目录
一、项目前提
1、应用系统定制开发购物车并不是一直放数据库
2、应用系统定制开发选择使用的技术:
:(应用系统定制开发购物车项目使用session)
- 好处:快(应用系统定制开发放在内存当中),存对象的
- 坏处:占用内存,应用系统定制开发服务器意外待机数据会丢失
cookie
- 好处:不占用内存,存储很久
- 坏处:存在客户端上,只能存String,数据有泄露的风险
二、数据库的创建
用户表
- create table shop_user (
- id number primary key,--用户id
- account varchar2(30) not null,--用户账户
- password varchar2(30)not null--用户密码
- );
商品表
- create table shop_goods(
- id number primary key,--商品id
- name varchar2(50) not null,--商品名称
- price number default 0.0,--商品价格
- info varchar2(255) default '三五产品' not null--商品介绍
- );
三、eclipse进行创建包和类:
- com.zking.util 帮助类
- com.zking.pojo 实体类
- com.zking.dao(放dao接口)
- com.zking.dao.imp (放dao接口实现类)
- com.zking.biz (业务逻辑层放dao方法)
- com.zking.biz.imp(业务逻辑层放dao实现类)
- com.zking.vo (view object 视图对象 前端用)
四、主要实现功能
1、购物车用户登录
login.jsp
界面效果
代码如下:
- <%@ page language="java" contentType="text/html; charset=UTF-8"
- pageEncoding="UTF-8"%>
- <!DOCTYPE html>
- <html lang="zh">
- <head>
- <meta charset="UTF-8">
- <title>Document</title>
- <meta name="viewport" content="width=device-width, initial-scale=1">
- <link rel="stylesheet" href="${pageContext.request.contextPath}/bootstrap-3.3.7-dist/css/bootstrap.css">
- <script src="${pageContext.request.contextPath}/bootstrap-3.3.7-dist/js/jquery-3.5.1.js"></script>
- <script src="${pageContext.request.contextPath}/bootstrap-3.3.7-dist/js/bootstrap.js"></script>
- <style>
- * {
- outline: none !important;
- }
-
- html,
- body {
- background: #1abe9c;
- }
-
- form {
- width: 300px;
- background: #ebeff2;
- box-shadow: 0px 0px 50px rgba(0, 0, 0, .5);
- border-radius: 5px;
- padding: 20px;
- position: absolute;
- left: 50%;
- top: 50%;
- transform: translate(-50%, -50%);
- }
-
- .btn-group {
- width: 100%;
- }
-
- .btn-group button {
- width: 50%;
- }
- </style>
- </head>
-
- <body>
- <form action="doLogin.jsp" method="post">
- <h3 class="text-center" style="text-shadow: 2px 2px 1px #ed3f3f;">欢迎光临苡桉超市</h3>
- <div class="form-group">
- <input name="account" type="text" class="form-control" placeholder="请输入您的用户名">
- </div>
- <div class="form-group">
- <input name="password" type="password" class="form-control" placeholder="请输入您的密码">
- </div>
- <div class="btn-group">
- <button type="submit" class="btn btn-primary">登录</button>
- <button type="button" class="btn btn-danger">没有账号?</button>
- </div>
- </form>
- </body>
- </html>
-
doLogin.jsp(处理登录界面)
- <%@page import="com.zking.vo.CarItem"%>
- <%@page import="java.util.ArrayList"%>
- <%@page import="java.util.List"%>
- <%@page import="com.zking.pojo.User"%>
- <%@page import="com.zking.biz.impl.UserBizImpl"%>
- <%@page import="com.zking.biz.IUserBiz"%>
- <%@ page language="java" contentType="text/html; charset=UTF-8"
- pageEncoding="UTF-8"%>
- <%
-
- request.setCharacterEncoding("UTF-8");
- String account=request.getParameter("account");
- String password=request.getParameter("password");
-
- IUserBiz userBiz=new UserBizImpl();
- User user=userBiz.login(new User(0,account,password));
-
- if(user==null){
- response.sendRedirect("login.jsp");
- }else{
- //首页需要登录数据
- session.setAttribute("user",user);
- //分配购物车
- List<CarItem>car=new ArrayList<>();
- //放到session中(把购物车给我)
- session.setAttribute("car", car);
- response.sendRedirect("index.jsp");
-
- }
-
- %>
用户实体类User.java
- package com.zking.pojo;
-
- public class User {
- private Integer id;
- private String account;
- private String password;
- public Integer getId() {
