JavaWeb 购物车项目

今天是基于我们所学的服务器存储端和三层架构来完善该项目，今天先完善一部分的功能。一.购物车项目思路1.登录先创建一个用户表，表中有id,name,pwd三个属性首。需要具备一个登录页面，一个处理登录数据的页面，在该页面进行判断，当该用户存在，我们跳转到商城，用户不存在回到登录界面。2.商城创建一张商品表当登录成功以后跳转到商城页面，商城有商品显示，商品数据来自于商品表中的数据。点击加入购物车，如果

客行.

13309人浏览 · 2022-04-14 11:41:51

客行. · 2022-04-14 11:41:51 发布

今天是基于我们所学的服务器存储端和三层架构来完善该项目，今天先完善一部分的功能。

一.购物车项目思路

1.登录

先创建一个用户表，表中有id,name,pwd三个属性首。
需要具备一个登录页面，一个处理登录数据的页面，在该页面进行判断，当该用户存在，我们跳转到商城，用户不存在回到登录界面。

2.商城

创建一张商品表
当登录成功以后跳转到商城页面，商城有商品显示，商品数据来自于商品表中的数据。
点击加入购物车，如果点击加入的商品在购物车中存在的话，只增加商品数量，而不会在显示一条该商品数据。
点击加入购物车时携带商品id跳转到处理购物车数据的页面，我们把购物车中的数据存在session中。

3.购物车

购物车今天我们只做从session中把数据拿出来，显示在页面上，可以把总价计算出来，其他功能在下一篇文章给大家讲解

二.项目的文件路径展示

biz : 存放业务逻辑层的接口
biz.impl : 存放业务逻辑层的实现类
dao : 存放数据访问层的接口
dao.impl : 存放数据访问层的实现

三.项目代码展示

1.ulit包下DBHeper类代码展示

作用:连接数据库oracle

package com.yjx.ulit;

import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;

import oracle.jdbc.driver.OracleDriver;

public class DBHeper {
  static {
	  try {
		  Class.forName("oracle.jdbc.driver.OracleDriver");
	} catch (Exception e) {
		  e.printStackTrace();
	}
	  
  }
  
  private static final String URL="jdbc:oracle:thin:@localhost:1521:orcl";
  
  public static Connection getCon() {
	  try {
	 return	DriverManager.getConnection(URL,"scott","zking123");
	} catch (Exception e) {
		e.printStackTrace();
	}
	  return null;
  }
  
  public static void getColes(Connection con,PreparedStatement ps,ResultSet rs) {
	  try {
		  if(con!=null&&!con.isClosed())con.close();
		  if(ps!=null)ps.close();
		  if(rs!=null)rs.close();
	} catch (Exception e) {
		 e.printStackTrace();
	} 
	  
  }
}

2.pojo包下方的实体类

user:用户实体类

package com.yjx.pojo;

public class User {
  private int id;
  private String name;
  private String pwd;
public int getId() {
	return id;
}
public void setId(int id) {
	this.id = id;
}
public String getName() {
	return name;
}
public void setName(String name) {
	this.name = name;
}
public String getPwd() {
	return pwd;
}
public void setPwd(String pwd) {
	this.pwd = pwd;
}
  
  
public User() {
	
}

public User(int id, String name, String pwd) {
	super();
	this.id = id;
	this.name = name;
	this.pwd = pwd;
}


@Override
public String toString() {
	return "User [id=" + id + ", name=" + name + ", pwd=" + pwd + "]";
}


}

shop：商品实体类

package com.yjx.pojo;

public class Shop {
   private int id;
   private String name;
   private Double price;
   private String text;
public int getId() {
	return id;
}
public void setId(int id) {
	this.id = id;
}
public String getName() {
	return name;
}
public void setName(String name) {
	this.name = name;
}
public Double getPrice() {
	return price;
}
public void setPrice(Double price) {
	this.price = price;
}
public String getText() {
	return text;
}
public void setText(String text) {
	this.text = text;
}

public Shop(int id, String name, Double price, String text) {
	super();
	this.id = id;
	this.name = name;
	this.price = price;
	this.text = text;
}
   
   public Shop() {
	
}
   
@Override
public String toString() {
	return "Shop [id=" + id + ", name=" + name + ", price=" + price + ", text=" + text + "]";
}
   
   
   
