Labyrinth Game

Change the following code so that it checks the following 3 conditions:

1. there is no space between each cells (imgs)

2. even if it is resized, the components wouldn't disappear

3. The GameGUI JPanel takes all the JFrame space, so that there shouldn't be extra space appearing in the frame other than the game.

Main():

        Labyrinth labyrinth = new Labyrinth(10);

        Player player = new Player(9, 0);
        Dragon dragon = new Dragon(9, 9);

        JFrame frame = new JFrame("Labyrinth Game");
        GameGUI gui = new GameGUI(labyrinth, player, dragon);

        frame.add(gui);
        frame.setSize(600, 600);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setVisible(true);

public class GameGUI extends JPanel {
    private final Labyrinth labyrinth;
    private final Player player;
    private final Dragon dragon; //labyrinth, player, dragon are just public classes

    private final ImageIcon playerIcon = new ImageIcon("data/images/player.png");
    private final ImageIcon dragonIcon = new ImageIcon("data/images/dragon.png");
    private final ImageIcon wallIcon = new ImageIcon("data/images/wall.png");
    private final ImageIcon emptyIcon = new ImageIcon("data/images/empty.png");

    public GameGUI(Labyrinth labyrinth, Player player, Dragon dragon) {
        this.labyrinth = labyrinth;
        this.player = player;
        this.dragon = dragon;

        setFocusable(true);
        addKeyListener(new KeyAdapter() {
            @Override
            public void keyPressed(KeyEvent e) {
                char move = switch (e.getKeyCode()) {
                    case KeyEvent.VK_W -> 'W';
                    case KeyEvent.VK_S -> 'S';
                    case KeyEvent.VK_A -> 'A';
                    case KeyEvent.VK_D -> 'D';
                    default -> ' ';
                };

                if (move != ' ') {
                    player.move(move, labyrinth);
                    dragon.move(labyrinth);
                    repaint();
                    checkGameState();
                }
            }
        });
    }

    private void checkGameState() {
        if (player.getX() == labyrinth.getSize() - 1 && player.getY() == labyrinth.getSize() - 1) {
            JOptionPane.showMessageDialog(this, "You escaped! Congratulations!");
            System.exit(0);
        }

        if (Math.abs(player.getX() - dragon.getX()) <= 1 &&
            Math.abs(player.getY() - dragon.getY()) <= 1) {
            JOptionPane.showMessageDialog(this, "The dragon caught you! Game Over.");
            System.exit(0);
        }
    }

    @Override
    protected void paintComponent(Graphics g) {
        super.paintComponent(g);
        int cellSize = 50;

        for (int i = 0; i < labyrinth.getSize(); i++) {
            for (int j = 0; j < labyrinth.getSize(); j++) {
                if (labyrinth.getCell(i, j).isWall()) {
                    wallIcon.paintIcon(this, g, j * cellSize, i * cellSize);
                } else if(!labyrinth.getCell(i, j).isWall()){
                    emptyIcon.paintIcon(this, g, j * cellSize, i * cellSize);
                }
            }
        }

        playerIcon.paintIcon(this, g, player.getY() * cellSize, player.getX() * cellSize);
        dragonIcon.paintIcon(this, g, dragon.getY() * cellSize, dragon.getX() * cellSize);
    }
}