监听器(测试在线人数的)第一种 HttpSessionBindingListener
发布时间:2020-12-15 07:23:58 所属栏目:Java 来源:网络整理
导读:? index.jsp: % -- Created by IntelliJ IDEA. User: admin Date : 2019 / 10 / 15 Time : 11 : 52 To change this template use File | Settings | File Templates. -- % % @ page contentType = " text/html;charset=UTF-8 " language = " java " % html h
? index.jsp: <%-- Created by IntelliJ IDEA. User: admin Date: 2019/10/15 Time: 11:52 To change this template use File | Settings | File Templates. --%> <%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>HttpSessionBindingListener登录界面</title> </head> <body> <form action="doLogin.jsp"method="post"> <table align="center"> <tr><td> 账号姓名: <input type="text"name="userName"placeholder="请输入账号名"> <input type="submit"value="登录"> </td></tr> </table> </form> </body> </html> ? doLogin.jsp: <%@ page import="pojo.User" %><%-- Created by IntelliJ IDEA. User: admin Date: 2019/10/15 Time: 11:54 To change this template use File | Settings | File Templates. --%> <%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>HttpSessionBindingListener验证</title> </head> <body> <% String userName = request.getParameter("userName"); if(userName==null||userName.equals("")){ response.sendRedirect("index.jsp"); }else{ //登录成功! User user = new User(); user.setUserName(userName); session.setAttribute("user",user); response.sendRedirect("onLine.jsp"); } %> </body> </html> onLine.jsp: <%@ page import="pojo.User" %> <%@ page import="constants.Constants" %><%-- Created by IntelliJ IDEA. User: admin Date: 2019/10/15 Time: 11:57 To change this template use File | Settings | File Templates. --%> <%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>在线人数</title> </head> <body> <% User user = null; if(session.getAttribute("user")==null){ response.sendRedirect("index.jsp"); }else{ user = (User)session.getAttribute("user"); %> 欢迎您: <%=user.getUserName()%> 当前在线人数: <%=Constants.USER_COUNT%> <a href="loginOut.jsp">注销</a> <% } %> </body> </html> ? loginOut.jsp: <%-- Created by IntelliJ IDEA. User: admin Date: 2019/10/15 Time: 12:00 To change this template use File | Settings | File Templates. --%> <%@ page contentType="text/html;charset=UTF-8" language="java" %> <html> <head> <title>注销</title> </head> <body> <% session.invalidate(); response.sendRedirect("index.jsp"); %> </body> </html> javaBean: Constants类: package constants; public class Constants { public static int USER_COUNT = 0; } User类: package pojo; import constants.Constants; import javax.servlet.http.HttpSessionBindingEvent; import javax.servlet.http.HttpSessionBindingListener; public class User implements HttpSessionBindingListener { private String userName; private String password; public void valueBound(HttpSessionBindingEvent httpSessionBindingEvent) { Constants.USER_COUNT++; } public void valueUnbound(HttpSessionBindingEvent httpSessionBindingEvent) { Constants.USER_COUNT--; } public String getUserName() { return userName; } public void setUserName(String userName) { this.userName = userName; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } } (编辑:李大同) 【声明】本站内容均来自网络,其相关言论仅代表作者个人观点,不代表本站立场。若无意侵犯到您的权利,请及时与联系站长删除相关内容! |