请用java语言写一个贪吃蛇

好的，以下是一个简单的贪吃蛇游戏的Java代码：

import java.awt.*;
import java.awt.event.*;
import javax.swing.*;

public class SnakeGame extends JFrame implements ActionListener {
    private Timer timer;
    private Snake snake;
    private Food food;
    private boolean gameOver;

    public SnakeGame() {
        setTitle("Snake Game");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setResizable(false);

        snake = new Snake();
        food = new Food(snake);
        gameOver = false;

        addKeyListener(new KeyAdapter() {
            public void keyPressed(KeyEvent e) {
                int key = e.getKeyCode();
                if (key == KeyEvent.VK_LEFT) {
                    snake.setDirection(Snake.Direction.LEFT);
                } else if (key == KeyEvent.VK_RIGHT) {
                    snake.setDirection(Snake.Direction.RIGHT);
                } else if (key == KeyEvent.VK_UP) {
                    snake.setDirection(Snake.Direction.UP);
                } else if (key == KeyEvent.VK_DOWN) {
                    snake.setDirection(Snake.Direction.DOWN);
                }
            }
        });

        timer = new Timer(100, this);
        timer.start();

        pack();
        setLocationRelativeTo(null);
        setVisible(true);
    }

    public void actionPerformed(ActionEvent e) {
        if (!gameOver) {
            snake.move();
            if (snake.collidesWith(food)) {
                snake.grow();
                food = new Food(snake);
            }
            if (snake.collidesWithItself()) {
                gameOver = true;
            }
            repaint();
        }
    }

    public void paint(Graphics g) {
        super.paint(g);
        snake.draw(g);
        food.draw(g);
        if (gameOver) {
            g.drawString("Game Over", 150, 150);
        }
    }

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

class Snake {
    public enum Direction { LEFT, RIGHT, UP, DOWN };
    private static final int BLOCK_SIZE = 10;
    private static final int INITIAL_SIZE = 5;
    private Direction direction;
    private int x[];
    private int y[];
    private int size;

    public Snake() {
        direction = Direction.RIGHT;
        x = new int[INITIAL_SIZE];
        y = new int[INITIAL_SIZE];
        size = INITIAL_SIZE;
        for (int i = 0; i < size; i++) {
            x[i] = BLOCK_SIZE * (size - i);
            y[i] = BLOCK_SIZE;
        }
    }

    public void setDirection(Direction d) {
        if ((direction == Direction.LEFT && d != Direction.RIGHT) ||
            (direction == Direction.RIGHT && d != Direction.LEFT) ||
            (direction == Direction.UP && d != Direction.DOWN) ||
            (direction == Direction.DOWN && d != Direction.UP)) {
            direction = d;
        }
    }

    public void move() {
        for (int i = size - 1; i > 0; i--) {
            x[i] = x[i - 1];
            y[i] = y[i - 1];
        }
        if (direction == Direction.LEFT) {
            x[0] -= BLOCK_SIZE;
        } else if (direction == Direction.RIGHT) {
            x[0] += BLOCK_SIZE;
        } else if (direction == Direction.UP) {
            y[0] -= BLOCK_SIZE;
        } else if (direction == Direction.DOWN) {
            y[0] += BLOCK_SIZE;
        }
    }

    public void grow() {
        size++;
        int[] newX = new int[size];
        int[] newY = new int[size];
        for (int i = 0; i < size - 1; i++) {
            newX[i] = x[i];
            newY[i] = y[i];
        }
        newX[size - 1] = x[size - 2];
        newY[size - 1] = y[size - 2];
        x = newX;
        y = newY;
    }

    public boolean collidesWith(Food food) {
        return x[0] == food.getX() && y[0] == food.getY();
    }

    public boolean collidesWithItself() {
        for (int i = 1; i < size; i++) {
            if (x[0] == x[i] && y[0] == y[i]) {
                return true;
            }
        }
        return false;
    }

    public void draw(Graphics g) {
        g.setColor(Color.GREEN);
        for (int i = 0; i < size; i++) {
            g.fillRect(x[i], y[i], BLOCK_SIZE, BLOCK_SIZE);
        }
    }
}

class Food {
    private static final int BLOCK_SIZE = 10;
    private int x;
    private int y;

    public Food(Snake snake) {
        do {
            x = (int) (Math.random() * SnakeGame.WIDTH / BLOCK_SIZE) * BLOCK_SIZE;
            y = (int) (Math.random() * SnakeGame.HEIGHT / BLOCK_SIZE) * BLOCK_SIZE;
        } while (snake.collidesWithItself() || collidesWithSnake(snake));
    }

    public int getX() {
        return x;
    }

    public int getY() {
        return y;
    }

    public boolean collidesWithSnake(Snake snake) {
        for (int i = 0; i < snake.size; i++) {
            if (x == snake.x[i] && y == snake.y[i]) {
                return true;
            }
        }
        return false;
    }

    public void draw(Graphics g) {
        g.setColor(Color.RED);
        g.fillRect(x, y, BLOCK_SIZE, BLOCK_SIZE);
    }
}

希望这个代码能够帮到你！