Session详解,学习 Session对象一篇文章就够了

Session详解,学习 Session对象一篇文章就够了,第1张

目录

1 Session概述

2 Session原理

3 Session使用

3.1 获取Session

3.2 Session保存数据

3.3 Session获取数据

3.4 Session移除数据

4 Session与Request应用区别

4.1 Session和request存储数据

4.2 获取session和request中的值

4.3 session和request区别效果

5 Session的声明周期

5.1 Session有效时间设置

5.2 session销毁

.6 浏览器禁用Cookie解决方案(了解)

6.1 浏览器禁用Cookie的后果

6.2 URL重写

6.3 实现URL重写

7 Session实战权限验证

7.1 创建管理员表manager并添加数据

7.2 创建Web项目

7.3 基础环境搭建

7.4 登录页面

7.5 LoginMgrController

7.6 ShowAllManagerController

7.7 ShowAllManagerJsp

8 Session实战保存验证码

8.1 创建验证码

8.2 登录页面

8.3 LoginMgrController

8.4 ShowAllManagerController

今天的分享就到此结束了

创作不易点赞评论互关三连


1 Session概述

(1)Session用于记录用户的状态。Session指的是一段时间内,单个客户端与Web服务器的一连串相关的交互过程。

(2)在一个Session中,客户可能会多次请求访问同一个资源,也有可能请求访问各种不同的服务器资源。

(3)Session是由服务器端创建的

2 Session原理

(1)Session会为每一次会话分配一个Session对象

(2)同一个浏览器发起的多次请求,同属于一次会话(Session)

(3)首次使用到Session时,服务器会自动创建Session,并创建Cookie存储SessionId发送回客户端

3 Session使用

Session作用域:拥有存储数据的空间,作用范围是一次会话有效

  • 一次会话是使用同一浏览器发送的多次请求。一旦浏览器关闭,则结束会话

  • 可以将数据存入Session中,在一次会话的任意位置进行获取

  • 可传递任何数据(基本数据类型、对象、集合、数组)

3.1 获取Session

Session是服务器端自动创建的,通过request对象获取

package com.cxyzxc.www.servlet01;import javax.servlet.*; import javax.servlet.http.*; import javax.servlet.annotation.*; import java.io.IOException;@WebServlet(name = "SessionServlet01", value = "/SessionServlet01") public class SessionServlet01 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置请求参数的编码格式,这种方式对get请求方式无效 request.setCharacterEncoding("UTF-8"); //设置响应编码格式为UTF-8 response.setContentType("text/html;charset=UTF-8"); //获取Session对象,首次使用到Session时,服务器会自动创建Session,并创建Cookie存储SessionId发送回客户端 HttpSession session = request.getSession(); System.out.println("ID:" + session.getId());//唯一标记 } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

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3.2 Session保存数据

使用setArrtibute(属性名,Object)保存数据到session中

package com.cxyzxc.www.servlet01;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 = "SessionServlet02", value = "/SessionServlet02") public class SessionServlet02 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置请求参数的编码格式,这种方式对get请求方式无效 request.setCharacterEncoding("UTF-8"); //设置响应编码格式为UTF-8 response.setContentType("text/html;charset=UTF-8"); //获取Session对象,首次使用到Session时,服务器会自动创建Session,并创建Cookie存储SessionId发送回客户端 HttpSession session = request.getSession(); //将数据存储以键值对的形式到session对象中,可传递任何数据(基本数据类型、对象、集合、数组) session.setAttribute("username","张三"); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

 

3.3 Session获取数据

(1)使用getAttribute("属性名");获取session中数据。

(2)先访问SessionServlet02将数据存储到session对象中,然后通过GetSessionValueServlet01请求获取session中的数据

package com.cxyzxc.www.servlet01;import javax.servlet.*; import javax.servlet.http.*; import javax.servlet.annotation.*; import java.io.IOException;@WebServlet(name = "GetSessionValueServlet01", value = "/GetSessionValueServlet01") public class GetSessionValueServlet01 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置请求参数的编码格式,这种方式对get请求方式无效 request.setCharacterEncoding("UTF-8"); //设置响应编码格式为UTF-8 response.setContentType("text/html;charset=UTF-8"); //获取Session对象 HttpSession session = request.getSession(); //获取session对象中的值,获取的值是Object类型,转换为其对应的类型 String username = (String) session.getAttribute("username"); System.out.println("session对象中存储的username值:" + username); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

