First, write a class:
- Import javax. servlet .*;
- Import javax. servlet. http .*;
- Public class SessionCounter implements HttpSessionListener {
- Private static int activeSessions = 0;
- Public void sessionCreated (HttpSessionEvent se ){
- ActiveSessions;
- }
- Public void sessionDestroyed (HttpSessionEvent se ){
- If (activeSessions> 0)
- ActiveSessions --;
- }
- Public static int getActiveSessions (){
- Return activeSessions;
- }
- }
- Configure web. xml
- <? Xml version = "1.0" encoding = "UTF-8"?>
- <Web-app version = "2.4"
- Xmlns = "http://java.sun.com/xml/ns/j2ee"
- Xmlns: xsi = "http://www.w3.org/2001/XMLSchema-instance"
- Xsi: schemaLocation = "http://java.sun.com/xml/ns/j2ee
- Http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd>
- ****************************************
- <! -- Listeners -->
- <Listener>
- <Listener-class>
- SessionCount. SessionCounter (note here)
- </Listener-class>
- </Listener>
- **************************************** *
- </Web-app>
- Create a JSP test:
- Test. jsp
- <% @ Page language = "Java" contentType = "text/html; charset = GBK" %>
- <% @ Page import = "java. SQL. *" %>
- <% @ Page import = "SessionCount. SessionCounter" %>
- <Html>
- <Head>
- <Meta http-equiv = "Content-Type" content = "text/html; charset = GBK">
- <Title> untitled document </title>
- <Body bgcolor = "# FFFFFF">
- Online users: <% = SessionCounter. getActiveSessions () %>
- </Body>
- </Html>
Can it be implemented? I also found it. I used it and can make statistics.
