JavaWeb購物車項目開發(fā)實戰(zhàn)指南
一、項目前提
1、購物車并不是一直放數(shù)據(jù)庫
2、選擇使用的技術:
session:(購物車項目使用session)
好處:快(放在內存當中),存對象的
壞處:占用內存,服務器意外待機數(shù)據(jù)會丟失cookie
好處:不占用內存,存儲很久
壞處:存在客戶端上,只能存String,數(shù)據(jù)有泄露的風險
二、數(shù)據(jù)庫的創(chuàng)建
用戶表
create table shop_user ( id number primary key,--用戶id account varchar2(30) not null,--用戶賬戶 password varchar2(30)not null--用戶密碼 );
商品表
create table shop_goods( id number primary key,--商品id name varchar2(50) not null,--商品名稱 price number default 0.0,--商品價格 info varchar2(255) default '三五產品' not null--商品介紹 );
三、eclipse進行創(chuàng)建包和類:

com.zking.util 幫助類com.zking.pojo 實體類com.zking.dao(放dao接口)com.zking.dao.imp (放dao接口實現(xiàn)類)com.zking.biz (業(yè)務邏輯層放dao方法)com.zking.biz.imp(業(yè)務邏輯層放dao實現(xiàn)類) com.zking.vo (view object 視圖對象 前端用)
四、主要實現(xiàn)功能
1、購物車用戶登錄
login.jsp
界面效果

代碼如下:
<%@ 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="${pageContext.request.contextPath}/bootstrap-3.3.7-dist/css/bootstrap.css" rel="external nofollow" rel="external nofollow" >
<script src="${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;">歡迎光臨苡桉超市</h3>
<div class="form-group">
<input name="account" type="text" class="form-control" placeholder="請輸入您的用戶名">
</div>
<div class="form-group">
<input name="password" type="password" class="form-control" placeholder="請輸入您的密碼">
</div>
<div class="btn-group">
<button type="submit" class="btn btn-primary">登錄</button>
<button type="button" class="btn btn-danger">沒有賬號?</button>
</div>
</form>
</body>
</html>doLogin.jsp(處理登錄界面)
<%@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{
//首頁需要登錄數(shù)據(jù)
session.setAttribute("user",user);
//分配購物車
List<CarItem>car=new ArrayList<>();
//放到session中(把購物車給我)
session.setAttribute("car", car);
response.sendRedirect("index.jsp");
}
%>用戶實體類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 (用戶邏輯接口)
package com.zking.biz;
import com.zking.pojo.User;
/**
* 用戶邏輯接口
* @author zjjt
*
*/
public interface IUserBiz {
User login(User user);
}UserBizImpl.java (用戶邏輯接口實現(xiàn)類)
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;
/**
* 用戶邏輯接口實現(xiàn)類
* @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(用戶數(shù)據(jù)訪問接口)
package com.zking.dao;
import com.zking.pojo.User;
/**
* 用戶數(shù)據(jù)訪問接口
* @author zjjt
*
*/
public interface IUserDao {
User login(User user);
}UserDaoImpl.java(用戶數(shù)據(jù)訪問接口實現(xiàn)類)
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、商品顯示
實現(xiàn)效果如下:
將數(shù)據(jù)庫存放的數(shù)據(jù)顯示在頁面上,尊貴的xxx通過session拿到登錄的用戶名

Goods.java(商品實體類)
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(首頁代碼)
<%@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="${pageContext.request.contextPath}/bootstrap-3.3.7-dist/css/bootstrap.css" rel="external nofollow" rel="external nofollow" >
<script src="${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>歡迎光臨苡桉SuperMarket</h1>
<p>尊貴的<%=((User)obj).getAccount() %></p>
</div>
</div>
<%=session.getAttribute("car")%>
<div class="container">
<table class="table">
<tr>
<th>商品序號</th>
<th>商品名稱</th>
<th>商品單價</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() %>" rel="external nofollow" class="btn btn-primary">添加購物車</a>
</div>
</td>
</tr>
<%
}
%>
</table>
</div>
</body>
</html>IGoodsBiz.java (商品邏輯接口)
package com.zking.biz;
import java.util.List;
import com.zking.pojo.Goods;
/**
* 商品邏輯接口
* @author zjjt
*
*/
public interface IGoodsBiz {
List<Goods>getAll();
//查詢單個
Goods getOne(Integer id);
}GoodsBizImpl.java (商品邏輯接口實現(xiàn)類)
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;
/**
* 商品邏輯接口實現(xiàn)類
* @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 (商品數(shù)據(jù)訪問接口)
package com.zking.dao;
import java.util.List;
import com.zking.pojo.Goods;
/**
* 商品數(shù)據(jù)訪問接口
* @author zjjt
*
*/
public interface IGoodsDao {
//查詢所有
List<Goods>getAll();
//查詢單個
Goods getOne(Integer id);
}GoodsDaoImpl.java (商品數(shù)據(jù)訪問接口實現(xiàn)類)
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;
/**
* 訪問數(shù)據(jù)接口實現(xiàn)類
* @author zjjt
*
*/
public class GoodsDaoImpl implements IGoodsDao{
private Connection con;
private PreparedStatement ps;
private ResultSet rs;
/**
* 查詢全部商品
*/
@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;
}
/**
* 根據(jù)id查詢商品
*/
@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、購物車添加&商品總數(shù)和價格的計算
doAddCar.java(處理添加購物車的頁面)
<%@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"%>
<%
//添加購物車的頁面
//拿購物車
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 判斷該商品是否存在
boolean f=true;
for(CarItem item:car){
//item.getGoods().getId() 條目的商品id
if(id==item.getGoods().getId()){
//商品應該是已經被添加了[購物車中某個條目的商品id和你需要添加的商品id相同了]
item.setCount(item.getCount()+1);//數(shù)量+1
item.setSum(item.getCount()*item.getGoods().getPrice());
f=false;
break;
}
}
//只要判斷f是否發(fā)生了改變
if(f){
//2-2、生成一個CarItem[如果購物車沒有該商品]
CarItem carItem=new CarItem();
//設置對應的商品數(shù)據(jù)
carItem.setGoods(goodsBiz.getOne(id));
//數(shù)量
carItem.setCount(1);
//加車數(shù)量*商品單價
//carItem.getCount()商品加車的數(shù)量
//carItem.getGoods().getPrice() 商品的單價
carItem.setSum(carItem.getCount()*carItem.getGoods().getPrice());
//將購物條目carItem 綁定到購物車
car.add(carItem);
}
//更新購物車
session.setAttribute("car", car);
//跳回首頁
response.sendRedirect("index.jsp");
%>CarItem.java(購物車中的每一項,每一個條目)
package com.zking.vo;
import com.zking.pojo.Goods;
/**
* 購物車中的每一項,每一個條目
* @author zjjt
*
*/
public class CarItem {
private Integer count;//數(shù)量
private Integer sum;//條目總價
private Goods goods;//對應的商品
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 + "]";
}
}效果先簡單打印到頁面 之后會進行修改

今天的分享就到這里結束啦!!??
以上就是關于JavaWeb購物車項目的一些內容!!??
總結
到此這篇關于JavaWeb購物車項目開發(fā)的文章就介紹到這了,更多相關JavaWeb購物車項目內容請搜索腳本之家以前的文章或繼續(xù)瀏覽下面的相關文章希望大家以后多多支持腳本之家!
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