}

3.vo包下购物车的实体类

package com.yjx.vo;

public class Car {
	private Integer id;
	private String name;
    private Integer count;
    private Double sum;
	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 getCount() {
		return count;
	}
	public void setCount(Integer count) {
		this.count = count;
	}
	public Double getSum() {
		return sum;
	}
	public void setSum(Double sum) {
		this.sum = sum;
	}
	@Override
	public String toString() {
		return "Car [id=" + id + ", name=" + name + ", count=" + count + ", sum=" + sum + "]";
	}
	public Car(Integer id, String name, Integer count, Double sum) {
		super();
		this.id = id;
		this.name = name;
		this.count = count;
		this.sum = sum;
	}
	
    public Car() {
		// TODO Auto-generated constructor stub
	}
    
    
}

4.数据访问层

user的数据访问层: dao : 存放数据访问层的接口(IUserDao)
dao.impl : 存放数据访问层的实现类(UserDaoImpl)

dao : 存放数据访问层的接口(IUserDao)

package com.yjx.dao;

import java.util.List;

import com.yjx.pojo.Shop;
import com.yjx.pojo.User;

public interface IUserDao {
   //登录方法
   User login(User u);
 
}

dao.impl : 存放数据访问层的实现类(UserDaoImpl)

package com.yjx.dao.impl;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;

import com.yjx.dao.IUserDao;
import com.yjx.pojo.Shop;
import com.yjx.pojo.User;
import com.yjx.ulit.DBHeper;

public class UserDaoimpl implements IUserDao{
		
	private Connection con;
	private PreparedStatement ps;
	private ResultSet rs;
	
	/**
	 * 登录方法
	 */
  
	public User login(User u) {
		try {
			con=DBHeper.getCon();
			ps=con.prepareStatement("select * from shop_user where uname=?");
			ps.setString(1,u.getName());
			rs=ps.executeQuery();
			if(rs.next()) {
			User user=new User();
			user.setId(rs.getInt(1));
			user.setName(rs.getString(2));
			user.setPwd(rs.getString(3));
			return user;
			}
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			DBHeper.getColes(con, ps, rs);
		}
		return null;
	}

}

shop的数据访问层: dao : 存放数据访问层的接口(IShopDao)
dao.impl : 存放数据访问层的实现类(ShoprDaoImpl)

dao : 存放数据访问层的接口(IShopDao)

package com.yjx.dao;

import java.util.List;

import com.yjx.pojo.Shop;

public interface IShopDao {
   //查询数据库中商品表中的所有数据
	List<Shop> select();
	
	//根据id查询数据

	Shop selectId(int id);
}

dao.impl : 存放数据访问层的实现类(ShoprDaoImpl)

package com.yjx.dao.impl;

import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.List;

import com.yjx.dao.IShopDao;
import com.yjx.pojo.Shop;
import com.yjx.ulit.DBHeper;

public class ShopDaoImpl implements IShopDao {
   private Connection con;
   private PreparedStatement ps;
   private ResultSet rs;

	public List<Shop> select() {
	 List<Shop> list=new ArrayList();
	 try {
		con=DBHeper.getCon();
		ps=con.prepareStatement("select * from shop");
		rs=ps.executeQuery();
		while(rs.next()) {
			Shop s=new Shop();
			s.setId(rs.getInt(1));
			s.setName(rs.getString(2));
			s.setPrice(rs.getDouble(3));
			s.setText(rs.getString(4));
			list.add(s);
		}
	} catch (Exception e) {
		e.printStackTrace();
	}finally {
		DBHeper.getColes(con, ps, rs);
	}
		 
		return list;
	}
	
	@Override
		public Shop selectId(int id) {
	
		 try {
			con=DBHeper.getCon();
			ps=con.prepareStatement("select * from shop where sidd=?");
			ps.setInt(1, id);
			rs=ps.executeQuery();
			if(rs.next()) {
				Shop s=new Shop();
				s.setId(rs.getInt(1));
				s.setName(rs.getString(2));
				s.setPrice(rs.getDouble(3));
				s.setText(rs.getString(4));
				return s;
			}
		} catch (Exception e) {
			e.printStackTrace();
		}finally {
			DBHeper.getColes(con, ps, rs);
		}
			 
			return null;
		}
}

5.业务逻辑层

user业务逻辑层： biz : 存放业务逻辑层的接口（IUserBiz）

biz.impl : 存放业务逻辑层的实现类（UserBizImpl）

biz : 存放业务逻辑层的接口（IUserBiz）

package com.yjx.biz;

import com.yjx.pojo.User;

public interface IUserBiz {
	//登录方法
	  User login(User u);

