使用EJB创建Java企业级开发程序

				package shopcart.ejbs;								import java.io.*;								public class ShoppingCartItem 				implements Serializable				{					public String desc;					public double price;					public int quantity;					public int sales;										public ShoppingCartItem(String s,double p,int q)					{					    desc = s;					    price = p;					    quantity = q;					}										public double getTotal()					{					    return quantity*price;					}				}