用java写一个贪吃蛇代码

好的，以下是一个简单的Java贪吃蛇代码：

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

public class Snake extends JFrame implements KeyListener {

    private static final long serialVersionUID = 1L;

    private final int width = 400;
    private final int height = 400;
    private final int size = 20;
    private final int rows = height / size;
    private final int cols = width / size;

    private int snakeX, snakeY;
    private int foodX, foodY;
    private int snakeLength = 2;
    private int direction = KeyEvent.VK_RIGHT;

    private ArrayList<Integer> snakeXList = new ArrayList<Integer>();
    private ArrayList<Integer> snakeYList = new ArrayList<Integer>();

    private Timer timer;

    public Snake() {
        super("Snake");

        setPreferredSize(new Dimension(width, height));
        setResizable(false);
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        pack();
        setVisible(true);

        addKeyListener(this);

        startGame();
    }

    public void startGame() {
        snakeX = cols / 2 * size;
        snakeY = rows / 2 * size;

        snakeXList.clear();
        snakeYList.clear();

        for (int i = 0; i < snakeLength; i++) {
            snakeXList.add(snakeX - i * size);
            snakeYList.add(snakeY);
        }

        newFood();

        timer = new Timer(100, new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                moveSnake();
            }
        });

        timer.start();
    }

    public void newFood() {
        foodX = (int) (Math.random() * cols) * size;
        foodY = (int) (Math.random() * rows) * size;
    }

    public void moveSnake() {
        switch (direction) {
            case KeyEvent.VK_LEFT:
                snakeX -= size;
                break;
            case KeyEvent.VK_RIGHT:
                snakeX += size;
                break;
            case KeyEvent.VK_UP:
                snakeY -= size;
                break;
            case KeyEvent.VK_DOWN:
                snakeY += size;
                break;
        }

        snakeXList.add(0, snakeX);
        snakeYList.add(0, snakeY);

        if (snakeX == foodX && snakeY == foodY) {
            newFood();
            snakeLength++;
        } else {
            snakeXList.remove(snakeLength);
            snakeYList.remove(snakeLength);
        }

        if (snakeX < 0 || snakeX >= width || snakeY < 0 || snakeY >= height ||
            snakeXList.indexOf(snakeX) != 0 || snakeYList.indexOf(snakeY) != 0) {
            timer.stop();
            JOptionPane.showMessageDialog(this, "Game Over");
            startGame();
        }

        repaint();
    }

    public void paint(Graphics g) {
        g.setColor(Color.WHITE);
        g.fillRect(0, 0, width, height);

        g.setColor(Color.RED);
        g.fillRect(foodX, foodY, size, size);

        g.setColor(Color.BLACK);
        for (int i = 0; i < snakeLength; i++) {
            g.fillRect(snakeXList.get(i), snakeYList.get(i), size, size);
        }
    }

    public void keyPressed(KeyEvent e) {
        int newDirection = e.getKeyCode();

        if (newDirection == KeyEvent.VK_LEFT && direction != KeyEvent.VK_RIGHT ||
            newDirection == KeyEvent.VK_RIGHT && direction != KeyEvent.VK_LEFT ||
            newDirection == KeyEvent.VK_UP && direction != KeyEvent.VK_DOWN ||
            newDirection == KeyEvent.VK_DOWN && direction != KeyEvent.VK_UP) {
            direction = newDirection;
        }
    }

    public void keyReleased(KeyEvent e) {}
    public void keyTyped(KeyEvent e) {}

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

}

这个程序使用Java Swing在窗口中绘制游戏界面，使用ArrayList来存储蛇的位置，使用Java Timer来控制蛇的移动。你可以使用键盘上的方向键来控制蛇的方向，吃到食物后蛇的长度会增加。当蛇碰到墙壁或自己时，游戏结束。