请用javafx写一段贪吃蛇代码，要求能存档并记录最高分

以下是基于JavaFX的贪吃蛇代码，包括存档和最高分记录功能：

import javafx.animation.AnimationTimer;
import javafx.application.Application;
import javafx.geometry.Pos;
import javafx.scene.Scene;
import javafx.scene.canvas.Canvas;
import javafx.scene.canvas.GraphicsContext;
import javafx.scene.control.Alert;
import javafx.scene.control.ButtonType;
import javafx.scene.control.Label;
import javafx.scene.input.KeyCode;
import javafx.scene.layout.BorderPane;
import javafx.scene.layout.HBox;
import javafx.scene.paint.Color;
import javafx.stage.Stage;

import java.io.*;
import java.util.*;

public class SnakeGame extends Application {

    // 游戏界面大小
    private static final int WIDTH = 640;
    private static final int HEIGHT = 480;

    // 贪吃蛇格子大小
    private static final int CELL_SIZE = 10;

    // 游戏画布
    private Canvas canvas;
    private GraphicsContext gc;

    // 贪吃蛇
    private List<Cell> snake;
    private Cell head;
    private Cell food;

    // 移动方向
    private Direction direction = Direction.RIGHT;

    // 游戏状态
    private boolean gameOver = false;

    // 最高分
    private int highScore;

    @Override
    public void start(Stage primaryStage) {
        // 加载最高分
        loadHighScore();

        // 创建游戏界面
        BorderPane root = new BorderPane();
        HBox topBox = new HBox();
        topBox.setAlignment(Pos.CENTER);
        topBox.setSpacing(10);
        Label scoreLabel = new Label("Score: 0");
        Label highScoreLabel = new Label("High Score: " + highScore);
        topBox.getChildren().addAll(scoreLabel, highScoreLabel);
        root.setTop(topBox);

        // 创建游戏画布
        canvas = new Canvas(WIDTH, HEIGHT);
        gc = canvas.getGraphicsContext2D();
        root.setCenter(canvas);

        // 初始化贪吃蛇
        initSnake();

        // 监听键盘事件
        canvas.setOnKeyPressed(event -> {
            if (event.getCode() == KeyCode.UP && direction != Direction.DOWN) {
                direction = Direction.UP;
            } else if (event.getCode() == KeyCode.DOWN && direction != Direction.UP) {
                direction = Direction.DOWN;
            } else if (event.getCode() == KeyCode.LEFT && direction != Direction.RIGHT) {
                direction = Direction.LEFT;
            } else if (event.getCode() == KeyCode.RIGHT && direction != Direction.LEFT) {
                direction = Direction.RIGHT;
            }
        });

        // 创建游戏循环
        AnimationTimer timer = new AnimationTimer() {
            private long lastTime = 0;

            @Override
            public void handle(long now) {
                if (lastTime == 0) {
                    lastTime = now;
                    return;
                }

                if (gameOver) {
                    stop();
                    gameOver();
                    return;
                }

                if (now - lastTime < 1000000000 / 10) {
                    return;
                }

                lastTime = now;

                moveSnake();
                drawSnake();
                checkCollision();
                checkFood();
                scoreLabel.setText("Score: " + (snake.size() - 1));
            }
        };

        // 创建开始按钮
        ButtonType newGameButtonType = new ButtonType("New Game");
        ButtonType continueButtonType = new ButtonType("Continue");
        Alert alert = new Alert(Alert.AlertType.NONE, "Choose an option:", newGameButtonType, continueButtonType);
        alert.setTitle("Snake Game");
        alert.setHeaderText("Welcome to Snake Game!");
        alert.showAndWait();

        if (alert.getResult() == newGameButtonType) {
            newGame();
        } else {
            loadGame();
        }

        // 显示游戏界面
        Scene scene = new Scene(root);
        primaryStage.setScene(scene);
        primaryStage.setTitle("Snake Game");
        primaryStage.setResizable(false);
        primaryStage.show();

        // 启动游戏循环
        timer.start();
    }

    // 初始化贪吃蛇
    private void initSnake() {
        snake = new ArrayList<>();
        head = new Cell(WIDTH / 2, HEIGHT / 2);
        snake.add(head);
        for (int i = 1; i <= 3; i++) {
            snake.add(new Cell(head.getX() - i * CELL_SIZE, head.getY()));
        }
        createFood();
    }

