jsp統計在線人數代碼

　　首先寫個類:

    import javaxservlet*;

    import javaxservlet*;

    public class SessionCounter implements HttpSessionListener {

    private static int activeSessions = ;

    public void sessionCreated(HttpSessionEvent se) {

    activeSessions++;

    }

    public void sessionDestroyed(HttpSessionEvent se) {

    if(activeSessions > )

    activeSessions;

    }

    public static int getActiveSessions() {

    return activeSessions;

    }

    }

    然後配置webxml



    <?xml version="" encoding="UTF"?>

    <webapp version=""

    xmlns="

    xmlns:xsi="

    xsi:schemaLocation="



    ****************************************

    <! Listeners >

    <listener>

    <listenerclass>

    SessionCountSessionCounter (注意此處)

    </listenerclass>

    </listener>

    *****************************************

    </webapp>

  建個JSP測試:

    testjsp

    <%@ page language="Java" contentType="text/html;charset=GBK"%>

    <%@ page import="javasql*"%>

    <%@ page import="SessionCountSessionCounter" %>

    <html>

    <head>

    <meta httpequiv="ContentType" content="text/html; charset=GBK">

    <title>無標題文檔</title>

    <body bgcolor="#FFFFFF">

    在線人數:<%=SessionCountergetActiveSessions()%>

    </body>

    </html>

     測試以下會發現程序已經統計出結果了

From:http://tw.wingwit.com/Article/program/Java/Javascript/201311/25508.html