Conway's game of life visualisation implemented using JavaFX

ConwayGameOfLife.java

/*
This code implements Conway's game of life, the universe of which is a two dimensional grid of cells which can either be dead or alive.
The grid changes its state based on these rules:
1) Any live cell with fewer than two live neighbours dies, as if caused by underpopulation.
2) Any live cell with two or three live neighbours lives on to the next generation.
3) Any live cell with more than three live neighbours dies, as if by overpopulation.
4) Any dead cell with exactly three live neighbours becomes a live cell, as if by reproduction.
In this case, color of a live cell is black and color of a dead cell is white.
Sample input 1:
10
10
1
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 1 0 0 0 0 0
0 0 0 0 1 1 0 0 0 0
0 0 0 0 1 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
Sample input 2:
10
10
1
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 1 1 0 0
0 0 0 0 0 0 0 1 0 0
0 0 0 0 1 0 0 0 0 0
0 0 0 0 1 1 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0
Sample input 3:
20
20
2
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
Sample input 4:
20
20
2
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0
0 0 0 0 1 1 0 0 1 1 0 0 0 0 0 0 0 0 0 0
0 0 0 0 1 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 1 1 1 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0
 */

import javafx.animation.KeyFrame;
import javafx.animation.Timeline;
import javafx.application.Application;
import javafx.event.ActionEvent;
import javafx.event.EventHandler;
import javafx.scene.Scene;
import javafx.scene.shape.Rectangle;
import javafx.scene.layout.StackPane;
import javafx.stage.Stage;
import javafx.scene.paint.Color;
import javafx.scene.layout.GridPane;
import javafx.util.Duration;

import java.util.Scanner;

public class ConwayGameOfLife extends Application {
    static boolean grid[][];
    static int number_of_rows, number_of_columns;

    @Override
    public void start(Stage primary_stage) {

        Scanner sc = new Scanner(System.in);
        toPrint("Enter the number of rows:");
        number_of_rows = sc.nextInt();
        toPrint("Enter the number of columns:");
        number_of_columns = sc.nextInt();
        toPrint("Enter the refresh rate:");
        double refresh_rate = sc.nextDouble();

        grid = new boolean[number_of_rows][number_of_columns];

        toPrint("Enter the initial grid values:");
        initializeGrid(sc);

        GridPane grid_pane = createGridOfRectangles();
        StackPane root = new StackPane();
        root.getChildren().add(grid_pane);

        Scene scene = new Scene(root, 300, 250);
        primary_stage.setTitle("Conway Game of Life");
        primary_stage.setScene(scene);
        primary_stage.show();

        Timeline timeline = new Timeline(new KeyFrame(Duration.millis(1000.0 / refresh_rate),
                new EventHandler<ActionEvent>() {
                    @Override
                    public void handle(ActionEvent actionEvent) {
                        updateGrid();
                        GridPane grid_pane = createGridOfRectangles();
                        root.getChildren().add(grid_pane);
                    }
                }));
        timeline.setCycleCount(Timeline.INDEFINITE);
        timeline.play();
    }

    public static void initializeGrid(Scanner sc) {
        for (int i = 0; i < number_of_rows; i++)
            for (int j = 0; j < number_of_columns; j++) {
                if (sc.nextInt() == 0)
                    grid[i][j] = false;
                else
                    grid[i][j] = true;
            }
    }

    public static void updateGrid() {
        boolean new_grid[][] = new boolean[number_of_rows][number_of_columns];
        for (int i = 0; i < number_of_rows; i++)
            for (int j = 0; j < number_of_columns; j++) {
                int live_neighbours = countLiveNeighbours(i,j);
                new_grid[i][j] = false;
                if((grid[i][j] && live_neighbours == 2) || live_neighbours == 3)
                    new_grid[i][j] = true;
            }

        grid = new_grid;
    }

    public static int countLiveNeighbours(int i, int j) {
        int k, l, live_neighbours = 0;
        for(k = -1; k <= 1; k++)
            for(l = -1; l <= 1; l++)
                if(k != 0 || l != 0)
                    live_neighbours = live_neighbours + checkLiveOrNot(k+i,l+j);

        return live_neighbours;
    }

    public static int checkLiveOrNot(int i, int j) {
        if(i < number_of_rows && i >= 0 && j < number_of_columns && j >= 0)
            if(grid[i][j])
                return 1;

        return 0;
    }

    public static GridPane createGridOfRectangles() {
        GridPane grid_pane = new GridPane();
        for (int i = 0; i < number_of_rows; i++) {
            for (int j = 0; j < number_of_columns; j++) {
                System.out.println(grid[i][j]);
                Rectangle r = new Rectangle();
                r.setWidth(10);
                r.setHeight(10);
                if (grid[i][j]) {
                    r.setFill(Color.BLACK);
                    grid_pane.add(r, i, j, 1, 1);
                } else {
                    r.setFill(Color.WHITE);
                    grid_pane.add(r, i, j, 1, 1);
                }
            }
        }
        return grid_pane;
    }

    public static void toPrint(String str) {
        System.out.println(str);
    }

    public static void main(String[] args) {
        launch(args);
    }
}