关键是为每个bean建一个句柄，以后就可以引用，做购物车的时候可以用这个方法，也可以用到动态代理。

  if (cartHandle == null)

            {

                System.out.println("3");

                Context ctx = getInitialContext();

                Object obj = ctx.lookup("Cart");

                CartHome cartHome = (CartHome) javax.rmi.PortableRemoteObject.

                                    narrow(obj, CartHome.class);

                CustomerDto cusDto=null;

                cusDto=(CustomerDto)mysession.getAttribute("userDto");

                Cart cart = cartHome.create(cusDto);

                cartHandle = cart.getHandle();//得到有状态会话bean的HANDLE通过HANDLE来调用这个会话bean。

                cart.addItem(item);

                HttpSession session = servletRequest.getSession(true);

                session.setAttribute("cartHandle", cartHandle);

                //只创建一次，因为上面的HANDLE

               // saveToken(servletRequest);//利用同步令牌解决同步提交问题

                Map map = cart.getDetail();

                Collection collection = map.values();

                iterator = collection.iterator();

                list.clear();

                while (iterator.hasNext())

                {

                    ItemValue _item = (ItemValue) iterator.next();

                    list.add(_item);

                }

                double ret=cart.getTotal();

                mysession.setAttribute("totalPrice",new Double(ret));//在客户端调用

                mysession.setAttribute("shoppinglist", list);

            }