用Java写贪吃蛇

好的，以下是一个简单的Java贪吃蛇游戏的代码示例：

import java.awt.Color;
import java.awt.Graphics;
import java.awt.Point;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.ArrayList;
import java.util.Random;
import javax.swing.JFrame;
import javax.swing.JPanel;

public class SnakeGame extends JPanel implements Runnable, KeyListener {
    private static final long serialVersionUID = 1L;
    private static final int WIDTH = 500;
    private static final int HEIGHT = 500;
    private Thread thread;
    private boolean running;
    private boolean right = true, left = false, up = false, down = false;
    private BodyPart b;
    private ArrayList<BodyPart> snake;
    private int xCoor = 10, yCoor = 10, size = 5;
    private int ticks = 0;
    private Point apple;
    private Random random;
    private int score;
    
    public SnakeGame() {
        setFocusable(true);
        addKeyListener(this);
        setPreferredSize(new Dimension(WIDTH, HEIGHT));
        random = new Random();
        snake = new ArrayList<BodyPart>();
        start();
    }
    
    public void start() {
        running = true;
        thread = new Thread(this);
        thread.start();
    }
    
    public void stop() {
        running = false;
        try {
            thread.join();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }
    
    public void tick() {
        if (snake.size() == 0) {
            b = new BodyPart(xCoor, yCoor, 10);
            snake.add(b);
        }
        ticks++;
        if (ticks > 250000) {
            if (right) xCoor++;
            if (left) xCoor--;
            if (up) yCoor--;
            if (down) yCoor++;
            
            ticks = 0;
            
            b = new BodyPart(xCoor, yCoor, 10);
            snake.add(b);
            
            if (snake.size() > size) {
                snake.remove(0);
            }
        }
        
        if (apple != null) {
            if (xCoor == apple.x && yCoor == apple.y) {
                size++;
                score++;
                apple.setLocation(random.nextInt(49) * 10, random.nextInt(49) * 10);
            }
        } else {
            apple = new Point(random.nextInt(49) * 10, random.nextInt(49) * 10);
        }
        
        for (int i = 0; i < snake.size(); i++) {
            if (xCoor == snake.get(i).getxCoor() && yCoor == snake.get(i).getyCoor()) {
                if (i != snake.size() - 1) {
                    stop();
                }
            }
        }
        
        if (xCoor < 0 || xCoor > 49 || yCoor < 0 || yCoor > 49) {
            stop();
        }
    }
    
    public void paint(Graphics g) {
        g.clearRect(0, 0, WIDTH, HEIGHT);
        g.setColor(Color.BLACK);
        g.fillRect(0, 0, WIDTH, HEIGHT);
        
        g.setColor(Color.WHITE);
        g.drawString("Score: " + score, 10, 20);
        
        for (int i = 0; i < snake.size(); i++) {
            snake.get(i).draw(g);
        }
        
        g.setColor(Color.RED);
        g.fillRect(apple.x, apple.y, 10, 10);
        
        g.setColor(Color.WHITE);
        g.drawRect(0, 0, WIDTH - 1, HEIGHT - 1);
    }
    
    public void run() {
        while (running) {
            tick();
            repaint();
        }
    }
    
    public void keyPressed(KeyEvent e) {
        int key = e.getKeyCode();
        if (key == KeyEvent.VK_RIGHT && !left) {
            right = true;
            up = false;
            down = false;
        }
        if (key == KeyEvent.VK_LEFT && !right) {
            left = true;
            up = false;
            down = false;
        }
        if (key == KeyEvent.VK_UP && !down) {
            up = true;
            left = false;
            right = false;
        }
        if (key == KeyEvent.VK_DOWN && !up) {
            down = true;
            left = false;
            right = false;
        }
    }
    
    public void keyReleased(KeyEvent e) {}
    public void keyTyped(KeyEvent e) {}
    
    public static void main(String[] args) {
        JFrame frame = new JFrame();
        SnakeGame snakeGame = new SnakeGame();
        frame.add(snakeGame);
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setTitle("Snake Game");
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }
}

class BodyPart {
    private int xCoor, yCoor, width, height;
    
    public BodyPart(int xCoor, int yCoor, int tileSize) {
        this.xCoor = xCoor;
        this.yCoor = yCoor;
        width = tileSize;
        height = tileSize;
    }
    
    public void tick() {}
    
    public void draw(Graphics g) {
        g.setColor(Color.GREEN);
        g.fillRect(xCoor * width, yCoor * height, width, height);
    }
    
    public int getxCoor() {
        return xCoor;
    }
    
    public void setxCoor(int xCoor) {
        this.xCoor = xCoor;
    }
    
    public int getyCoor() {
        return yCoor;
    }
    
    public void setyCoor(int yCoor) {
        this.yCoor = yCoor;
    }
}

这个代码中，我们用到了Java的Swing库来创建游戏窗口和绘制游戏界面。SnakeGame类继承了JPanel类，并实现了Runnable和KeyListener接口。在start()方法中，我们启动了一个新的线程来运行游戏逻辑。在tick()方法中，我们处理了蛇的移动、吃苹果、撞墙、碰到自己等情况，并更新游戏状态。在paint()方法中，我们绘制了游戏界面。在keyPressed()方法中，我们处理了用户的方向键输入，并更新蛇的移动方向。最后，在main()方法中，我们创建了一个JFrame对象，并将SnakeGame添加到其中，然后显示窗口。