电子商务系统二

import java.time.LocalDate;

import java.util.ArrayList;

import java.util.List;

public class Order {

private int orderId;

private User user;

private LocalDate orderDate;

private List<OrderItem> orderItems;

private double totalPrice;

private String shippingAddress;

public Order(User user, LocalDate orderDate, String shippingAddress) {

this.user = user;

this.orderDate = orderDate;

this.orderItems = new ArrayList<>();

this.shippingAddress = shippingAddress;

}

// 添加订单项

public void addOrderItem(Product product, int quantity) {

orderItems.add(new OrderItem(product, quantity));

calculateTotalPrice();

}

// 计算总价

private void calculateTotalPrice() {

totalPrice = orderItems.stream()

.mapToDouble(orderItem -> orderItem.getProduct().getPrice() * orderItem.getQuantity())

.sum();

}

// Getters and Setters

public int getOrderId() {

return orderId;

}

public void setOrderId(int orderId) {

this.orderId = orderId;

}

public User getUser() {

return user;

}

public LocalDate getOrderDate() {

return orderDate;

}

public List<OrderItem> getOrderItems() {

return orderItems;

}

public double getTotalPrice() {

return totalPrice;

}

public String getShippingAddress() {

return shippingAddress;

}

public void setShippingAddress(String shippingAddress) {

this.shippingAddress = shippingAddress;

}

// toString method

@Override 

public String toString() {

return "Order{" +

"orderId=" + orderId +

", user=" + user +

", orderDate=" + orderDate +

", orderItems=" + orderItems +

", totalPrice=" + totalPrice +

", shippingAddress='" + shippingAddress + '\'' +

'}';

}

// 订单项类

static class OrderItem {

private Product product;

private int quantity;

public OrderItem(Product product, int quantity) {

this.product = product;

this.quantity = quantity;

}

public Product getProduct() {

return product;

}

public int getQuantity() {

return quantity;

}

// toString method

@Override 

public String toString() {

return "OrderItem{" +

"product=" + product +

", quantity=" + quantity +

'}';

}

}

}

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

public class ECommerceSystem {

private Map<String, User> users; // 用户名和用户的映射

private List<Product> products; // 商品列表

private Map<Integer, Order> orders; // 订单ID和订单的映射

public ECommerceSystem() {

users = new HashMap<>();

products = new ArrayList<>();

orders = new HashMap<>();

}

// 注册新用户

public void registerUser(String username, String password, String email) {

User newUser = new User(username, password, email);

users.put(username, newUser);

}

// 用户登录

public User login(String username, String password) {

User user = users.get(username);

if (user != null && user.getPassword().equals(password)) {

return user;

}

return null;

}

// 浏览商品

public List<Product> browseProducts() {

return products;

}

// 添加到购物车

public ShoppingCart addToCart(User user, Product product, int quantity) {

ShoppingCart cart = new ShoppingCart();

cart.addItem(product, quantity);

// 在实际应用中，应该返回用户已有的购物车，或者将商品添加到用户现有的购物车中

return