ajax struts购物车

package servlet.struts.action; import mybean.vo.*; import javax.servlet.http.*; import org.apache.struts.action.*; import org.apache.struts.actions.*; public class CartAction extends MappingDispatchAction { String xml=null; public ActionForward add(ActionMapping mapping,ActionForm form,HttpServletRequest req,HttpServletResponse resp) throws Exception { Cart cart = CartSession(req); String name=null;int price;String id=null; name=new String(req.getParameter("name").getBytes("ISO8859-1"),"GBK"); price=Integer.parseInt(req.getParameter("price")); id =req.getParameter("id"); cart.add(new Product(id,name,price,1)); this.Prt(req,resp); return null; } public ActionForward update(ActionMapping mapping,ActionForm form,HttpServletRequest req,HttpServletResponse resp) throws Exception { Cart cart= CartSession(req); int amount=Integer.parseInt(req.getParameter("amount")); int id = Integer.parseInt(req.getParameter("id")); cart.update(id,amount); this.Prt(req,resp); return null; } public ActionForward delete(ActionMapping mapping,ActionForm form, HttpServletRequest req, HttpServletResponse resp)throws Exception { Cart cart = CartSession(req); int id=Integer.parseInt(req.getParameter("id")); cart.delete(id); this.Prt(req,resp); return null; } public ActionForward removeAll(ActionMapping mapping,ActionForm form, HttpServletRequest req, HttpServletResponse resp)throws Exception { Cart cart = CartSession(req); cart.removeAll(); this.Prt(req,resp); return null; } private void Prt(HttpServletRequest req,HttpServletResponse resp) throws java.io.IOException { Cart cart = CartSession(req); xml=cart.toXML(); resp.setContentType("text/xml;charset=gb2312"); resp.getWriter().write(xml); } private Cart CartSession(HttpServletRequest req) { HttpSession session = req.getSession(); Cart cart = (Cart)session.getAttribute("cart"); if(cart == null) { cart = new Cart(); session.setAttribute("cart",cart); } return cart; } }