创建java代码：大众4S店管理信息系统 汽车信息包括：汽车类别、汽车ID、汽车名字、汽车上市日期、购买价格、出售价格、颜色、厂商、发动机、车身结构（4门5座三厢车）。试用面向对象程序设计思想，设计一水禽管理管理信息系统，使之能提供以下功能： 1、汽车信息录入功能 2、汽车信息文件读取功能 3、汽车信息文件保存功能 4、汽车信息浏览功能 5、查询功能： 1）按汽车名字查询 2）按汽车类别查询 6、修改功能： 根据汽车ID修改相应信息； 7、删除汽车功能： 删除指定ID的汽车。 8、排序功能（由用户指定按照名称或ＩＤ；指定升序或降序） 9、退出

好的，以下是一个简单的大众4S店管理信息系统的Java代码示例：

Car.java

public class Car {
    private String category;
    private String id;
    private String name;
    private String launchDate;
    private double purchasePrice;
    private double sellingPrice;
    private String color;
    private String manufacturer;
    private String engine;
    private String bodyStructure;

    public Car(String category, String id, String name, String launchDate, double purchasePrice, double sellingPrice, String color, String manufacturer, String engine, String bodyStructure) {
        this.category = category;
        this.id = id;
        this.name = name;
        this.launchDate = launchDate;
        this.purchasePrice = purchasePrice;
        this.sellingPrice = sellingPrice;
        this.color = color;
        this.manufacturer = manufacturer;
        this.engine = engine;
        this.bodyStructure = bodyStructure;
    }

    // Getters and setters
    public String getCategory() {
        return category;
    }

    public void setCategory(String category) {
        this.category = category;
    }

    public String getId() {
        return id;
    }

    public void setId(String id) {
        this.id = id;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getLaunchDate() {
        return launchDate;
    }

    public void setLaunchDate(String launchDate) {
        this.launchDate = launchDate;
    }

    public double getPurchasePrice() {
        return purchasePrice;
    }

    public void setPurchasePrice(double purchasePrice) {
        this.purchasePrice = purchasePrice;
    }

    public double getSellingPrice() {
        return sellingPrice;
    }

    public void setSellingPrice(double sellingPrice) {
        this.sellingPrice = sellingPrice;
    }

    public String getColor() {
        return color;
    }

    public void setColor(String color) {
        this.color = color;
    }

    public String getManufacturer() {
        return manufacturer;
    }

    public void setManufacturer(String manufacturer) {
        this.manufacturer = manufacturer;
    }

    public String getEngine() {
        return engine;
    }

    public void setEngine(String engine) {
        this.engine = engine;
    }

    public String getBodyStructure() {
        return bodyStructure;
    }

    public void setBodyStructure(String bodyStructure) {
        this.bodyStructure = bodyStructure;
    }

    @Override
    public String toString() {
        return "Car{" +
                "category='" + category + '\'' +
                ", id='" + id + '\'' +
                ", name='" + name + '\'' +
                ", launchDate='" + launchDate + '\'' +
                ", purchasePrice=" + purchasePrice +
                ", sellingPrice=" + sellingPrice +
                ", color='" + color + '\'' +
                ", manufacturer='" + manufacturer + '\'' +
                ", engine='" + engine + '\'' +
                ", bodyStructure='" + bodyStructure + '\'' +
                '}';
    }
}

CarManagementSystem.java

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

public class CarManagementSystem {
    private List<Car> carList;

    public CarManagementSystem() {
        carList = new ArrayList<>();
    }

    // Add a new car
    public void addCar(Car car) {
        carList.add(car);
    }

    // Read car information from file
    public void readFromFile(String fileName) throws IOException {
        File file = new File(fileName);
        BufferedReader reader = new BufferedReader(new FileReader(file));
        String line;
        while ((line = reader.readLine()) != null) {
            String[] info = line.split(",");
            Car car = new Car(info[0], info[1], info[2], info[3], Double.parseDouble(info[4]), Double.parseDouble(info[5]), info[6], info[7], info[8], info[9]);
            carList.add(car);
        }
        reader.close();
    }

    // Save car information to file
    public void saveToFile(String fileName) throws IOException {
        File file = new File(fileName);
        BufferedWriter writer = new BufferedWriter(new FileWriter(file));
        for (Car car : carList) {
            writer.write(car.getCategory() + "," + car.getId() + "," + car.getName() + "," + car.getLaunchDate() + "," + car.getPurchasePrice() + "," + car.getSellingPrice() + "," + car.getColor() + "," + car.getManufacturer() + "," + car.getEngine() + "," + car.getBodyStructure());
            writer.newLine();
        }
        writer.close();
    }

    // Display all car information
    public void displayAllCars() {
        for (Car car : carList) {
            System.out.println(car);
        }
    }

    // Search car information by name
    public void searchCarByName(String name) {
        for (Car car : carList) {
            if (car.getName().equals(name)) {
                System.out.println(car);
            }
        }
    }

    // Search car information by category
    public void searchCarByCategory(String category) {
        for (Car car : carList) {
            if (car.getCategory().equals(category)) {
                System.out.println(car);
            }
        }
    }

    // Modify car information by id
    public void modifyCarById(String id, Car newCar) {
        for (int i = 0; i < carList.size(); i++) {
            if (carList.get(i).getId().equals(id)) {
                carList.set(i, newCar);
                return;
            }
        }
        System.out.println("Car with ID " + id + " not found.");
    }

    // Delete car by id
    public void deleteCarById(String id) {
        for (int i = 0; i < carList.size(); i++) {
            if (carList.get(i).getId().equals(id)) {
                carList.remove(i);
                return;
            }
        }
        System.out.println("Car with ID " + id + " not found.");
    }

