Java在线订单管理实现教程

public class Order {
    private String orderId;
    private String userId;
    private LocalDateTime orderDate;
    private double totalAmount;
    private String status; // 如：待支付、已发货、已完成
    private List items;
// 构造函数、getter和setter省略
}

public class OrderItem {
    private String productId;
    private String productName;
    private int quantity;
    private double price; // 单价
}

public class OrderService {
    private Map orderMap = new HashMap<>();
public void createOrder(Order order) {
    order.setOrderDate(LocalDateTime.now());
    order.setStatus("待支付");
    orderMap.put(order.getOrderId(), order);
}

public Order getOrder(String orderId) {
    return orderMap.get(orderId);
}

public void updateStatus(String orderId, String newStatus) {
    Order order = orderMap.get(orderId);
    if (order != null) {
        order.setStatus(newStatus);
    }
}

public List<Order> getOrdersByUser(String userId) {
    return orderMap.values().stream()
            .filter(o -> o.getUserId().equals(userId))
            .collect(Collectors.toList());
}
}

public Order buildOrder(String userId, List cartItems) {
    String orderId = "ORD" + System.currentTimeMillis();
    List items = new ArrayList<>();
    double total = 0.0;
for (CartItem item : cartItems) {
    OrderItem orderItem = new OrderItem();
    orderItem.setProductId(item.getProductId());
    orderItem.setProductName(item.getProductName());
    orderItem.setQuantity(item.getQuantity());
    orderItem.setPrice(item.getPrice());
    items.add(orderItem);
    total += item.getPrice() * item.getQuantity();
}

Order order = new Order();
order.setOrderId(orderId);
order.setUserId(userId);
order.setItems(items);
order.setTotalAmount(total);

return order;
}