- return id;
- }
- public void setId(Integer id) {
- this.id = id;
- }
- public String getAccount() {
- return account;
- }
- public void setAccount(String account) {
- this.account = account;
- }
- public String getPassword() {
- return password;
- }
- public void setPassword(String password) {
- this.password = password;
- }
- public User(Integer id, String account, String password) {
- super();
- this.id = id;
- this.account = account;
- this.password = password;
- }
- public User() {
- super();
- }
- @Override
- public String toString() {
- return "User [id=" + id + ", account=" + account + ", password=" + password + "]";
- }
-
-
-
-
- }
IUserBiz.java (用户逻辑接口)
- package com.zking.biz;
-
- import com.zking.pojo.User;
- /**
- * 用户逻辑接口
- * @author zjjt
- *
- */
- public interface IUserBiz {
- User login(User user);
- }
UserBizImpl.java (用户逻辑接口实现类)
- package com.zking.biz.impl;
-
- import com.zking.biz.IUserBiz;
- import com.zking.dao.IUserDao;
- import com.zking.dao.impl.UserDaoImpl;
- import com.zking.pojo.User;
- /**
- * 用户逻辑接口实现类
- * @author zjjt
- *
- */
- public class UserBizImpl implements IUserBiz{
-
- private IUserDao userDao=new UserDaoImpl();
-
- @Override
- public User login(User user) {
- User u = userDao.login(user);
- if(u!=null) {
- if(u.getPassword().equals(user.getPassword())) {
- return u;
- }
- }
- return null;
- }
- }
IUserDao.java(用户数据访问接口)
- package com.zking.dao;
-
- import com.zking.pojo.User;
- /**
- * 用户数据访问接口
- * @author zjjt
- *
- */
- public interface IUserDao {
-
- User login(User user);
-
- }
UserDaoImpl.java(用户数据访问接口实现类)
- package com.zking.dao.impl;
-
- import java.sql.Connection;
- import java.sql.PreparedStatement;
- import java.sql.ResultSet;
- import java.util.List;
-
- import com.zking.dao.IUserDao;
- import com.zking.pojo.User;
- import com.zking.util.DBHelper;
-
- public class UserDaoImpl implements IUserDao {
-
- private Connection con;
- private PreparedStatement ps;
- private ResultSet rs;
-
- @Override
- public User login(User user) {
- try {
- con=DBHelper.getCon();
- ps=con.prepareStatement("select * from shop_user where account=?");
- ps.setString(1,user.getAccount());
- rs=ps.executeQuery();
- if(rs.next()) {
- User u=new User();
- u.setId(rs.getInt(1));
- u.setAccount(rs.getString(2));
- u.setPassword(rs.getString(3));
- return u;
- }
- } catch (Exception e) {
- e.printStackTrace();
- }finally {
- DBHelper.close(con, ps, rs);
- }
- return null;
- }
- }
2、商品显示
实现效果如下:
将数据库存放的数据显示在页面上,尊贵的xxx通过session拿到登录的用户名
Goods.java(商品实体类)
- package com.zking.pojo;
-
- public class Goods {
- private Integer id;
- private String name;
- private Integer price;
- private String info;
- public Integer getId() {
- return id;
- }
- public void setId(Integer id) {
- this.id = id;
- }
- public String getName() {
- return name;
- }
- public void setName(String name) {
- this.name = name;
- }
- public Integer getPrice() {
- return price;
- }
- public void setPrice(Integer price) {
- this.price = price;
- }
- public String getInfo() {
- return info;
- }
- public void setInfo(String info) {
- this.info = info;
- }
- public Goods(Integer id, String name, Integer price, String info) {
- super();
- this.id = id;
- this.name = name;
- this.price = price;
- this.info = info;
- }
- public Goods() {
- super();
- }
- @Override
- public String toString() {
- return "Goods [id=" + id + ", name=" + name + ", price=" + price + ", info=" + info + "]";