    // 移动贪吃蛇
    private void moveSnake() {
        Cell tail = snake.remove(snake.size() - 1);
        tail.setX(head.getX() + direction.getX() * CELL_SIZE);
        tail.setY(head.getY() + direction.getY() * CELL_SIZE);
        snake.add(0, tail);
        head = tail;
    }

    // 绘制贪吃蛇
    private void drawSnake() {
        gc.clearRect(0, 0, WIDTH, HEIGHT);
        gc.setFill(Color.GREEN);
        for (Cell cell : snake) {
            gc.fillRect(cell.getX(), cell.getY(), CELL_SIZE, CELL_SIZE);
        }
        gc.setFill(Color.RED);
        gc.fillRect(food.getX(), food.getY(), CELL_SIZE, CELL_SIZE);
    }

    // 检查碰撞
    private void checkCollision() {
        if (head.getX() < 0 || head.getX() >= WIDTH || head.getY() < 0 || head.getY() >= HEIGHT) {
            gameOver = true;
        }
        for (int i = 1; i < snake.size(); i++) {
            if (head.getX() == snake.get(i).getX() && head.getY() == snake.get(i).getY()) {
                gameOver = true;
                break;
            }
        }
    }

    // 检查食物
    private void checkFood() {
        if (head.getX() == food.getX() && head.getY() == food.getY()) {
            snake.add(new Cell(food.getX(), food.getY()));
            createFood();
        }
    }

    // 创建食物
    private void createFood() {
        Random random = new Random();
        int x = random.nextInt(WIDTH / CELL_SIZE) * CELL_SIZE;
        int y = random.nextInt(HEIGHT / CELL_SIZE) * CELL_SIZE;
        for (Cell cell : snake) {
            if (cell.getX() == x && cell.getY() == y) {
                createFood();
                return;
            }
        }
        food = new Cell(x, y);
    }

    // 保存游戏
    private void saveGame() {
        try (ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream("snake.dat"))) {
            out.writeObject(snake);
            out.writeObject(head);
            out.writeObject(food);
            out.writeObject(direction);
            out.writeInt(highScore);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    // 加载游戏
    private void loadGame() {
        try (ObjectInputStream in = new ObjectInputStream(new FileInputStream("snake.dat"))) {
            snake = (List<Cell>) in.readObject();
            head = (Cell) in.readObject();
            food = (Cell) in.readObject();
            direction = (Direction) in.readObject();
            highScore = in.readInt();
        } catch (IOException | ClassNotFoundException e) {
            e.printStackTrace();
            newGame();
        }
    }

    // 新游戏
    private void newGame() {
        initSnake();
        highScore = 0;
        saveHighScore();
    }

    // 游戏结束
    private void gameOver() {
        if (snake.size() - 1 > highScore) {
            highScore = snake.size() - 1;
            saveHighScore();
        }
        Alert alert = new Alert(Alert.AlertType.INFORMATION);
        alert.setTitle("Game Over");
        alert.setHeaderText("Game Over");
        alert.setContentText("Your score is " + (snake.size() - 1));
        alert.showAndWait();
        newGame();
    }

    // 保存最高分
    private void saveHighScore() {
        try (PrintWriter out = new PrintWriter(new FileWriter("highscore.txt"))) {
            out.println(highScore);
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    // 加载最高分
    private void loadHighScore() {
        try (Scanner in = new Scanner(new FileInputStream("highscore.txt"))) {
            highScore = in.nextInt();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    // 格子
    private static class Cell implements Serializable {
        private int x;
        private int y;

        public Cell(int x, int y) {
            this.x = x;
            this.y = y;
        }

        public int getX() {
            return x;
        }

        public void setX(int x) {
            this.x = x;
        }

        public int getY() {
            return y;
        }

        public void setY(int y) {
            this.y = y;
        }
    }

    // 方向
    private enum Direction implements Serializable {
        UP(0, -1), DOWN(0, 1), LEFT(-1, 0), RIGHT(1, 0);

        private int x;
        private int y;

        Direction(int x, int y) {
            this.x = x;
            this.y = y;
        }

        public int getX() {
            return x;
        }

        public int getY() {
            return y;
        }
    }

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

}