Rysowanie tablicy dwuwymiarowej na ekranie

Jestem w trakcie pisania gry Snake. Utworzyłem sobie w klasie GameBoard tablice dwuwymiarową typu enum: CellData, która przechowywuje dane co się znajduje na danej pozycji(wąż, jabłko, ściana, pusta). Problem z tym że nie mogę sobie poradzić z wyświetleniem tego w oknie.
Plansza ma być czarna, a wąż,jabłko i ściany białe. Skrawek kodu, który podałem jest błędny i tu jest moje pytanie. Jak go poprawić, żeby działał prawidłowo.

public class GameBoard {
    private int boardWidth = 990;
    private int boardHeight = 690;
    private int xCells = boardWidth / 10 + 2;
    private int yCells = boardHeight / 10 + 2;
    private CellData board[][];
    public GameBoard() {
        board = new CellData[xCells][yCells];
        for (int i = 0; i < xCells; i++) {
            board[i][0] = CellData.WALL;
        }
        for (int i = 0; i < xCells; i++) {
            board[i][yCells-1] = CellData.WALL;
        }
        for (int j = 0; j < yCells; j++) {
            board[0][j] = CellData.WALL;
        }
        for (int j = 0; j < yCells; j++) {
            board[xCells-1][j] = CellData.WALL;
        }
    }
    public void cleanBoard() {
        for (int i = 1; i < xCells-1; i++) {
            for (int j = 1; j < yCells-1; j++) {
                board[i][j] = CellData.EMPTY;
            }
        }
    }
.............
}

public class GameInstant extends JFrame {
    private JPanel scorePanel;
    public JLabel scoreLabel;
    private CellData[][] board;
    private int score = 0;
    SnakeGame snakeRules = new SnakeGame();
    GameBoard gameBoard = new GameBoard();
    public GameInstant() {
        addKeyListener(new KeyListener() {
        ............});

        DrawingTheBoard gamePanel = new DrawingTheBoard(board);
        this.add(gamePanel, BorderLayout.CENTER);

        scorePanel = new JPanel();
        scoreLabel = new JLabel();
        scoreLabel.setText("Score: " + Integer.toString(score));
        scoreLabel.setFont(new Font("Serif", Font.PLAIN, 40));
        scorePanel.add(scoreLabel, BorderLayout.CENTER);
        this.add(scorePanel, BorderLayout.PAGE_END);



        ScheduledThreadPoolExecutor executor = new ScheduledThreadPoolExecutor(5);
        executor.scheduleAtFixedRate(new RepaintTheBoard(this), 0, snakeRules.getGameSpeed(), TimeUnit.MILLISECONDS);
        this.setVisible(true);
    }


}

class DrawingTheBoard extends JComponent {
            CellData[][] board;
            GameBoard gameBoard = new GameBoard();
            SnakeGame sGame = new SnakeGame();
            public DrawingTheBoard(CellData[][] board) {
                this.board = board;
                this.setSize(1000, 800);
            }
            public void paint(Graphics g) {
                Graphics2D g2D = (Graphics2D) g;
                g2D.setBackground(Color.BLACK);
                g2D.fillRect(0, 0, gameBoard.getxCells() * 10, gameBoard.getyCells() * 10);
                g2D.setPaint(Color.WHITE);
                sGame.update();
                for (int i = 0; i < gameBoard.getxCells(); i++) {
                    for (int j = 0; j < gameBoard.getyCells(); j++) {
                        if (board[i][j] == CellData.WALL || board[i][j] == CellData.SNAKE || board[i][j] == CellData.APPLE)
                            g2D.fillRect(i*10,j*10,10,10);
                    }
                }
    }
}