使用java 编写一个贪吃蛇的游戏

好的，下面是使用 Java 编写的贪吃蛇游戏代码：

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

public class SnakeGame extends JFrame implements KeyListener {

    private JPanel gamePanel;
    private JLabel scoreLabel;
    private int score;
    private int direction;
    private Timer timer;
    private boolean gameOver;
    private int width = 20;
    private int height = 20;
    private int blockSize = 20;
    private int[][] field = new int[width][height];
    private int[] snakeX = new int[width * height];
    private int[] snakeY = new int[width * height];
    private int snakeLength;

    public SnakeGame() {
        setTitle("贪吃蛇游戏");
        setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
        setResizable(false);
        setSize(width * blockSize + 20, height * blockSize + 70);
        setLocationRelativeTo(null);

        gamePanel = new JPanel();
        gamePanel.setBackground(Color.WHITE);
        gamePanel.setFocusable(true);
        gamePanel.addKeyListener(this);
        getContentPane().add(gamePanel, BorderLayout.CENTER);

        scoreLabel = new JLabel("得分: 0");
        getContentPane().add(scoreLabel, BorderLayout.SOUTH);

        initGame();

        setVisible(true);
    }

    private void initGame() {
        gameOver = false;
        score = 0;
        direction = KeyEvent.VK_RIGHT;
        snakeLength = 3;
        snakeX[0] = width / 2;
        snakeY[0] = height / 2;
        snakeX[1] = snakeX[0] - 1;
        snakeY[1] = snakeY[0];
        snakeX[2] = snakeX[1] - 1;
        snakeY[2] = snakeY[1];
        generateFood();

        timer = new Timer(200, new ActionListener() {
            public void actionPerformed(ActionEvent e) {
                moveSnake();
                repaint();
                if (gameOver) {
                    timer.stop();
                    JOptionPane.showMessageDialog(SnakeGame.this, "游戏结束，得分: " + score);
                }
            }
        });
        timer.start();
    }

    private void generateFood() {
        int x, y;
        do {
            x = (int)(Math.random() * width);
            y = (int)(Math.random() * height);
        } while (field[x][y] != 0);
        field[x][y] = 2;
    }

    private void moveSnake() {
        int dx = 0, dy = 0;
        switch (direction) {
            case KeyEvent.VK_UP: dy = -1; break;
            case KeyEvent.VK_DOWN: dy = 1; break;
            case KeyEvent.VK_LEFT: dx = -1; break;
            case KeyEvent.VK_RIGHT: dx = 1; break;
        }
        int newHeadX = snakeX[0] + dx;
        int newHeadY = snakeY[0] + dy;
        if (newHeadX < 0 || newHeadX >= width || newHeadY < 0 || newHeadY >= height) {
            gameOver = true;
            return;
        }
        if (field[newHeadX][newHeadY] == 1) {
            gameOver = true;
            return;
        }
        if (field[newHeadX][newHeadY] == 2) {
            score++;
            scoreLabel.setText("得分: " + score);
            generateFood();
            snakeLength++;
        }
        for (int i = snakeLength - 1; i > 0; i--) {
            snakeX[i] = snakeX[i - 1];
            snakeY[i] = snakeY[i - 1];
        }
        snakeX[0] += dx;
        snakeY[0] += dy;
        for (int i = 0; i < width; i++)
            for (int j = 0; j < height; j++)
                field[i][j] = 0;
        for (int i = 0; i < snakeLength; i++)
            field[snakeX[i]][snakeY[i]] = 1;
    }

    public void paint(Graphics g) {
        super.paint(g);
        for (int i = 0; i < width; i++)
            for (int j = 0; j < height; j++) {
                if (field[i][j] == 2) {
                    g.setColor(Color.RED);
                    g.fillRect(i * blockSize, j * blockSize, blockSize, blockSize);
                }
                if (field[i][j] == 1) {
                    g.setColor(Color.BLACK);
                    g.fillRect(i * blockSize, j * blockSize, blockSize, blockSize);
                }
            }
    }

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

    public void keyReleased(KeyEvent e) {}

    public void keyTyped(KeyEvent e) {}

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

}

运行上述代码，即可开始游戏。