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3.4 Session移除数据

(1)使用removeAttribute("属性名");从session中删除数据

(2)向请求SessionServlet02向session对象中存储数据,然后访问GetSessionValueServlet01可以获取session对象中的值,再访问SessionServlet03移除session对象中存储的数据,最后访问GetSessionValueServlet01获取session对象中的值为null

package com.cxyzxc.www.servlet01;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 = "SessionServlet03", value = "/SessionServlet03") public class SessionServlet03 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置请求参数的编码格式,这种方式对get请求方式无效 request.setCharacterEncoding("UTF-8"); //设置响应编码格式为UTF-8 response.setContentType("text/html;charset=UTF-8"); //获取Session对象,首次使用到Session时,服务器会自动创建Session,并创建Cookie存储SessionId发送回客户端 HttpSession session = request.getSession(); //通过键移除session作用域中的值 session.removeAttribute("username"); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

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4 Session与Request应用区别

(1)request是一次请求有效,请求改变,则request改变

(2)session是一次会话有效,浏览器改变,则session改变

4.1 Session和request存储数据

package com.cxyzxc.www.servlet01;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 = "SessionServlet04", value = "/SessionServlet04") public class SessionServlet04 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置请求参数的编码格式,这种方式对get请求方式无效 request.setCharacterEncoding("UTF-8"); //设置响应编码格式为UTF-8 response.setContentType("text/html;charset=UTF-8"); //获取Session对象 HttpSession session = request.getSession(); //使用session存储数据 session.setAttribute("username","zhangsan"); //使用request存储数据 request.setAttribute("password","123456"); //重定向 response.sendRedirect("/webProject10_war_exploded/GetSessionValueServlet01"); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

 

4.2 获取session和request中的值

package com.cxyzxc.www.servlet01;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 = "GetSessionValueServlet01", value = "/GetSessionValueServlet01") public class GetSessionAndRequestValueServlet01 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置请求参数的编码格式,这种方式对get请求方式无效 request.setCharacterEncoding("UTF-8"); //设置响应编码格式为UTF-8 response.setContentType("text/html;charset=UTF-8"); //获取Session对象 HttpSession session = request.getSession(); //获取session对象中的值,获取的值是Object类型,转换为其对应的类型 String username = (String) session.getAttribute("username"); //获取request对象中的值,获取的值是Object类型,转换为其对应的类型 String password = (String) request.getAttribute("password"); System.out.println("session对象中存储的username值:" + username); System.out.println("request对象中存储的password值:" + password); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

4.3 session和request区别效果

Session详解,学习 Session对象一篇文章就够了,第5张

5 Session的声明周期

  1. 开始

    第一次使用到Session的请求产生,则创建Session

  2. 结束

    • 浏览器关闭,则失效

    • Session超时,则失效

      session.setMaxInactiveInterval(seconds);//设置最大有效时间(单位:秒)

    • 手工销毁,则失效

      session.invalidate();//登录退出,销毁

5.1 Session有效时间设置

SessionServlet05类设置session有效期为20秒,先通过请求SessionServlet05类将session存储在,然后在20秒内第一次在GetSessionValueServlet02获取sessionID值,与SessionServlet05类中输出的id值一致,过20秒后在GetSessionValueServlet02类中输出的sessionID值不一致了

 

package com.cxyzxc.www.servlet01;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 = "SessionServlet05", value = "/SessionServlet05") public class SessionServlet05 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置请求参数的编码格式,这种方式对get请求方式无效 request.setCharacterEncoding("UTF-8"); //设置响应编码格式为UTF-8 response.setContentType("text/html;charset=UTF-8"); //获取Session对象,首次使用到Session时,服务器会自动创建Session,并创建Cookie存储SessionId发送回客户端 HttpSession session = request.getSession(); //设置session有效期,时间单位为秒 session.setMaxInactiveInterval(20); //输出sessionid值 System.out.println("SessionServlet05类中输出ID:"+session.getId()); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

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5.2 session销毁

先使用GetSessionValueServlet03类获取session的id值,然后使用GetSessionValueServlet04类获取session的id值,两个类获取的id值一致,在GetSessionValueServlet04类中输出id值后销毁了session,然后再在GetSessionValueServlet03类中获取id值,就不一致了,就是服务器新建的session对象了

5.2.1 GetSessionValueServlet03类

package com.cxyzxc.www.servlet01;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 = "GetSessionValueServlet03", value = "/GetSessionValueServlet03") public class GetSessionValueServlet03 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置请求参数的编码格式,这种方式对get请求方式无效 request.setCharacterEncoding("UTF-8"); //设置响应编码格式为UTF-8 response.setContentType("text/html;charset=UTF-8"); //获取Session对象 HttpSession session = request.getSession(); //输出sessionid值 System.out.println("GetSessionValueServlet03类中输出ID:"+session.getId()); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

