package com.ebook.servlet;import java.io.IOException;import javax.servlet.ServletException;import javax.servlet.http.HttpServlet;import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse;import javax.servlet.http.HttpSession;import com.ebook.Util.*;import java.util.*;import com.ebook.Entity.*;public class showCartServlet extends HttpServlet {    public void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {            HttpSession session = request.getSession();            shopCart cart = (shopCart) session.getAttribute("cart");            if (cart == null) {                request.setAttribute("error", "購物車中沒有任何物品");                     request.getRequestDispatcher("error.jsp").forward(request, response);                     return;            }                    // }         //    try {            ArrayList<cartItem> all = cart.getCart();            request.setAttribute("all", all);            String total=String.valueOf(cart.getTotal());            request.setAttribute("total", total);            request.getRequestDispatcher("showCart.jsp").forward(request, response);      //  } catch (Exception e) {       //       request.getRequestDispatcher("getError.jsp").forward(request, response);     //   }    }    public void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {        doGet(request, response);    }}