用java写一个贪吃蛇游戏

A:

下面是一个简单的贪吃蛇游戏的Java代码，注释中有详细解释。这个代码实现了一个基础的轮廓，你可以根据自己的需要添加更多的功能。

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

public class SnakeGame extends JFrame implements KeyListener {

    // 游戏面板的大小
    private static final int WIDTH = 20, HEIGHT = 20;

    // 蛇的长度、蛇的位置、食物的位置
    private int length;
    private int[] snakeX = new int[WIDTH * HEIGHT];
    private int[] snakeY = new int[WIDTH * HEIGHT];
    private int foodX;
    private int foodY;

    // 方向
    private boolean up, down, left, right;

    // 游戏是否进行中
    private boolean isPlaying;

    public SnakeGame() {
        // 初始化
        isPlaying = true;
        length = 3;
        up = false;
        down = false;
        left = false;
        right = true;

        // 设置窗口属性
        setTitle("贪吃蛇小游戏");
        setSize(500, 500);
        setLocationRelativeTo(null);
        setDefaultCloseOperation(EXIT_ON_CLOSE);

        // 添加键盘监听器
        addKeyListener(this);

        // 设置画布属性
        JPanel gamePanel = new JPanel();
        gamePanel.setPreferredSize(new Dimension(500, 500));
        gamePanel.setBackground(Color.gray);
        add(gamePanel);

        // 设置食物的位置
        generateFood();

        // 开始游戏
        playGame(gamePanel);
    }

    // 绘制游戏面板
    public void drawGamePanel(Graphics g) {
        // 绘制蛇的头部和身体
        for (int i = 0; i < length; i++) {
            if (i == 0) {
                g.setColor(Color.red);
                g.fillRect(snakeX[i] * 20, snakeY[i] * 20, 20, 20);
            } else {
                g.setColor(Color.green);
                g.fillRect(snakeX[i] * 20, snakeY[i] * 20, 20, 20);
            }
        }

        // 绘制食物
        g.setColor(Color.yellow);
        g.fillRect(foodX * 20, foodY * 20, 20, 20);
    }

    // 生成食物
    public void generateFood() {
        foodX = (int) (Math.random() * WIDTH);
        foodY = (int) (Math.random() * HEIGHT);
    }

    // 游戏逻辑
    public void playGame(JPanel gamePanel) {
        while (isPlaying) {
            try {
                Thread.sleep(100);
            } catch (InterruptedException e) {
                e.printStackTrace();
            }

            // 移动蛇的身体
            for (int i = length; i > 0; i--) {
                snakeX[i] = snakeX[i - 1];
                snakeY[i] = snakeY[i - 1];
            }

            // 移动蛇的头部
            if (up) snakeY[0]--;
            if (down) snakeY[0]++;
            if (left) snakeX[0]--;
            if (right) snakeX[0]++;

            // 判断是否吃到食物
            if (snakeX[0] == foodX && snakeY[0] == foodY) {
                length++;
                generateFood();
            }

            // 判断是否撞墙或撞到自己
            if (snakeX[0] < 0 || snakeX[0] >= WIDTH || snakeY[0] < 0 || snakeY[0] >= HEIGHT) {
                isPlaying = false;
                JOptionPane.showMessageDialog(gamePanel, "游戏结束！");
            }
            for (int i = 1; i < length; i++) {
                if (snakeX[i] == snakeX[0] && snakeY[i] == snakeY[0]) {
                    isPlaying = false;
                    JOptionPane.showMessageDialog(gamePanel, "游戏结束！");
                }
            }

            // 重新绘制游戏面板
            gamePanel.repaint();
        }
    }

    // 键盘事件
    @Override
    public void keyPressed(KeyEvent e) {
        int key = e.getKeyCode();

        if (key == KeyEvent.VK_UP && !down) {
            up = true;
            right = false;
            left = false;
        }
        if (key == KeyEvent.VK_DOWN && !up) {
            down = true;
            right = false;
            left = false;
        }
        if (key == KeyEvent.VK_LEFT && !right) {
            left = true;
            up = false;
            down = false;
        }
        if (key == KeyEvent.VK_RIGHT && !left) {
            right = true;
            up = false;
            down = false;
        }
    }

    @Override
    public void keyReleased(KeyEvent e) {
    }

    @Override
    public void keyTyped(KeyEvent e) {
    }

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