利用Cookie和Session实现模拟购物车
利用Cookie实现模拟购物车
首先就是登陆界面：
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>logintitle>
head>
<body>
<center>
<form action="/helloWorld/login">
userName:<input type="text" name="userName"/><br/>
password: <input type="password" name="password"><br/>
<input type="submit" name="login" value="登录"><br/>
form>
center>
body>
html>
登录之后就是购买界面：
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>模拟购物车</title>
</head>
<body>
<center>
<!-- 模拟购物车页面 -->
java web程序设计<a href="/helloWorld/add?id=0">添加到购物车</a><br/>
Iphone Xr手机<a href="/helloWorld/add?id=1">添加到购物车</a><br/>
vivo X23手机幻彩版水滴屏 <a href="/helloWorld/add?id=2">添加到购物车</a><br/>
华为荣耀8X全面屏手机<a href="/helloWorld/add?id=3">添加到购物车</a><br/>
java SE基础教程<a href="/helloWorld/add?id=4">添加到购物车</a><br/>
<hr>
<a href="/helloWorld/show">查看购物车</a>
</center>
</body>
</html>
然后就是购买物品的功能Servlet:
package cn.njpji;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpSession;
import java.io.IOException;
public class addCarServlet extends javax.servlet.http.HttpServlet {
protected void doPost(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
doGet(request,response);
}
//实现模拟购物车功能
protected void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
response.setContentType("text/html;charset=utf-8");
//首先我们应该要获取客户端的JSESSIONID
HttpSession session = request.getSession(); //如果有的话，就不会再次创建新的JSESSIONID
/*我们都知道JSESSIONID也是一个cookie,而cookie每次在关闭浏览器就会被销毁对吧
* 所以我们现在应该让这个Session具有一定的持久化时间
* */
int count = 0;
Cookie cookie = new Cookie("JSESSIONID",session.getId());
cookie.setMaxAge(60);
response.addCookie(cookie); //将session作为新的cookie添加到浏览器
//拿到用户本次点击的商品标识id
String id = request.getParameter("id");
String value = null;
//定义一个商品数组
String[] products = {"java web程序设计","Iphone Xr手机","vivo X23手机幻彩版水滴屏","华为荣耀8X全面屏手机","java SE基础教程"};
Cookie[] cookies1 = request.getCookies(); //得到所有的cookie
if(cookies1!=null){
for(Cookie co:cookies1){
//对cookies1进行遍历，如果有名为改书籍的cookie就拿出来
if(co.getName().equals("product"+(Integer.parseInt(id)))){
value = co.getValue(); //这个值应该是书籍的数量
//判断拿出来的value是不是为空---不管他是不是空的，我都要给他加1个
count = Integer.parseInt(value)+1;
break;
}else{
count = 1; //因为第一次点击他是绝对不会存在的，所以...
}
}
//并且将新的值传回浏览器
Cookie cookie1 = new Cookie("product"+(Integer.parseInt(id)),""+count);
response.addCookie(cookie1);
response.sendRedirect("purchase.jsp");
}
}
}
然后就是显示购物车的Servlet:
package cn.njpji;
import javax.servlet.http.Cookie;
import java.io.IOException;
public class showCarServlet extends javax.servlet.http.HttpServlet {
protected void doPost(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
doGet(request,response);
}
protected void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
response.setContentType("text/html;charset=utf-8");
//展示购物车
//定义一个商品数组
String[] products = {"java web程序设计","Iphone Xr手机","vivo X23手机幻彩版水滴屏","华为荣耀8X全面屏手机","java SE基础教程"};
//得到所有的cookie
Cookie[] cookies = request.getCookies();
//对cookies进行遍历
if(cookies!=null){
response.getWriter().println("亲亲，您的购物车清单如下：
");
for(Cookie co:cookies){
for(int i=0;i<products.length;i++){
if(!co.getName().equals("product"+i)){
continue;
}else{
response.getWriter().println("商品："+products[i]+"\t 数量："+co.getValue()+"
");
}
}
}
}
}
}
肯定还有一个是登录的功能Servlet：
package cn.njpji;
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 javax.servlet.http.HttpSession;
import java.io.IOException;
@WebServlet(name = "loginServlet")
public class loginServlet extends HttpServlet {
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request,response);
}
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
response.setContentType("text/html;charset=utf-8");
//首先我们应该验证密码和用户是否正确
String name = request.getParameter("userName"); //得到用户输入的userName
String pwd = request.getParameter("password"); //得到用户输入的password
if((name.equals("cai")&&pwd.equals("123"))||(name.equals("zz")&&pwd.equals("123"))){
response.sendRedirect("purchase.jsp");
}else{
//如果密码错误，就会重定向到登陆界面
response.sendRedirect("index.jsp");
}
}
}
使用Session实现购物车功能
首先还是登陆界面：
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>logintitle>
