种设计模式网上订餐系统的代码Java

以下是一个简单的基于MVC设计模式的Java代码示例，用于网上订餐系统：

1. Model层 - Order.java

public class Order {
    private int orderId;
    private String customerName;
    private ArrayList<MenuItem> items;
    private double total;
    
    public Order(int orderId, String customerName) {
        this.orderId = orderId;
        this.customerName = customerName;
        items = new ArrayList<>();
        total = 0.0;
    }
    
    public int getOrderId() {
        return orderId;
    }

    public String getCustomerName() {
        return customerName;
    }

    public ArrayList<MenuItem> getItems() {
        return items;
    }

    public double getTotal() {
        return total;
    }
    
    public void addItem(MenuItem item) {
        items.add(item);
        total += item.getPrice();
    }
}

2. Model层 - MenuItem.java

public class MenuItem {
    private String name;
    private double price;
    
    public MenuItem(String name, double price) {
        this.name = name;
        this.price = price;
    }
    
    public String getName() {
        return name;
    }
    
    public double getPrice() {
        return price;
    }
}

3. View层 - OrderView.java

import java.util.ArrayList;
import java.util.Scanner;

public class OrderView {
    private Scanner scanner;
    
    public OrderView() {
        scanner = new Scanner(System.in);
    }
    
    public void displayMenu(ArrayList<MenuItem> menu) {
        System.out.println("Menu:");
        for (int i = 0; i < menu.size(); i++) {
            MenuItem item = menu.get(i);
            System.out.println(i + ". " + item.getName() + " - $" + item.getPrice());
        }
    }
    
    public int getMenuItemChoice() {
        System.out.print("Enter menu item number: ");
        return scanner.nextInt();
    }
    
    public String getCustomerName() {
        System.out.print("Enter customer name: ");
        scanner.nextLine();
        return scanner.nextLine();
    }
    
    public void displayOrder(Order order) {
        System.out.println("Order #" + order.getOrderId() + " for " + order.getCustomerName());
        System.out.println("Items:");
        for (MenuItem item : order.getItems()) {
            System.out.println("- " + item.getName() + " ($" + item.getPrice() + ")");
        }
        System.out.println("Total: $" + order.getTotal());
    }
}

4. Controller层 - OrderController.java

import java.util.ArrayList;

public class OrderController {
    private ArrayList<MenuItem> menu;
    private ArrayList<Order> orders;
    private OrderView view;
    
    public OrderController() {
        menu = new ArrayList<>();
        orders = new ArrayList<>();
        view = new OrderView();
        setupMenu();
    }
    
    private void setupMenu() {
        menu.add(new MenuItem("Hamburger", 5.99));
        menu.add(new MenuItem("Cheeseburger", 6.99));
        menu.add(new MenuItem("Hot Dog", 3.99));
        menu.add(new MenuItem("French Fries", 2.99));
    }
    
    public void start() {
        String customerName = view.getCustomerName();
        Order order = new Order(orders.size() + 1, customerName);
        int choice;
        do {
            view.displayMenu(menu);
            choice = view.getMenuItemChoice();
            if (choice >= 0 && choice < menu.size()) {
                MenuItem item = menu.get(choice);
                order.addItem(item);
            }
        } while (choice >= 0 && choice < menu.size());
        orders.add(order);
        view.displayOrder(order);
    }
}

5. Main函数 - Main.java

public class Main {
    public static void main(String[] args) {
        OrderController controller = new OrderController();
        controller.start();
    }
}

这个示例实现了基本的网上订餐系统，用户可以输入自己的名字并选择菜单中的项目，系统会生成一个订单并显示总价。这个系统可以通过添加更多的菜品和功能来进行扩展。