}

biz.impl : 存放业务逻辑层的实现类（UserBizImpl）

package com.yjx.biz.impl;

import com.yjx.biz.IUserBiz;
import com.yjx.dao.IUserDao;
import com.yjx.dao.impl.UserDaoimpl;
import com.yjx.pojo.User;

public class UserBizImpl implements IUserBiz{
	
	IUserDao dao=new UserDaoimpl();
 /**
  * 登录方法
  */
public User login(User u) {
	User user=dao.login(u);
	//当用户不为空
	if(user!=null) {
	if(user.getPwd().equals(u.getPwd())) {
		return user;
	}
	}
	 return null;
}
}

shop业务逻辑层： biz : 存放业务逻辑层的接口（IShopBiz）

biz.impl : 存放业务逻辑层的实现类（ShopBizImpl）

biz : 存放业务逻辑层的接口（IShopBiz

package com.yjx.biz;

import java.util.List;

import com.yjx.pojo.Shop;

public  interface IShopBiz {
 
	//查询数据库中商品表中的所有数据
	List<Shop> select();
	
	//根据id查询数据
	Shop selectId(int id);
}

biz.impl : 存放业务逻辑层的实现类（ShopBizImpl）

package com.yjx.biz.impl;

import java.util.List;

import com.yjx.biz.IShopBiz;
import com.yjx.dao.IShopDao;
import com.yjx.dao.impl.ShopDaoImpl;
import com.yjx.pojo.Shop;

public class ShopBizImpl implements IShopBiz{
  
	 IShopDao dao=new ShopDaoImpl();
	 /*
	  *查询商品表的所有数据 
	  */
	 @Override
	public List<Shop> select() {
		List<Shop> list=dao.select();
		return list;
	}
	 /**
	  * 根据id查询数据
	  */
	
	public Shop selectId(int id) {
		Shop s=dao.selectId(id);
		return s;
	}
}

6.登录界面

<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<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;">欢迎光临胡阿玛超市</h3>
        <div class="form-group">
            <input name="username" type="text" class="form-control" placeholder="请输入您的用户名">
        </div>
        <div class="form-group">
            <input name="userpwd" 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>

7.处理登录数据页面

<%@page import="java.util.ArrayList"%>
<%@page import="com.yjx.pojo.Shop"%>
<%@page import="java.util.List"%>
<%@page import="com.yjx.pojo.User"%>
<%@page import="com.yjx.biz.impl.UserBizImpl"%>
<%@page import="com.yjx.biz.IUserBiz"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>

 <%
  //接收数据
   String name=request.getParameter("username");
   String pwd=request.getParameter("userpwd");
     //实例一个用户，得到一个用户
     User u=new User(1,name,pwd);
     
     IUserBiz userbiz=new UserBizImpl();
     //调用登录方法，得到一个用户
     User user=userbiz.login(u);
     
     //判断该用户是否存在
     if(user!=null){
    	 //将用户存入session中
    	 session.setAttribute("user",user);
    	 
    	 List<Shop> list=new ArrayList();
    	 //将购物车存入session中
    	 session.setAttribute("list",list);
    	 //跳转到首页
    	 response.sendRedirect("index.jsp");
     }else{
    	 //当用户为空不存在，回到登录界面
    	 response.sendRedirect("login.jsp");
     }
      
 %>

8.商城首页

<%@page import="com.yjx.vo.Car"%>
<%@page import="java.util.List"%>
<%@page import="com.yjx.pojo.Shop"%>

<%@page import="com.yjx.biz.impl.ShopBizImpl"%>
<%@page import="com.yjx.biz.IShopBiz"%>
<%@page import="com.yjx.pojo.User"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<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>

<%
 Object obj=session.getAttribute("user");
if(obj==null){
    response.sendRedirect("/login.jsp");
    return;
  }
%>
<body>
    <div class="jumbotron">
        <div class="container">
            <h1>欢迎光临胡阿玛SuperMarket</h1>
            <!-- 强转成一个用户，拿到用户名字 -->
            <p>尊贵的<%=((User)obj).getName()%></p>
            <a href="car.jsp">购物车</a>
        </div>
    </div>
    <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>
        <%
       
         IShopBiz shop=new ShopBizImpl();
       
