Игра на Java

[STERVA]

Добрый всем вечер. У меня есть код игры "пятнашки", она с цифрами. Как сдлать, чтоб вместо цифр была картинка. И она собиралась. Теоретически я понимаю как это сделать, а на практике беда(((((. Выручите пожалуйста.

package info.javenue.games.pyatnashki;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.util.*;
public class Pyatnashki extends JFrame {
private JPanel panel = new JPanel(new GridLayout(4, 4, 2, 2));
private JMenuBar menu = null;
private final String fileItems[] = new String []{"New", "Exit"};
private static Random generator = new Random();
private int[][] numbers = new int[4][4];
public Pyatnashki() {
setBounds(200, 200, 300, 300);
setResizable(false);
createMenu();
setJMenuBar(menu);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
Container container = getContentPane();
init();
panel.setDoubleBuffered(true);
container.add(panel);
repaintField();}
public void init() {
int[] invariants = new int[16];
for (int i = 0; i < 4; i++) {
for (int j = 0; j < 4; j++) {
numbers[i][j] = 0;
invariants[i*4 + j] = 0; }}
for (int i = 1; i < 16; i++) {
int k;
int l;
do{
k = generator.nextInt(100) % 4;
l = generator.nextInt(100) % 4; }
while (numbers[k][l] != 0);
numbers[k][l] = i;
invariants[k*4+l] = i;}
boolean change = true;
 int counter = 1;
while (change) {
change = false;
for (int i = 0; i < 16; i++) {
if (invariants[i] != i) {
for (int j = 0; j < 16; j++) {
if (invariants[j] == i) {
int temp = invariants[i];
invariants[i] = invariants[j];
invariants[j] = temp;
change = true;
counter++;
break; } }
 break; } } }
 if (counter % 2 != 0) {
int temp = numbers[0][0];
numbers[0][0] = numbers[3][3];
numbers[3][3] = temp; }}
public void repaintField() {
panel.removeAll();
for (int i = 0; i < 4; i++) {
 for (int j = 0; j < 4; j++) {
 JButton button = new JButton(Integer.toString(numbers[i][j]));
 button.setFocusable(false);
                panel.add(button);
                if (numbers[i][j] == 0) {
                    button.setVisible(false);
                } else
                    button.addActionListener(new ClickListener()); } }
panel.validate();}
    public boolean checkWin() {
        boolean status = true;
        for (int i = 0; i < 4; i++) {
            for (int j = 0; j < 4; j++) {
                if (i == 3 && j > 2)
                    break;
                if (numbers[i][j] != i * 4 + j + 1) {
                    status = false; }  } }
        return status;}
    private void createMenu() {
        menu = new JMenuBar();
        JMenu fileMenu = new JMenu("File");
        for (int i = 0; i < fileItems.length; i++) {
            JMenuItem item = new JMenuItem(fileItems[i]);
            item.setActionCommand(fileItems[i].toLowerCase());
            item.addActionListener(new NewMenuListener());
            fileMenu.add(item);}
        fileMenu.insertSeparator(1);
  menu.add(fileMenu);}
    private class NewMenuListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            String command = e.getActionCommand();
            if ("exit".equals(command)) {
                System.exit(0); }
            if ("new".equals(command)) {
                init();
                repaintField();} }}
 private class ClickListener implements ActionListener {
        public void actionPerformed(ActionEvent e) {
            JButton button = (JButton) e.getSource();
            button.setVisible(false);
            String name = button.getText();
            change(Integer.parseInt(name));}}
    public void change(int num) {
        int i = 0, j = 0;
        for (int k = 0; k < 4; k++) {
            for (int l = 0; l < 4; l++) {
                if (numbers[k][l] == num) {
                    i = k;
                    j = l;}} }
        if (i > 0) {
            if (numbers[i - 1][j] == 0) {
                numbers[i - 1][j] = num;
                numbers[i][j] = 0;}}
        if (i < 3) {
            if (numbers[i + 1][j] == 0) {
                numbers[i + 1][j] = num;
                numbers[i][j] = 0; }}
        if (j > 0) {
            if (numbers[i][j - 1] == 0) {
                numbers[i][j - 1] = num;
                numbers[i][j] = 0;}}
        if (j < 3) {
            if (numbers[i][j + 1] == 0) {
                numbers[i][j + 1] = num;
                numbers[i][j] = 0; } }
        repaintField();
        if (checkWin()) {
JOptionPane.showMessageDialog(null, "YOU WIN!", "Congratulations", 1);
            init();
            repaintField();
            setVisible(false);
            setVisible(true);}}
    public static void main(String[] args) {
        JFrame app = new Pyatnashki();
        app.setVisible(true);}}