用Struts做一个电子商务网站，不知道如何实现购物车，请各位大虾帮帮忙！！！
我的想法是在首页中实现将商品添加到购物车中，请问可以用什么方法实现？
------解决方案--------------------
------解决方案--------------------
1.session
2.建一个购物车的表
------解决方案--------------------
- Java code
<% String user_name = (String) session.getAttribute("user_name"); if (user_name == null) { out.println("<script>"); out.println("window.alert('你没有登陆，请先登录!');"); out.println("window.location=('user_login.jsp');"); out.println("</script>"); } //得到购物车信息 ArrayList orders_list = (ArrayList) session.getAttribute("orders_list"); if (orders_list == null || orders_list.size() == 0) { out.println("<script>"); out.println("window.alert('你的购物车为空');"); out.println("window.location=('product_group.jsp');"); out.println("</script>"); } else { SimpleDateFormat sdfDateTime = new SimpleDateFormat("yyyy-MM-dd:HH-mm-ss"); String dateTime = sdfDateTime.format(new Date()); out.print(dateTime); //得到当时时间信息 String order_name = user_name; //订单名称 order_name += ":"; order_name += dateTime; String product_names = ""; String order_counts = ""; String order_moneys = ""; int count = 0; //记录购买多少种商品 double order_money = 0; double total_money = 0; String order_datetime = dateTime; String list_datetime = dateTime; String result2 = null; String result3 = null; Iterator it = orders_list.iterator(); while (it.hasNext()) { OrderList shop = (OrderList) it.next(); if (user_name.equals(shop.getUserName())) { product_names += shop.getProductName() + ":"; order_counts += shop.getOrderCount() + ":"; count++; String product_name = shop.getProductName(); int order_count = shop.getOrderCount(); String list_name = user_name; list_name += ":"; list_name += product_name; double product_price = 0; String image_name = ""; String sql1 = "select product_price,image_name from products,images " + "where products.product_name like '%" + product_name.trim() + "%' and products.product_name = images.product_name"; database.setType(2); //访问数据库，提取商品相关的信息 database.setKeyword(sql1); StringBuffer b1 = database.byKeywordInquire(); String result1 = b1.toString(); StringTokenizer stkInfo = new StringTokenizer(result1, "#"); stkInfo.nextElement(); product_price = Double.parseDouble((String) stkInfo.nextElement()); image_name = (String) stkInfo.nextElement(); order_money = product_price*order_count; order_money = ((int)(order_money*100))/100; order_moneys += String.valueOf(order_money) + ":"; total_money = total_money + order_money; String sql2 = "insert into orderslist (list_name, user_name, product_name,product_price," +"order_count,order_money,image_name,order_name,list_datetime)" + " values('" + list_name + "','" + user_name + "','" + product_name + "'," + product_price + "," + order_count + "," + order_money + ",'" + image_name + "','" + order_name + "','" + list_datetime +"')"; database.setType(1); //访问数据库 database.setKeyword(sql2); StringBuffer b2 = database.byKeywordInquire(); result2 = b2.toString(); } } String sql3 = "insert into orders (order_name, user_name, product_names, total_money, order_datetime)" + " values('" + order_name + "','" + user_name + "','" + product_names + "'," + total_money +",'" + order_datetime + "')"; database.setType(1); //访问数据库 database.setKeyword(sql3); StringBuffer b3 = database.byKeywordInquire(); result3 = b3.toString(); if(result2.equals("success") && result3.equals("success")) { out.println("<script>"); out.println("window.alert('购物成功!感谢你购买我们的商品!');"); out.println("</script>"); } session.removeAttribute("orders_list"); String mailContent = null; mailContent = "<font color=blue><h2>感谢你购买我们的商品！</h2></font><br>" + "订单名称: " + order_name + "<br>" + "订单用户: " + user_name + "<br>" + "订单商品详细信息: <br><hr>"; mailContent += "<table width=400><tr>"; mailContent += "<td width='20%'>商品名</td>"; mailContent += "<td width='20%'>购买量</td>"; mailContent += "<td width='40%'>单个商品总价</td></tr>";%>