- }
-
-
- }
index.jsp(首页代码)
- <%@page import="com.zking.pojo.Goods"%>
- <%@page import="com.zking.biz.impl.GoodsBizImpl"%>
- <%@page import="com.zking.biz.IGoodsBiz"%>
- <%@page import="com.zking.pojo.User"%>
- <%@ page language="java" contentType="text/html; charset=UTF-8"
- pageEncoding="UTF-8"%>
- <!DOCTYPE html>
- <html lang="zh">
- <head>
- <meta charset="UTF-8">
- <title>Document</title>
- <meta name="viewport" content="width=device-width, initial-scale=1">
- <link rel="stylesheet" href="${pageContext.request.contextPath}/bootstrap-3.3.7-dist/css/bootstrap.css">
- <script src="${pageContext.request.contextPath}/bootstrap-3.3.7-dist/js/jquery-3.5.1.js"></script>
- <script src="${pageContext.request.contextPath}/bootstrap-3.3.7-dist/js/bootstrap.js"></script>
- <style>
-
- td:nth-child(3)::before{
- content: "$";
- }
-
- </style>
- </head>
-
- <body>
- <%
- Object obj=session.getAttribute("user");
- if(obj==null){
- response.sendRedirect("login.jsp");
- return;
- }
- %>
- <div class="jumbotron">
- <div class="container">
- <h1>欢迎光临苡桉SuperMarket</h1>
- <p>尊贵的<%=((User)obj).getAccount() %></p>
- </div>
- </div>
- <%=session.getAttribute("car")%>
- <div class="container">
- <table class="table">
- <tr>
- <th>商品序号</th>
- <th>商品名称</th>
- <th>商品单价</th>
- <th>商品描述</th>
- <th>操作</th>
- </tr>
- <%
- IGoodsBiz goodsBiz=new GoodsBizImpl();
- for(Goods goods:goodsBiz.getAll()){
- %>
- <tr>
- <td><%=goods.getId() %></td>
- <td><%=goods.getName() %></td>
- <td><%=goods.getPrice() %></td>
- <td><%=goods.getInfo() %></td>
- <td>
- <div class="btn-group btn-group-xs">
- <a href="doAddCar.jsp?id=<%=goods.getId() %>" class="btn btn-primary">添加购物车</a>
- </div>
- </td>
- </tr>
- <%
- }
- %>
- </table>
- </div>
- </body>
- </html>
IGoodsBiz.java (商品逻辑接口)
- package com.zking.biz;
- import java.util.List;
- import com.zking.pojo.Goods;
- /**
- * 商品逻辑接口
- * @author zjjt
- *
- */
- public interface IGoodsBiz {
- List<Goods>getAll();
-
- //查询单个
- Goods getOne(Integer id);
-
- }
GoodsBizImpl.java (商品逻辑接口实现类)
- package com.zking.biz.impl;
-
- import java.util.List;
-
- import com.zking.biz.IGoodsBiz;
- import com.zking.dao.IGoodsDao;
- import com.zking.dao.impl.GoodsDaoImpl;
- import com.zking.pojo.Goods;
- /**
- * 商品逻辑接口实现类
- * @author zjjt
- *
- */
- public class GoodsBizImpl implements IGoodsBiz {
-
- private IGoodsDao goodsDao=new GoodsDaoImpl();
- @Override
- public List<Goods> getAll() {
- return goodsDao.getAll();
- }
-
- @Override
- public Goods getOne(Integer id) {
- return goodsDao.getOne(id);
- }
- }
IGoodsDao.java (商品数据访问接口)
- package com.zking.dao;
- import java.util.List;
- import com.zking.pojo.Goods;
- /**
- * 商品数据访问接口
- * @author zjjt
- *
- */
- public interface IGoodsDao {
-
- //查询所有
- List<Goods>getAll();
-
- //查询单个
- Goods getOne(Integer id);
- }
GoodsDaoImpl.java (商品数据访问接口实现类)
- package com.zking.dao.impl;
- import java.sql.Connection;
- import java.sql.PreparedStatement;
- import java.sql.ResultSet;
- import java.util.ArrayList;
- import java.util.List;
- import com.zking.dao.IGoodsDao;
- import com.zking.pojo.Goods;
- import com.zking.pojo.User;
- import com.zking.util.DBHelper;
- /**
- * 访问数据接口实现类
- * @author zjjt
- *
- */
- public class GoodsDaoImpl implements IGoodsDao{
- private Connection con;
- private PreparedStatement ps;
- private ResultSet rs;
-
- /**
- * 查询全部商品
- */
- @Override
