网上购物系统用SSH实现的

				package cn.com.tarena.ecport.biz.impl;
				
				import java.util.Iterator;
				
				import cn.com.tarena.ecport.biz.IShoppingCart;
				import cn.com.tarena.ecport.pojo.OrderLine;
				import cn.com.tarena.ecport.pojo.Orders;
				import cn.com.tarena.ecport.pojo.Product;
				
				public class ShoppingCartImpl implements IShoppingCart {
				
					private Orders order = new Orders();
					
					public void addProduct(Product product, int amount) {
				//		得到order中的所有orderLine比较与实参product的id是否相等，相等则在原有基础加上数量
						Iterator it = order.getOrderlines().iterator();
						while(it.hasNext()){
							OrderLine orderLine = (OrderLine)it.next();
							if(orderLine!=null&&product.getProductid()==orderLine.getProduct().getProductid()){
								orderLine.setAmount(orderLine.getAmount()+amount);
								return;
							}
						}
				//		执行到这里说明,没有匹配项。所以新增一条
						OrderLine orderLine = new OrderLine();
						orderLine.setAmount(amount);
						orderLine.setProduct(product);
						orderLine.setOrders(order);
						order.getOrderlines().add(orderLine);
						
					}
				
					public double getTotalPrice() {
						Iterator it = order.getOrderlines().iterator();
						double sum = 0;
						while(it.hasNext()){
							OrderLine orderLine = (OrderLine)it.next();
							sum = sum + orderLine.getProduct().getBaseprice()*orderLine.getAmount();
						}
						order.setCost(sum);
						return sum;
					}
				
					public void modifyProductAmountById(Long productid, int amount) {
				//		得到order中的所有orderLine比较与实参product的id是否相等，相等则在原有基础加上数量
						Iterator it = order.getOrderlines().iterator();
						while(it.hasNext()){
							OrderLine orderLine = (OrderLine)it.next();
							if(orderLine!=null&&productid==orderLine.getProduct().getProductid()){
								orderLine.setAmount(amount);
								return;
							}
						}
					}
				
					public void removeAllProducts() {
						order.getOrderlines().clear();
				
					}
				
					public void removeProductById(Long productid) {
						Iterator it = order.getOrderlines().iterator();
						OrderLine orderLine = null;
						while(it.hasNext()){
							orderLine = (OrderLine)it.next();
							if(orderLine!=null&&productid==orderLine.getProduct().getProductid()){
								break;
							}
						}
						if(orderLine!=null){
							order.getOrderlines().remove(orderLine);
						}
					}
				
					public Orders getOrder() {
						return order;
					}
					
				}