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;
}
}
原文地址：https://www.cnblogs.com/bichen-01/p/11676910.html
时间： 2024-10-13 00:41:59