prior written permission of QTC Kft.
 * This TM may only be used for the purposes of teaching exclusively by QTC Kft. and studying exclusively by QTC Kft.’s
 * students and for no other purposes by any parties other than QTC Kft.
 * This TM shall be kept confidential and shall not be made public or made available or disclosed to any unauthorized person.
 * Any dispute or claim arising out of the breach of these provisions shall be governed by and construed in accordance with the laws of Hungary.
 */

import java.util.Random;

public class GameOfLife {

    private int mx, my;
    private int[][] space;

    public GameOfLife(int maximumX, int maximumY) {
        this.mx = maximumX;
        this.my = maximumY;
        this.space = new int[maximumX][maximumY];
    }
    public void updateToNextGeneration() {
        int[][] nextGeneration = new int[Main.HEIGHT][Main.WIDTH];
        for (int row = 0; row < this.mx; row++) {
            for (int column = 0; column < this.my; column++) {
                switch (countNeighbourCells(row, column)) {
                    case 3:
                        nextGeneration[row][column] = 1;
                        break;
                    case 2:
                        nextGeneration[row][column] = this.space[row][column];
                        break;
                    default:
                        nextGeneration[row][column] = 0;
                }
            }
        }
        this.space = nextGeneration;
    }

    private int countNeighbourCells(int row, int column) {
        int cellNeighbourCounter = 0;
        for (int relativeRow = -1; relativeRow <= 1; relativeRow++) {
            for (int relativeColumn = -1; relativeColumn <= 1; relativeColumn++) {
                if (isCellPositionValid(row, column, relativeRow, relativeColumn) &&
                        !(relativeColumn == 0 && relativeRow == 0)) {
                    cellNeighbourCounter += this.space[row + relativeRow][column + relativeColumn];
                }
            }
        }
        return cellNeighbourCounter;
    }
    public boolean isAlive(int row, int column) {

        return this.space[row][column] == 1;
    }
    public boolean isCellPositionValid(int actualRow, int actualColumn, int relativeRow, int relativeColumn) {

        return (relativeRow + actualRow < this.mx-1 && relativeRow + actualRow > 0)
                && (relativeColumn + actualColumn > 0 && relativeColumn + actualColumn < this.my-1);
    }
    public void generateInitialBoard() {
        SpaceData.initSpace = new int[Main.HEIGHT][Main.WIDTH];
        Random random = new Random();
        for (int row = 0; row < this.mx; row++) {
            for (int column = 0; column < this.my; column++) {
                SpaceData.initSpace[row][column] = random.nextBoolean() ? 1 : 0;
            }
        }

        space = SpaceData.initSpace;
    }
    public int getMx() {
        return mx;
    }
    public int getMy() {
        return my;
    }
}