head>
<body>
<center>
<form action="/helloWorld/login">
userName:<input type="text" name="userName"/><br/>
password: <input type="password" name="password"><br/>
<input type="submit" name="login" value="登录"><br/>
form>
center>
body>
html>
然后就是购买界面
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
<title>模拟购物车title>
head>
<body>
<center>
java web程序设计<a href="/helloWorld/add?id=0">添加到购物车a><br/>
Iphone Xr手机<a href="/helloWorld/add?id=1">添加到购物车a><br/>
vivo X23手机幻彩版水滴屏 <a href="/helloWorld/add?id=2">添加到购物车a><br/>
华为荣耀8X全面屏手机<a href="/helloWorld/add?id=3">添加到购物车a><br/>
java SE基础教程<a href="/helloWorld/add?id=4">添加到购物车a><br/>
<hr>
<a href="/helloWorld/show">查看购物车a>
center>
body>
html>
然后就是购买功能Servlet:
package cn.njpji;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;
public class addCarServlet extends javax.servlet.http.HttpServlet {
protected void doPost(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
doGet(request,response);
}
//实现模拟购物车功能
protected void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
response.setContentType("text/html;charset=utf-8");
//首先我们应该要获取客户端的JSESSIONID
HttpSession session = request.getSession(); //如果有的话，就不会再次创建新的JSESSIONID
/*我们都知道JSESSIONID也是一个cookie,而cookie每次在关闭浏览器就会被销毁对吧
* 所以我们现在应该让这个Session具有一定的持久化时间
* */
Cookie cookie = new Cookie("JSESSIONID",session.getId());
cookie.setMaxAge(60);
response.addCookie(cookie); //将session作为新的cookie添加到浏览器
//拿到用户本次点击的商品标识id
String id = request.getParameter("id");
//定义一个商品数组
String[] products = {"java web程序设计","Iphone Xr手机","vivo X23手机幻彩版水滴屏","华为荣耀8X全面屏手机","java SE基础教程"};
String productName = products[Integer.parseInt(id)]; //根据id拿到商品的name对吧
//然后我们还应该判断session有没有这个cart类集
Map<String,Integer> carMap = (Map<String, Integer>) session.getAttribute("cart"); //模拟购物车类集对象
if(carMap==null){
carMap = new HashMap<String, Integer>();
}
//首先我要查询这个carMap有没有要加入的商品
if(carMap.containsKey(productName)){
//如果存在就将value的值加1
carMap.put(productName,carMap.get(productName)+1);
}else{
carMap.put(productName,1);
}
session.setAttribute("cart",carMap); //将cart绑定这个session
// response.getWriter().println("添加购物车成功....");
response.sendRedirect("purchase.jsp");
}
}
然后就是显示购物车Servlet:
package cn.njpji;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpSession;
import java.io.IOException;
import java.util.Map;
import java.util.Set;
public class showCarServlet extends javax.servlet.http.HttpServlet {
protected void doPost(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
doGet(request,response);
}
protected void doGet(javax.servlet.http.HttpServletRequest request, javax.servlet.http.HttpServletResponse response) throws javax.servlet.ServletException, IOException {
response.setContentType("text/html;charset=utf-8");
//展示购物车
HttpSession session = request.getSession(); //得到当前的session对象
//得到session中存储的cart
Map<String,Integer> map = (Map<String, Integer>) session.getAttribute("cart");
if(map==null){
response.getWriter().println("亲亲，购物车空空如也呢...");
}else{
response.getWriter().println("购物清单如下：
");
//对map进行遍历
Set<String> stringSet = map.keySet();
for(String set:stringSet){
response.getWriter().println("商品："+set+"\t 数量:"+map.get(set)+"
");
}
}
}
}
然后还有什么？
哦，web.xml文件
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
version="4.0">
<servlet>
<servlet-name>addCarServletservlet-name>
<servlet-class>cn.njpji.addCarServletservlet-class>
servlet>
<servlet>
<servlet-name>showCarServletservlet-name>
<servlet-class>cn.njpji.showCarServletservlet-class>
servlet>
<servlet-mapping>
<servlet-name>showCarServletservlet-name>
<url-pattern>/showurl-pattern>
servlet-mapping>
<servlet-mapping>
<servlet-name>addCarServletservlet-name>
<url-pattern>/addurl-pattern>
servlet-mapping>
<session-config>
<session-timeout>0session-timeout>
session-config>
<servlet>
<servlet-name>LoginServletservlet-name>
<servlet-class>cn.njpji.loginServletservlet-class>
servlet>
<servlet-mapping>
<servlet-name>LoginServletservlet-name>
<url-pattern>/loginurl-pattern>
servlet-mapping>
web-app>
然后我们看看运行结果：
登录:
购买：
查询购物车:
