生成一个java版贪吃蛇游戏

好的，以下是一个简单的Java版贪吃蛇游戏：

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

public class SnakeGame extends JFrame implements ActionListener {
    private static final int ROWS = 20;
    private static final int COLS = 20;
    private static final int CELL_SIZE = 25;
    private static final int WINDOW_WIDTH = ROWS * CELL_SIZE;
    private static final int WINDOW_HEIGHT = COLS * CELL_SIZE;
    private JButton startButton = new JButton("Start");
    private JButton stopButton = new JButton("Stop");
    private JPanel buttonPanel = new JPanel();
    private JPanel gamePanel = new JPanel();
    private Timer timer;
    private int[][] gameBoard = new int[ROWS][COLS];
    private int[] snakeX = new int[ROWS * COLS];
    private int[] snakeY = new int[ROWS * COLS];
    private int snakeLength = 3;
    private int direction = KeyEvent.VK_RIGHT;
    private int foodX, foodY;
    private boolean gameOver = false;

    public SnakeGame() {
        setTitle("Snake Game");
        setSize(WINDOW_WIDTH, WINDOW_HEIGHT);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

        buttonPanel.add(startButton);
        buttonPanel.add(stopButton);
        add(buttonPanel, BorderLayout.NORTH);

        gamePanel.setBackground(Color.WHITE);
        gamePanel.setPreferredSize(new Dimension(WINDOW_WIDTH, WINDOW_HEIGHT));
        add(gamePanel, BorderLayout.CENTER);

        startButton.addActionListener(this);
        stopButton.addActionListener(this);

        addKeyListener(new KeyAdapter() {
            public void keyPressed(KeyEvent e) {
                int keyCode = e.getKeyCode();
                if (keyCode == KeyEvent.VK_LEFT || keyCode == KeyEvent.VK_RIGHT || keyCode == KeyEvent.VK_UP || keyCode == KeyEvent.VK_DOWN) {
                    direction = keyCode;
                }
            }
        });

        setResizable(false);
        setVisible(true);
    }

    public void actionPerformed(ActionEvent e) {
        Object source = e.getSource();
        if (source == startButton) {
            startGame();
        } else if (source == stopButton) {
            stopGame();
        }
    }

    private void startGame() {
        initGame();
        timer = new Timer(100, new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                moveSnake();
                checkCollision();
                repaint();
            }
        });
        timer.start();
    }

    private void stopGame() {
        timer.stop();
        gameOver = true;
        JOptionPane.showMessageDialog(this, "Game Over");
    }

    private void initGame() {
        // Initialize game board
        for (int i = 0; i < ROWS; i++) {
            for (int j = 0; j < COLS; j++) {
                gameBoard[i][j] = 0;
            }
        }

        // Initialize snake
        snakeX[0] = ROWS / 2;
        snakeY[0] = COLS / 2;
        snakeX[1] = snakeX[0] - 1;
        snakeY[1] = snakeY[0];
        snakeX[2] = snakeX[1] - 1;
        snakeY[2] = snakeY[1];
        snakeLength = 3;

        // Generate food
        generateFood();

        gameOver = false;
    }

    private void generateFood() {
        foodX = (int) (Math.random() * ROWS);
        foodY = (int) (Math.random() * COLS);
        if (gameBoard[foodX][foodY] != 0) {
            generateFood();
        }
    }

    private void moveSnake() {
        // Move snake body
        for (int i = snakeLength - 1; i > 0; i--) {
            snakeX[i] = snakeX[i - 1];
            snakeY[i] = snakeY[i - 1];
        }

        // Move snake head
        switch (direction) {
            case KeyEvent.VK_LEFT:
                snakeY[0]--;
                break;
            case KeyEvent.VK_RIGHT:
                snakeY[0]++;
                break;
            case KeyEvent.VK_UP:
                snakeX[0]--;
                break;
            case KeyEvent.VK_DOWN:
                snakeX[0]++;
                break;
        }

        // Check if snake eats food
        if (snakeX[0] == foodX && snakeY[0] == foodY) {
            // Increase snake length
            snakeLength++;

            // Generate new food
            generateFood();
        }

        // Update game board
        for (int i = 0; i < ROWS; i++) {
            for (int j = 0; j < COLS; j++) {
                gameBoard[i][j] = 0;
            }
        }
        for (int i = 0; i < snakeLength; i++) {
            gameBoard[snakeX[i]][snakeY[i]] = 1;
        }
        gameBoard[foodX][foodY] = 2;
    }

    private void checkCollision() {
        // Check if snake hits wall
        if (snakeX[0] < 0 || snakeX[0] >= ROWS || snakeY[0] < 0 || snakeY[0] >= COLS) {
            stopGame();
            return;
        }

        // Check if snake hits itself
        for (int i = 1; i < snakeLength; i++) {
            if (snakeX[0] == snakeX[i] && snakeY[0] == snakeY[i]) {
                stopGame();
                return;
            }
        }
    }

    public void paint(Graphics g) {
        super.paint(g);

        // Draw game board
        for (int i = 0; i < ROWS; i++) {
            for (int j = 0; j < COLS; j++) {
                switch (gameBoard[i][j]) {
                    case 0:
                        g.setColor(Color.WHITE);
                        break;
                    case 1:
                        g.setColor(Color.GREEN);
                        break;
                    case 2:
                        g.setColor(Color.RED);
                        break;
                }
                g.fillRect(j * CELL_SIZE, i * CELL_SIZE, CELL_SIZE, CELL_SIZE);
            }
        }
    }

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

该游戏基于 Swing UI 框架，使用了 Java 的定时器来控制游戏进程，通过监听键盘事件来改变蛇的方向。在游戏界面中，使用``JPanel``和``JButton``来创建一个简单的界面。游戏窗口的大小为20*20，每个格子的大小为25*25。游戏的主要逻辑在``startGame()``和``moveSnake()``方法中实现，其中``moveSnake()``方法控制蛇的移动和食物的生成，``startGame()``方法初始化游戏，并启动定时器。