 

5.2.2 GetSessionValueServlet04类

package com.cxyzxc.www.servlet01;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 = "GetSessionValueServlet04", value = "/GetSessionValueServlet04") public class GetSessionValueServlet04 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置请求参数的编码格式,这种方式对get请求方式无效 request.setCharacterEncoding("UTF-8"); //设置响应编码格式为UTF-8 response.setContentType("text/html;charset=UTF-8"); //获取Session对象 HttpSession session = request.getSession(); //输出sessionid值 System.out.println("GetSessionValueServlet04类中输出ID:"+session.getId()); //销毁session session.invalidate(); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

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.6 浏览器禁用Cookie解决方案(了解)

6.1 浏览器禁用Cookie的后果

服务器在默认情况下,会使用Cookie的方式将sessionID发送给浏览器,如果用户禁止Cookie,则sessionID不会被浏览器保存,此时,服务器可以使用URL重写这样的方式来发送sessionID

 Session详解,学习 Session对象一篇文章就够了,第8张

多次请求GetSessionValueServlet05类输出的session的id值都不相同,并且在网站的Cookie对象中没有session的id值存在

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6.2 URL重写

浏览器在访问服务器上的某个地址时,不再使用原来的那个地址,而是使用经过改写的地址(即在原来的地址后面加上了sessionID)

6.3 实现URL重写

response.encodeRedirectURL(String url)生成重写的URL

6.3.1 重写URL

package com.cxyzxc.www.servlet01;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 = "GetSessionValueServlet06", value = "/GetSessionValueServlet06") public class GetSessionValueServlet06 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置请求参数的编码格式,这种方式对get请求方式无效 request.setCharacterEncoding("UTF-8"); //设置响应编码格式为UTF-8 response.setContentType("text/html;charset=UTF-8"); //获取Session对象 HttpSession session = request.getSession(); //输出sessionid值 System.out.println("GetSessionValueServlet06类中输出ID:"+session.getId()); //重写URL追加session值 String newURL = response.encodeURL("/webProject10_war_exploded/GetSessionValueServlet07"); System.out.println("重写后的URL:"+newURL); //重定向 response.sendRedirect(newURL); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

 

6.3.1 获取session

package com.cxyzxc.www.servlet01;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 = "GetSessionValueServlet07", value = "/GetSessionValueServlet07") public class GetSessionValueServlet07 extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置请求参数的编码格式,这种方式对get请求方式无效 request.setCharacterEncoding("UTF-8"); //设置响应编码格式为UTF-8 response.setContentType("text/html;charset=UTF-8"); //获取Session对象 HttpSession session = request.getSession(); //输出sessionid值 System.out.println("GetSessionValueServlet07类中输出ID:"+session.getId()); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

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7 Session实战权限验证

Session详解,学习 Session对象一篇文章就够了,第11张 

7.1 创建管理员表manager并添加数据

Session详解,学习 Session对象一篇文章就够了,第12张 

7.2 创建Web项目

创建Web项目,导入相关jar包

  • commons-dbutils-1.7.jar

  • druid-1.1.5.jar

  • mysql-connector-java-5.1.25-bin.jar

  • servlet-api.jar

7.3 基础环境搭建

在项目下创建包目录结构如下

  • com.cxyzxc.www.controller包:调用业务逻辑Servlet

  • com.cxyzxc.www.dao包:数据访问层接口

  • com.cxyzxc.www.dao.impl包:数据访问层接口实现类

  • com.cxyzxc.www.entity包:实体类

  • com.cxyzxc.www.jsp包:打印显示页面Servlet

  • com.cxyzxc.www.service包:业务逻辑层接口

  • com.cxyzxc.www.service.impl包:业务逻辑层接口实现类

  • com.cxyzxc.www.utils包:工具类

  • database.properties:数据库连接及连接池配置文件

7.4 登录页面

7.4.1 login.html

<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>管理员登录页面</title> <link type="text/css" rel="stylesheet" href="css/login.css"/> </head> <body> <div> <form action="LoginMgrController" method="post"> <p> 账号:<input type="text" name="username"/> </p> <p> 密码:<input type="password" name="password"/> </p> <p> <input type="submit" value="登录"/> </p> </form> </div> </body> </html>

 

