用java写一个贪吃蛇小游戏

当然可以！这里是一个简单的贪吃蛇小游戏的Java代码示例：

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

public class SnakeGame extends JFrame {

    private Snake snake;
    private Timer timer;
    private boolean gameOver;

    public SnakeGame() {
        setTitle("贪吃蛇游戏");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setResizable(false);
        setSize(400, 400);
        setLocationRelativeTo(null);
        
        snake = new Snake();
        
        addKeyListener(new KeyAdapter() {
            @Override
            public void keyPressed(KeyEvent e) {
                snake.keyPressed(e.getKeyCode());
            }
        });
        
        timer = new Timer(100, new ActionListener() {
            @Override
            public void actionPerformed(ActionEvent e) {
                if (!gameOver) {
                    snake.move();
                    if (snake.collidedWithSelf() || snake.collidedWithWall()) {
                        gameOver = true;
                    }
                    repaint();
                }
            }
        });
        
        timer.start();
        
        setVisible(true);
    }
    
    @Override
    public void paint(Graphics g) {
        super.paint(g);
        
        if (gameOver) {
            g.setColor(Color.RED);
            g.setFont(new Font("Arial", Font.BOLD, 20));
            g.drawString("游戏结束", 150, 180);
        } else {
            snake.draw(g);
        }
    }
    
    public static void main(String[] args) {
        new SnakeGame();
    }
}

class Snake {

    private static final int UNIT_SIZE = 20;
    private static final int GAME_UNITS = (400 * 400) / (UNIT_SIZE * UNIT_SIZE);
    private static final int DELAY = 100;
    
    private int[] x;
    private int[] y;
    private int bodyParts;
    private int appleX;
    private int appleY;
    private char direction;
    private boolean moving;
    
    public Snake() {
        x = new int[GAME_UNITS];
        y = new int[GAME_UNITS];
        
        bodyParts = 6;
        direction = 'R';
        
        generateApple();
        
        moving = true;
    }
    
    public void generateApple() {
        appleX = (int) (Math.random() * (400 / UNIT_SIZE)) * UNIT_SIZE;
        appleY = (int) (Math.random() * (400 / UNIT_SIZE)) * UNIT_SIZE;
    }
    
    public void draw(Graphics g) {
        for (int i = 0; i < bodyParts; i++) {
            if (i == 0) {
                g.setColor(Color.GREEN);
                g.fillRect(x[i], y[i], UNIT_SIZE, UNIT_SIZE);
            } else {
                g.setColor(new Color(45, 180, 0));
                g.fillRect(x[i], y[i], UNIT_SIZE, UNIT_SIZE);
            }
        }
        
        g.setColor(Color.RED);
        g.fillOval(appleX, appleY, UNIT_SIZE, UNIT_SIZE);
    }
    
    public void move() {
        for (int i = bodyParts; i > 0; i--) {
            x[i] = x[i - 1];
            y[i] = y[i - 1];
        }
        
        switch (direction) {
            case 'U':
                y[0] -= UNIT_SIZE;
                break;
            case 'D':
                y[0] += UNIT_SIZE;
                break;
            case 'L':
                x[0] -= UNIT_SIZE;
                break;
            case 'R':
                x[0] += UNIT_SIZE;
                break;
        }
        
        if (x[0] == appleX && y[0] == appleY) {
            bodyParts++;
            generateApple();
        }
        
        moving = true;
    }
    
    public boolean collidedWithSelf() {
        for (int i = bodyParts; i > 0; i--) {
            if (x[0] == x[i] && y[0] == y[i]) {
                return true;
            }
        }
        return false;
    }
    
    public boolean collidedWithWall() {
        return x[0] < 0 || x[0] >= 400 || y[0] < 0 || y[0] >= 400;
    }
    
    public void keyPressed(int keyCode) {
        switch (keyCode) {
            case KeyEvent.VK_UP:
                if (!moving) {
                    direction = 'U';
                    moving = true;
                }
                break;
            case KeyEvent.VK_DOWN:
                if (!moving) {
                    direction = 'D';
                    moving = true;
                }
                break;
            case KeyEvent.VK_LEFT:
                if (!moving) {
                    direction = 'L';
                    moving = true;
                }
                break;
            case KeyEvent.VK_RIGHT:
                if (!moving) {
                    direction = 'R';
                    moving = true;
                }
                break;
        }
    }
}

这个代码示例使用Java的Swing库来创建窗口和绘制游戏界面。贪吃蛇的移动由定时器控制，当贪吃蛇与自身或墙壁发生碰撞时游戏结束。你可以尝试运行这段代码，体验一下这个简单的贪吃蛇小游戏！