目录
项目前提
数据库的创建
用户表
商品表
eclipse进行创建包和类：
主要实现功能
1、购物车用户登录
2、商品显示
3、购物车添加&商品总数和价格的计算
一、项目前提
1、购物车并不是一直放数据库
2、选择使用的技术：
session：（购物车项目使用session）
- 好处:快(放在内存当中)，存对象的
- 坏处:占用内存，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！！📚