- public List<Goods> getAll() {
- List<Goods>list=new ArrayList<Goods>();
- try {
- con=DBHelper.getCon();
- ps=con.prepareStatement("select * from shop_goods ");
- rs=ps.executeQuery();
- while(rs.next()) {
- Goods goods=new Goods();
- goods.setId(rs.getInt(1));
- goods.setName(rs.getString(2));
- goods.setPrice(rs.getInt(3));
- goods.setInfo(rs.getString(4));
- list.add(goods);
- }
- return list;
- } catch (Exception e) {
- e.printStackTrace();
- }finally {
- DBHelper.close(con, ps, rs);
- }
- return list;
- }
-
- /**
- * 根据id查询商品
- */
- @Override
- public Goods getOne(Integer id) {
-
- try {
- con=DBHelper.getCon();
- ps=con.prepareStatement("select * from shop_goods where id=? ");
- ps.setInt(1, id);
- rs=ps.executeQuery();
- if(rs.next()) {
- Goods goods=new Goods();
- goods.setId(rs.getInt(1));
- goods.setName(rs.getString(2));
- goods.setPrice(rs.getInt(3));
- goods.setInfo(rs.getString(4));
- return goods;
- }
-
- } catch (Exception e) {
- e.printStackTrace();
- }finally {
- DBHelper.close(con, ps, rs);
- }
- return null;
- }
- }
3、购物车添加&商品总数和价格的计算
doAddCar.java(处理添加购物车的页面)
- <%@page import="java.util.List"%>
- <%@page import="com.zking.biz.impl.GoodsBizImpl"%>
- <%@page import="com.zking.biz.IGoodsBiz"%>
- <%@page import="com.zking.vo.CarItem"%>
- <%@ page language="java" contentType="text/html; charset=UTF-8"
- pageEncoding="UTF-8"%>
- <%
- //添加购物车的页面
-
- //拿购物车
- List<CarItem>car=(List<CarItem>)session.getAttribute("car");
-
- IGoodsBiz goodsBiz=new GoodsBizImpl();
-
-
- //1、得知道是那件商品
- String str=request.getParameter("id");
- int id=-1;
- if(str!=null){
- id=Integer.parseInt(str);
- }
-
- //2-1 判断该商品是否存在
- boolean f=true;
- for(CarItem item:car){
- //item.getGoods().getId() 条目的商品id
- if(id==item.getGoods().getId()){
- //商品应该是已经被添加了[购物车中某个条目的商品id和你需要添加的商品id相同了]
- item.setCount(item.getCount()+1);//数量+1
- item.setSum(item.getCount()*item.getGoods().getPrice());
- f=false;
- break;
- }
- }
- //只要判断f是否发生了改变
- if(f){
- //2-2、生成一个CarItem[如果购物车没有该商品]
- CarItem carItem=new CarItem();
-
- //设置对应的商品数据
- carItem.setGoods(goodsBiz.getOne(id));
- //数量
- carItem.setCount(1);
- //加车数量*商品单价
- //carItem.getCount()商品加车的数量
- //carItem.getGoods().getPrice() 商品的单价
- carItem.setSum(carItem.getCount()*carItem.getGoods().getPrice());
- //将购物条目carItem 绑定到购物车
- car.add(carItem);
-
- }
- //更新购物车
- session.setAttribute("car", car);
- //跳回首页
- response.sendRedirect("index.jsp");
- %>
CarItem.java(购物车中的每一项,每一个条目)
- package com.zking.vo;
-
- import com.zking.pojo.Goods;
-
- /**
- * 购物车中的每一项,每一个条目
- * @author zjjt
- *
- */
- public class CarItem {
-
- private Integer count;//数量
- private Integer sum;//条目总价
- private Goods goods;//对应的商品
- public Integer getCount() {
- return count;
- }
- public void setCount(Integer count) {
- this.count = count;
- }
- public Integer getSum() {
- return sum;
- }
- public void setSum(Integer sum) {
- this.sum = sum;
- }
- public Goods getGoods() {
- return goods;
- }
- public void setGoods(Goods goods) {
- this.goods = goods;
- }
- public CarItem(Integer count, Integer sum, Goods goods) {
- super();
- this.count = count;
- this.sum = sum;
- this.goods = goods;
- }
-
- public CarItem() {
- // TODO Auto-generated constructor stub
- }
- @Override
- public String toString() {
- return "CarItem [count=" + count + ", sum=" + sum + ", goods=" + goods + "]";
- }
-
-
- }
效果先简单打印到页面 之后会进行修改
今天的分享就到这里结束啦!!😊
以上就是关于JavaWeb购物车项目的一些内容!!📚