    // Sort cars by name or id
    public void sortCars(boolean byName, boolean ascending) {
        Comparator<Car> comparator;
        if (byName) {
            comparator = Comparator.comparing(Car::getName);
        } else {
            comparator = Comparator.comparing(Car::getId);
        }
        if (!ascending) {
            comparator = comparator.reversed();
        }
        Collections.sort(carList, comparator);
    }

    public static void main(String[] args) throws IOException {
        Scanner scanner = new Scanner(System.in);
        CarManagementSystem system = new CarManagementSystem();

        boolean exit = false;
        while (!exit) {
            System.out.println("1. Add car");
            System.out.println("2. Read car information from file");
            System.out.println("3. Save car information to file");
            System.out.println("4. Display all cars");
            System.out.println("5. Search car by name");
            System.out.println("6. Search car by category");
            System.out.println("7. Modify car by ID");
            System.out.println("8. Delete car by ID");
            System.out.println("9. Sort cars");
            System.out.println("10. Exit");
            System.out.print("Enter your choice: ");
            int choice = scanner.nextInt();
            scanner.nextLine();

            switch (choice) {
                case 1:
                    System.out.print("Enter category: ");
                    String category = scanner.nextLine();
                    System.out.print("Enter ID: ");
                    String id = scanner.nextLine();
                    System.out.print("Enter name: ");
                    String name = scanner.nextLine();
                    System.out.print("Enter launch date: ");
                    String launchDate = scanner.nextLine();
                    System.out.print("Enter purchase price: ");
                    double purchasePrice = scanner.nextDouble();
                    System.out.print("Enter selling price: ");
                    double sellingPrice = scanner.nextDouble();
                    scanner.nextLine();
                    System.out.print("Enter color: ");
                    String color = scanner.nextLine();
                    System.out.print("Enter manufacturer: ");
                    String manufacturer = scanner.nextLine();
                    System.out.print("Enter engine: ");
                    String engine = scanner.nextLine();
                    System.out.print("Enter body structure: ");
                    String bodyStructure = scanner.nextLine();
                    Car newCar = new Car(category, id, name, launchDate, purchasePrice, sellingPrice, color, manufacturer, engine, bodyStructure);
                    system.addCar(newCar);
                    System.out.println("Car added successfully.");
                    break;
                case 2:
                    System.out.print("Enter file name: ");
                    String readFileName = scanner.nextLine();
                    system.readFromFile(readFileName);
                    System.out.println("Car information read successfully.");
                    break;
                case 3:
                    System.out.print("Enter file name: ");
                    String saveFileName = scanner.nextLine();
                    system.saveToFile(saveFileName);
                    System.out.println("Car information saved successfully.");
                    break;
                case 4:
                    system.displayAllCars();
                    break;
                case 5:
                    System.out.print("Enter car name: ");
                    String searchName = scanner.nextLine();
                    system.searchCarByName(searchName);
                    break;
                case 6:
                    System.out.print("Enter car category: ");
                    String searchCategory = scanner.nextLine();
                    system.searchCarByCategory(searchCategory);
                    break;
                case 7:
                    System.out.print("Enter car ID to modify: ");
                    String modifyId = scanner.nextLine();
                    System.out.print("Enter new category: ");
                    String modifyCategory = scanner.nextLine();
                    System.out.print("Enter new name: ");
                    String modifyName = scanner.nextLine();
                    System.out.print("Enter new launch date: ");
                    String modifyLaunchDate = scanner.nextLine();
                    System.out.print("Enter new purchase price: ");
                    double modifyPurchasePrice = scanner.nextDouble();
                    System.out.print("Enter new selling price: ");
                    double modifySellingPrice = scanner.nextDouble();
                    scanner.nextLine();
                    System.out.print("Enter new color: ");
                    String modifyColor = scanner.nextLine();
                    System.out.print("Enter new manufacturer: ");
                    String modifyManufacturer = scanner.nextLine();
                    System.out.print("Enter new engine: ");
                    String modifyEngine = scanner.nextLine();
                    System.out.print("Enter new body structure: ");
                    String modifyBodyStructure = scanner.nextLine();
                    Car modifiedCar = new Car(modifyCategory, modifyId, modifyName, modifyLaunchDate, modifyPurchasePrice, modifySellingPrice, modifyColor, modifyManufacturer, modifyEngine, modifyBodyStructure);
                    system.modifyCarById(modifyId, modifiedCar);
                    break;
                case 8:
                    System.out.print("Enter car ID to delete: ");
                    String deleteId = scanner.nextLine();
                    system.deleteCarById(deleteId);
                    break;
                case 9:
                    System.out.print("Sort by name or ID (N or I): ");
                    String sortChoice = scanner.nextLine();
                    boolean byName;
                    if (sortChoice.equalsIgnoreCase("N")) {
                        byName = true;
                    } else {
                        byName = false;
                    }
                    System.out.print("Sort in ascending or descending order (A or D): ");
                    sortChoice = scanner.nextLine();
                    boolean ascending;
                    if (sortChoice.equalsIgnoreCase("A")) {
                        ascending = true;
                    } else {
                        ascending = false;
                    }
                    system.sortCars(byName, ascending);
                    System.out.println("Cars sorted successfully.");
                    break;
                case 10:
                    exit = true;
                    break;
                default:
                    System.out.println("Invalid choice. Please try again.");
                    break;
            }
        }

        System.out.println("Goodbye!");
    }
}

请注意，这只是一个简单的示例，您可以根据自己的需求进行修改和扩展。此代码还需要添加异常处理和输入验证等功能以提高其健壮性。