7.4.2 login.css

* { margin: 0; padding: 0; }div { width: 400px; background-color: #ccc; margin: 30px auto; padding-top: 30px; text-align: center; }p { margin-top: 10px; }input { outline: none; }

7.5 LoginMgrController

package com.cxyzxc.www.controller;import com.cxyzxc.www.entity.Manager; import com.cxyzxc.www.service.ManagerService; import com.cxyzxc.www.service.impl.ManagerServiceImpl;import javax.servlet.*; import javax.servlet.http.*; import javax.servlet.annotation.*; import java.io.IOException;@WebServlet(name = "LoginMgrController", value = "/LoginMgrController") public class LoginMgrController extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //1、处理乱码 request.setCharacterEncoding("UTF-8"); response.setContentType("text/html;charset=UTF-8"); //2、收参(获取客户端发送过来的请求数据) String username = request.getParameter("username"); String password = request.getParameter("password"); //3、调用业务方法 ManagerService managerService = new ManagerServiceImpl(); Manager manager = managerService.login(username, password); //4、处理结果,根据结果做不同的跳转 if (manager != null) {//manager不为null,说明账号和密码正确,登录成功 //将获取的账号和密码信息存储在session中 HttpSession session = request.getSession(); session.setAttribute("manager", manager); //跳转到显示所有管理员信息的Servlet response.sendRedirect("/managerProject01_war_exploded/ShowAllManagerController"); } else {//manager为null。说明账号或者密码错误,登录失败 response.sendRedirect("/managerProject01_war_exploded/login.html"); } } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

7.6 ShowAllManagerController

package com.cxyzxc.www.controller;import com.cxyzxc.www.entity.Manager; import com.cxyzxc.www.service.ManagerService; import com.cxyzxc.www.service.impl.ManagerServiceImpl;import javax.servlet.*; import javax.servlet.http.*; import javax.servlet.annotation.*; import java.io.IOException; import java.util.List;@WebServlet(name = "ShowAllManagerController", value = "/ShowAllManagerController") public class ShowAllManagerController extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //1、处理乱码 request.setCharacterEncoding("UTF-8"); response.setContentType("text/html;charset=UTF-8"); //通过HttpSession完成权限控制 HttpSession session =request.getSession(); //获取session中存储的值 Manager manager = (Manager)session.getAttribute("manager"); //判断获取的值 if(manager!=null){ //调用业务,只做业务,业务与显示分离 ManagerService managerService = new ManagerServiceImpl(); List<Manager> managers =managerService.showAllManager(); //将获取的数据存储在request作用域中 request.setAttribute("managers",managers); //转发,跳转到显示结果的Servlet request.getRequestDispatcher("/ShowAllManagerJsp").forward(request,response); }else{ //说明没有登录,要先去登录才能进行显示 response.sendRedirect("/managerProject01_war_exploded/login.html"); } } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

7.7 ShowAllManagerJsp

package com.cxyzxc.www.jsp;import com.cxyzxc.www.entity.Manager;import javax.servlet.*; import javax.servlet.http.*; import javax.servlet.annotation.*; import java.io.IOException; import java.io.PrintWriter; import java.util.List;@WebServlet(name = "ShowAllManagerJsp", value = "/ShowAllManagerJsp") public class ShowAllManagerJsp extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //1、处理乱码 request.setCharacterEncoding("UTF-8"); response.setContentType("text/html;charset=UTF-8"); //2、获取数据 List<Manager> managers = (List<Manager>) request.getAttribute("managers"); //获取输出流 PrintWriter printWriter = response.getWriter(); if (managers.size() != 0) { printWriter.println("<html>"); printWriter.println("<head>"); printWriter.println("<title>所有管理员</title>"); printWriter.println("<link type=\"text/css\" rel=\"stylesheet\" href=\"css/table.css\" />"); printWriter.println("</head>"); printWriter.println("<table border='1px' cellspacing='0'>"); printWriter.println("<tr>"); printWriter.println(" <th>序号</th>"); printWriter.println(" <th>账号</th>"); printWriter.println(" <th>密码</th>"); printWriter.println(" <th> *** 作</th>"); printWriter.println(" </tr>"); for (int i = 0; i < managers.size(); i++) { printWriter.println("<tr>"); printWriter.println("<td>" + (i + 1) + "</td>"); printWriter.println("<td>" + managers.get(i).getUsername() + "</td>"); printWriter.println("<td>" + managers.get(i).getPassword() + "</td>"); printWriter.println("<td><a href=\"#\">修改</a> <a href=\"#\">删除</a></td>"); printWriter.println("</tr>"); } printWriter.println("</table>"); printWriter.println("</html>"); } else { printWriter.println("<h2>数据库中没有数据查询</h2>"); } } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