         //获得一个集合
          List<Shop>list=shop.select();
         //遍历数据
          for(Shop s:list){
   %>
        <tr>
            <td><%=s.getId() %></td>
            <td><%=s.getName() %></td>
            <td><%=s.getPrice() %></td>
            <td><%=s.getText() %></td>
            <td>
                <div class="btn-group btn-group-xs">
                <!-- 当点击了加入购物车将数商品的id传过去 -->
                    <a class="btn btn-primary" href="${pageContext.request.contextPath}/doShop.jsp?id=<%=s.getId()%>">添加购物车</a>
                </div>
            </td>
        </tr>
        <%
          }
        %>
    </table>
</body></html>

9.购物车数据处理页面

<%@page import="com.yjx.vo.Car"%>
<%@page import="java.util.List"%>
<%@page import="com.yjx.biz.impl.ShopBizImpl"%>
<%@page import="com.yjx.biz.IShopBiz"%>
<%@page import="com.yjx.pojo.Shop"%>
<%@page import="com.yjx.dao.impl.ShopDaoImpl"%>
<%@page import="com.yjx.dao.IShopDao"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<%

  List<Car> list=(List<Car>)session.getAttribute("list");
   //接收到传过来的数据
   String str=request.getParameter("id");
   
   //判断当在首页点击加入购物车时，已经存在购物车中的商品，只在数量上面新增
   int id=-1;
   if(str!=null){
	   id=Integer.parseInt(str);
   }
    
   boolean f=true;
    //遍历集合
    for(Car c:list){
    	if(c.getId()==id){
    		//数量+1
    	  c.setCount(c.getCount()+1);
    	  //总价
    	  c.setSum(c.getSum()*c.getCount());
    	  f=false;
    	  break;
    	}
    }
   
    if(f){
   IShopBiz sbiz=new ShopBizImpl();
   Shop s=sbiz.selectId(id);
   
   //将数据加入购物车中
   Car car=new Car();
   //id
   car.setId(s.getId());
   car.setName(s.getName());
   car.setCount(1);
   //总价
   car.setSum(s.getPrice()*car.getCount());
   list.add(car);
   
    }
   //更新购物车
   session.setAttribute("list",list);
   //跳回首页
   response.sendRedirect("index.jsp");
      
%>

10.购物车页面

<%@page import="com.yjx.vo.Car"%>
<%@page import="java.util.List"%>
<%@page import="com.yjx.pojo.User"%>
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <title>购物车</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;
        }

        td,
        th {
            text-align: center;
        }

        input {
            text-align: center;
        }
        
    </style>
</head>

 <%
   Object obj=session.getAttribute("user");
 
 %>
<body>
    <div class="jumbotron">
        <div class="container">
            <h1>欢迎光临胡阿玛购物车🛒</h1>
            <p>尊贵的<%=((User)obj).getName()%></p>
        </div>
    </div>
     <a href="index.jsp" >商城</a>
    <table class="table">
        <tr>
            <th>商品序号</th>
            <th>商品名称</th>
            <th>商品个数</th>
            <th>商品总价</th>
            <th>操作</th>
        </tr>
        <%
         List<Car> list=(List<Car>)session.getAttribute("list");
         Double sum=0.00;
        //遍历
        for(Car c:list){
              sum+=c.getSum();
        %>
        <tr>
            <td style="line-height: 30.5px;"><%=c.getId()%></td>
            <td style="line-height: 30.5px;"><%=c.getName() %></td>
            <td>
                <div class="input-group" style="width: 120px;margin: auto;">
                    <span class="input-group-btn">
                        <a class="btn btn-default" type="button" href="doCar.jsp?math=1&id=<%=c.getId()%>">-</a>
                    </span>
                    <input value="<%=c.getCount()%>" type="text" class="form-control">
                    <span class="input-group-btn">
                        <a class="btn btn-default" type="button" href="doCar.jsp?math=2&id=<%=c.getId()%>">+</a>
                    </span>
                </div>
            </td>
            <td style="line-height: 30.5px;">$<%=c.getSum() %></td>
            <td style="line-height: 30.5px;">
                <button class="btn btn-primary">删除</button>
            </td>
        </tr>
       <%
        }
       %>
    </table>

    <h1 class="alert alert-info">
        当前购物车总价
        <small><%=sum %></small>
        <button class="btn btn-danger">点我结算</button>
    </h1>
    
  
</body></html>

今天的学习就到这里啦，明天在给大家完善该购物车项目。