6&7ShoppingCar.zip_6&7_jsp购物车mysql_mysql jsp 简单_mysql 实现集合_购物车my

package com.servlet; import java.io.IOException; import java.sql.Connection; import java.util.ArrayList; import java.util.List; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import javax.servlet.http.HttpSession; import com.bean.Good; import com.dao.Dao; import com.dao.GoodDao; @WebServlet("/GoodServlet") public class GoodServlet extends HttpServlet { private static final long serialVersionUID = 1L; private GoodDao goodDao=null; private List<Good> carList =null; protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { HttpSession session = request.getSession(); carList = (List<Good>) session.getAttribute("carList"); if(carList==null){ List<Good> list=new ArrayList<Good>(); session.setAttribute("carList", list); } //获取goodDao goodDao=(GoodDao) session.getAttribute("goodDao"); if(goodDao==null){ goodDao=new GoodDao(); session.setAttribute("goodDao", goodDao); } request.setCharacterEncoding("utf-8"); String method = request.getParameter("method"); if(method.equals("findAll")){ findAll(request,response); } if(method.equals("buy")){ buy(request,response); } if(method.equals("shopCar")){ shopCar(request,response); } if(method.equals("remove")){ remove(request,response); } if(method.equals("removeAll")){ removeAll(request,response); } } //向购物车中添加商品 protected void addShopCar(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { HttpSession session = request.getSession(); // List<Good> carList = (List<Good>) session.getAttribute("carList"); String id = request.getParameter("id"); Good good = goodDao.getOne(id); //购物车为空的时候 if(good!=null){ if(carList.size()==0){ Good temp=new Good(); temp.setName(good.getName()); System.out.println(good.getPrice()); temp.setNum(1); temp.setPrice(good.getPrice()); carList.add(temp); }else{ int i=0; //存在添加商品 for(;i<carList.size();i++){ Good temp=(Good) carList.get(i); if(temp.getName().equals(good.getName())){ temp.setNum(temp.getNum()+1); break; } } //不存在添加商品 if(i>=carList.size()){ Good temp=new Good(); temp.setName(good.getName()); temp.setNum(1); temp.setPrice(good.getPrice()); carList.add(temp); } } } } //读取数据库中所有图书信息 protected void findAll(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { List<Good> goodList = goodDao.getAllGood(); HttpSession session = request.getSession(); session.setAttribute("goodList", goodList); request.getRequestDispatcher("/WEB-INF/pages/list.jsp").forward(request, response); } //购买商品后，修改库存 protected void buy(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { HttpSession session = request.getSession(); Object obj = session.getAttribute("user"); //判断用户是否登录 if(obj==null){ request.getRequestDispatcher("login.jsp").forward(request, response); }else{ String id = request.getParameter("id"); String sql="update good set num=num-1 where id=?"; goodDao.update(id,sql); addShopCar(request,response); findAll(request,response); } } //跳转到购物车页面 protected void shopCar(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { request.getRequestDispatcher("/WEB-INF/pages/shopCar.jsp").forward(request, response); } //移出购物车中商品，修改数据库中的数据 protected void remove(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //修改数据库中的数据 String name = (String) request.getParameter("name"); System.out.println(name); String sql="update good set num=num+1 where name=?"; goodDao.update(name, sql); //修改Sessio中List的数据 HttpSession session = request.getSession(); List<Good> carList = (List<Good>) session.getAttribute("carList"); for(int i=0;i<carList.size();i++){ Good temp=(Good)carList.get(i); if(temp.getName().equals(name)){ if(temp.getNum()>1){ temp.setNum(temp.getNum()-1); break; }else if(temp.getNum()==1){ carList.remove(i); } } } request.getRequestDispatcher("/WEB-INF/pages/shopCar.jsp").forward(request, response); } //移出购物车中的所有商品 protected void removeAll(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //修改Sessio中List的数据 HttpSession session = request.getSession(); String sql=null; // List<Good> carList = (List<Good>) session.getAttribute("carList"); for(int i=0;i<carList.size();i++){ sql="update good set num=num+"+carList.get(i).getNum()+" where name=?"; goodDao.update(carList.get(i).getName(), sql); } session.removeAttribute("carList"); request.getRequestDispatcher("/WEB-INF/pages/shopCar.jsp").forward(request, response); } protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }