春节作业-小练习-购物车

春节作业-小练习-购物车

showServlet.java

package com.kd.servlet;

import java.io.IOException;
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 com.kd.entity.Goods;
import com.kd.service.GoodsService;
import com.kd.service.GoodsServiceImpl;


@WebServlet("/showServlet")
public class showServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
  
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		GoodsService goodsService=new GoodsServiceImpl();
		int pageNum=1;
		int pageSize=3;
		
		if(request.getParameter("pageNum")!=null) {
			pageNum=Integer.parseInt(request.getParameter("pageNum"));
		}
		try {
			List list=goodsService.getPaged(pageNum, pageSize);
			request.setAttribute("list", list);
			
			int count = goodsService.getCount();
			int num=count%pageSize ==0 ? count/pageSize : count/pageSize+1;
			request.setAttribute("num", num);
			
			request.setAttribute("currNum", pageNum);
			request.getRequestDispatcher("/WEB-INF/jsp/showGoods.jsp").forward(request, response);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		
		doGet(request, response);
	}

}

showGoods.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"  %>









商品信息浏览


		
	
	

		
编号
		
名称
		
价格
		
出厂日期
		
生产厂家
		
描述
		
操作
	
	

		

		
${goods.name}
		
${goods.price}
		
${goods.date}
		
${goods.company}
		
${goods.desc}
		
点击购买
		
	
	

		

			首页
			
			上一页
			
			
			上一页
			
			
				${pageNum}
			
			
			下一页
			
			
			下一页
			
			最后一页
			第页
		
	

shoppinServlet.java

package com.kd.servlet;

import java.io.IOException;
import java.util.HashMap;
import java.util.Map;

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 com.kd.entity.Goods;
import com.kd.service.GoodsService;
import com.kd.service.GoodsServiceImpl;



@WebServlet("/shoppingServlet")
public class shoppingServlet extends HttpServlet {
	private static final long serialVersionUID = 1L;
       
   
   
	protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
		request.setCharacterEncoding("utf-8");
		
		String id=request.getParameter("id");
		GoodsService goodsService=new GoodsServiceImpl();
			
		
		try {
			Goods goods=goodsService.getById(id);
			
			
			Map map =(Map)request.getSession().getAttribute("map");
	        //判断map是否为空
	        if(map == null) {//第一次购物
	            //创建购物车
	            map =new HashMap();
	            //把商品名称和数量放入到map中（购物车中）
	            map.put(goods, 1);
	        } else { //不是第一次购物
	            //判断是否有相同名称session
	            //第一种方式可以遍历
	            if(map.containsKey(goods)) {//有相同名称的key
	                //得到商品的数量，+1
	                int num = map.get(goods);
	                //把num+1，放到购物车
	                map.put(goods, num+1);
	            } else { //没有相同的key
	                //直接把商品名和数量1添加到购物车
	                map.put(goods, 1);
	            }
	        }
	        int count=0;
	        for ( Goods good : map.keySet()) {
				count+=map.get(good)*good.getPrice();
			}
	        request.setAttribute("count",count);
			request.getSession().setAttribute("map", map);
	        
			request.getRequestDispatcher("/WEB-INF/jsp/shopping.jsp").forward(request, response);
		} catch (Exception e) {
			e.printStackTrace();
		}
	}

	
	protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
			
		doGet(request, response);
	}

}

shopping.jsp

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"  %>









我的购物车


		
	
	

		
编号
		
名称
		
价格
		
数量
		
小计
	
	

		
${goods.key.id}
		
${goods.key.name}
		
${goods.key.price}
		
${map.get(goods.key)}
		
${map.get(goods.key)*goods.key.price}
		
	
	

	
总计:${count}
	
	

	
返回商品信息界面