8 Session实战保存验证码

生成验证码的方式有很多种,可以使用随机数的方式实现,也可以使用ValidateCode类来实现(需要导入ValidateCode.jar包)。在这里,我们学习使用ValidateCode类来生成验证码

8.1 创建验证码

package com.cxyzxc.www.controller;import cn.dsna.util.images.ValidateCode;import javax.servlet.*; import javax.servlet.http.*; import javax.servlet.annotation.*; import java.io.IOException;/** * 此Servlet的作用是生成验证码并将生成的验证码存储到session中、发送到页面中显示 */ @WebServlet(name = "VerificationServlet", value = "/VerificationServlet") public class VerificationServlet extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //设置验证码规格 ValidateCode validateCode = new ValidateCode(200, 20, 4, 10); //获取验证码 String code = validateCode.getCode(); //将验证码存储在session中 HttpSession session = request.getSession(); session.setAttribute("code",code); //将验证码输出到客户端 validateCode.write(response.getOutputStream()); } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

8.2 登录页面

<!DOCTYPE html> <html lang="en"> <head> <meta charset="UTF-8"> <title>管理员登录页面</title> <link type="text/css" rel="stylesheet" href="css/login.css"/> </head> <body> <div> <form action="LoginMgrController" method="post"> <p> 账号:<input type="text" name="username"/> </p> <p> 密码:<input type="password" name="password"/> </p> <p> 验证码:<input type="text" name="verification"/> <img src="/managerProject02_war_exploded/VerificationServlet" /> </p> <p> <input type="submit" value="登录"/> </p> </form> </div> </body> </html>

8.3 LoginMgrController

package com.cxyzxc.www.controller;import com.cxyzxc.www.entity.Manager; import com.cxyzxc.www.service.ManagerService; import com.cxyzxc.www.service.impl.ManagerServiceImpl;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 = "LoginMgrController", value = "/LoginMgrController") public class LoginMgrController extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //1、处理乱码 request.setCharacterEncoding("UTF-8"); response.setContentType("text/html;charset=UTF-8"); //2、收参(获取客户端发送过来的请求数据) String username = request.getParameter("username"); String password = request.getParameter("password"); String inputCodde = request.getParameter("verification"); //获取session中的验证码 HttpSession session = request.getSession(); String codes = (String) session.getAttribute("code"); if (!inputCodde.isEmpty() && inputCodde.equalsIgnoreCase(codes)) { //3、调用业务方法 ManagerService managerService = new ManagerServiceImpl(); Manager manager = managerService.login(username, password); //4、处理结果,根据结果做不同的跳转 if (manager != null) {//manager不为null,说明账号和密码正确,登录成功 //将获取的账号和密码信息存储在session中 HttpSession session2 = request.getSession(); session2.setAttribute("manager", manager); //跳转到显示所有管理员信息的Servlet response.sendRedirect("/managerProject02_war_exploded/ShowAllManagerController"); } else {//manager为null。说明账号或者密码错误,登录失败 response.sendRedirect("/managerProject02_war_exploded/login.html"); } } else {//验证码不对,重新登录 response.sendRedirect("/managerProject02_war_exploded/login.html"); } } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

8.4 ShowAllManagerController

package com.cxyzxc.www.controller;import com.cxyzxc.www.entity.Manager; import com.cxyzxc.www.service.ManagerService; import com.cxyzxc.www.service.impl.ManagerServiceImpl;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; import java.util.List;@WebServlet(name = "ShowAllManagerController", value = "/ShowAllManagerController") public class ShowAllManagerController extends HttpServlet { @Override protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { //通过HttpSession完成权限控制 HttpSession session =request.getSession(); //获取session中存储的值 Manager manager = (Manager)session.getAttribute("manager"); //判断获取的值 if(manager!=null){ //调用业务,只做业务,业务与显示分离 ManagerService managerService = new ManagerServiceImpl(); List<Manager> managers =managerService.showAllManager(); //将获取的数据存储在request作用域中 request.setAttribute("managers",managers); //转发,跳转到显示结果的Servlet request.getRequestDispatcher("/ShowAllManagerJsp").forward(request,response); }else{ //说明没有登录,要先去登录才能进行显示 response.sendRedirect("/managerProject02_war_exploded/login.html"); } } @Override protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { doGet(request, response); } }

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