用java写一个贪吃蛇

好的，下面是一个简单的 Java 贪吃蛇游戏示例代码，希望对你有所帮助：

import java.awt.Color;
import java.awt.Dimension;
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.List;
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;

    public static final int WIDTH = 300;
    public static final int HEIGHT = 300;

    private Thread thread;
    private boolean running;

    private Point head;
    private List<Point> tail;
    private Point food;

    private int direction;
    private int score;

    public SnakeGame() {
        setPreferredSize(new Dimension(WIDTH, HEIGHT));
        setBackground(Color.BLACK);
        setFocusable(true);

        addKeyListener(this);

        init();
    }

    private void init() {
        head = new Point(WIDTH / 2, HEIGHT / 2);
        tail = new ArrayList<Point>();
        tail.add(new Point(head.x - 10, head.y));
        tail.add(new Point(head.x - 20, head.y));
        tail.add(new Point(head.x - 30, head.y));
        food = new Point(getRandomX(), getRandomY());
        direction = KeyEvent.VK_RIGHT;
        score = 0;
    }

    private int getRandomX() {
        Random r = new Random();
        return r.nextInt(WIDTH / 10) * 10;
    }

    private int getRandomY() {
        Random r = new Random();
        return r.nextInt(HEIGHT / 10) * 10;
    }

    public void start() {
        running = true;
        thread = new Thread(this);
        thread.start();
    }

    public void stop() {
        running = false;
        try {
            thread.join();
        } catch (InterruptedException e) {
            e.printStackTrace();
        }
    }

    @Override
    public void run() {
        while (running) {
            update();
            repaint();
            try {
                Thread.sleep(100);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }
        }
    }

    private void update() {
        switch (direction) {
        case KeyEvent.VK_UP:
            head = new Point(head.x, head.y - 10);
            break;
        case KeyEvent.VK_DOWN:
            head = new Point(head.x, head.y + 10);
            break;
        case KeyEvent.VK_LEFT:
            head = new Point(head.x - 10, head.y);
            break;
        case KeyEvent.VK_RIGHT:
            head = new Point(head.x + 10, head.y);
            break;
        }
        if (head.x < 0 || head.x >= WIDTH || head.y < 0 || head.y >= HEIGHT) {
            gameOver();
        }
        for (Point p : tail) {
            if (p.equals(head)) {
                gameOver();
            }
        }
        tail.add(0, head);
        if (head.equals(food)) {
            score++;
            food = new Point(getRandomX(), getRandomY());
        } else {
            tail.remove(tail.size() - 1);
        }
    }

    private void gameOver() {
        stop();
        System.out.println("Game over!");
    }

    @Override
    public void paintComponent(Graphics g) {
        super.paintComponent(g);

        g.setColor(Color.WHITE);
        g.drawString("Score: " + score, 10, 20);

        g.setColor(Color.RED);
        g.fillRect(food.x, food.y, 10, 10);

        g.setColor(Color.GREEN);
        for (Point p : tail) {
            g.fillRect(p.x, p.y, 10, 10);
        }
    }

    @Override
    public void keyPressed(KeyEvent e) {
        if (e.getKeyCode() == KeyEvent.VK_UP && direction != KeyEvent.VK_DOWN) {
            direction = KeyEvent.VK_UP;
        } else if (e.getKeyCode() == KeyEvent.VK_DOWN && direction != KeyEvent.VK_UP) {
            direction = KeyEvent.VK_DOWN;
        } else if (e.getKeyCode() == KeyEvent.VK_LEFT && direction != KeyEvent.VK_RIGHT) {
            direction = KeyEvent.VK_LEFT;
        } else if (e.getKeyCode() == KeyEvent.VK_RIGHT && direction != KeyEvent.VK_LEFT) {
            direction = KeyEvent.VK_RIGHT;
        }
    }

    @Override
    public void keyReleased(KeyEvent e) {}

    @Override
    public void keyTyped(KeyEvent e) {}

    public static void main(String[] args) {
        JFrame frame = new JFrame("Snake Game");
        frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        frame.setResizable(false);
        frame.getContentPane().add(new SnakeGame());
        frame.pack();
        frame.setLocationRelativeTo(null);
        frame.setVisible(true);
    }
}

这是一个简单的贪吃蛇游戏，包括移动、食物、得分和游戏结束等基本功能。你可以在此基础上进行修改和完善，实现更多功能。