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有用时间设置
5.2 session销毁
.6 浏览器禁用Cookie解决方案(相识)
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 基础情况搭建
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
今天的分享就到此竣事了
创作不易点赞评论互关三连
1 Session概述
(1)Session用于记任命户的状态。Session指的是一段时间内,单个客户端与Web服务器的一连串相干的交互过程。
(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用
- 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,则竣事会话
- 可以将数据存入Session中,在一次会话的恣意位置进行获取
- 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);
- }
- }
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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是一次请求有用,请求改变,则request改变
(2)session是一次会话有用,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);
- }
- }
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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);
- }
- }
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5 Session的声明周期
- 开始
第一次使用到Session的请求产生,则创建Session
- 竣事
- 浏览器关闭,则失效
- Session超时,则失效
session.setMaxInactiveInterval(seconds);//设置最大有用时间(单位:秒)
- 手工销毁,则失效
session.invalidate();//登录退出,销毁
5.1 Session有用时间设置
SessionServlet05类设置session有用期为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值同等,过20秒后在GetSessionValueServlet02类中输出的sessionID值不同等了
- 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值同等,在GetSessionValueServlet04类中输出id值后销毁了session,然后再在GetSessionValueServlet03类中获取id值,就不同等了,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);
- }
- }
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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(相识)
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重写如许的方式来发送sessionID
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
6.2 URL重写
浏览器在访问服务器上的某个地址时,不再使用原来的谁人地址,而是使用颠末改写的地址(即在原来的地址背面加上了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);
- }
- }
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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
7.1 创建管理员表manager并添加数据
7.2 创建Web项目
创建Web项目,导入相干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 基础情况搭建
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:数据库毗连及毗连池设置文件
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>
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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;
- }
复制代码 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);
- }
- }
复制代码 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);
- }
- }
复制代码 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>操作</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);
- }
- }
复制代码 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);
- }
- }
复制代码 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>
复制代码 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);
- }
- }
复制代码 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);
- }
- }
复制代码 今天的分享就到此竣事了
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