cart.java

网上购物系统struts+spring+hibernate实现

package com.sdi0708.bdifn.bookstore.domain;

import java.util.Collection;
import java.util.Collections;
import java.util.HashMap;
import java.util.Map;

public class Cart {
	@SuppressWarnings("unchecked")
	private final Map items = Collections
			.synchronizedMap(new HashMap());

	/**
	 * check the cart is that empty
	 * @return
	 */
	public boolean isEmpty() {
		return items.isEmpty();
	}
	/**
	 * clear the cart
	 */
	public void clear() {
//			for(Object key : items.keySet()) {
//				items.remove(key);
//			}
		items.clear();
	}
	/**
	 * add prudoct to a cart
	 * @param product
	 */
	@SuppressWarnings("unchecked")
	public void addItem(Product product) {
		Long id = product.getId();
		OrderItem item = (OrderItem) items.get(id);

		if(item == null) {
			item = new OrderItem();
			item.setProduct(product);
			item.setQuntity(0);
			item.setStatus(OrderItem.NEW);
		}
		item.incrementQauntity();
		
		this.items.put(id, item);
	}
	
	/**
	 * remove an orderItem from a cart
	 * @param id
	 * @return
	 */
	public OrderItem removeItemtByProductId(Long id) {
		OrderItem item = (OrderItem) items.remove(id);
		return item;
	}
	/**
	 * remove some orderItems from a cart
	 * @param ids
	 */
	public void removeItemsByProductId(Long[] ids) {
		for(Long id : ids) {
			items.remove(id);
		}
	}
	
	/**
	 * increment an item
	 */
	public void incrementQuntityById(Long ItemId) {
		OrderItem item = (OrderItem) items.get(ItemId);
		if(item != null){
			item.incrementQauntity();
		}
	}
	/**
	 * change the quntity by id.
	 * @param ItemId
	 * @param amount
	 */
	public void changeQuntity(Long ItemId, int amount) {
		OrderItem item = (OrderItem) items.get(ItemId);
		if(item != null) {
			item.setQuntity(amount);
		}
	}
	/**
	 * get the items from the cart
	 * @return
	 */
	@SuppressWarnings("unchecked")
	public Collection<OrderItem> getCartItems() {
		return items.values();
	}
	/**
	 * get the total price of the cartitems.
	 * @return
	 */
	public double getTotalPrice() {
		double totalPrice = 0;
		for(OrderItem item : getCartItems() ) {
			totalPrice = totalPrice + item.getCost() ;
		}
		return totalPrice;
	}
}