Yep, I do implement HttpSessionBindingListener and no I can't call
invalidate because I depend on other objects bound to the session within my
session tracker and invalidate does not define the order at which it will
unbind objects. Therefore I need to do an explicit removeAttribute call so
that I am assured the rest of the objects I need are still within the session.
For reference here is my code
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import edu.vt.ward.lexus.portal.User.*;
public class SessionTracker implements HttpSessionBindingListener{
private String userPid;
private ServletContext context;
private Hashtable currentSessions;
public SessionTracker (ServletContext ctx){
context = ctx;
}
public void valueBound(HttpSessionBindingEvent event) {
HttpSession session = event.getSession();
User user = (User) session.getAttribute("user");
userPid = user.getPid();
String totalLogins;
if(context.getAttribute("currentSessions") == null){
currentSessions = new Hashtable();
Date uptime = new Date(System.currentTimeMillis());
context.setAttribute("uptime", uptime);
totalLogins = "0";
}else{
currentSessions = (Hashtable)
context.getAttribute("currentSessions");
totalLogins = (String)
context.getAttribute("totalLogins");
}
Date creationTime = new Date(session.getCreationTime());
currentSessions.put(userPid, creationTime);
context.setAttribute("currentSessions", currentSessions);
int logins = Integer.parseInt(totalLogins) + 1;
totalLogins = Integer.toString(logins);
context.setAttribute("totalLogins", totalLogins);
}
public void valueUnbound(HttpSessionBindingEvent event) {
HttpSession session = event.getSession();
User user = (User) session.getAttribute("user");
userPid = user.getPid();
Hashtable currentSession = (Hashtable)
context.getAttribute("currentSessions");
currentSessions.remove(userPid);
context.setAttribute("currentSessions", currentSessions);
}
}
At 10:37 AM 4/10/2001, you wrote:
>Chad,
>
>I am doing something very similar...
>
>Are you implementing the HttpSessionBindingListener interface in your
>object? If not, try implementing this interface in your object that is
>placed in the session. This will throw a 'valueBound' event when the object
>is placed in the session and a 'valueUnbound' event when removed (either
>explicitly or by timeout). The valueBound method will increment the count,
>and the valueUnbound method will decrement it. Works perfectly for me.
>
>Also, you might want to use session.invalidate() rather than explicitly
>removing the session objects-- I found it was easier to manage.
>
>HTH,
>
>Mike
>
>
>
>
>-----Original Message-----
>From: Chad LaJoie [mailto:[EMAIL PROTECTED]]
>Sent: Tuesday, April 10, 2001 10:25 AM
>To: [EMAIL PROTECTED]
>Subject: Session timeouts
>
>
> I have been experiencing some problems with sessions timeouts. It
>seems that they are not unbinding all my sessions attributes. For
>instance. I have a session tracker object that gets bound to a user's
>session when they log in. This simply adds 1 to an application level
>attribute indicating the number of people who are currently logged
>in. When the user's logs out I call session.removeAttribute("tracker");
>explicitly and the attribute is unbound. This decrements the application
>attribute by 1. This all works fine. However if the session actually
>time's out the tracker object doesn't seem to be unbound. I.e. my little
>session tracker program still show the user as loged in.
> Has anyone else encountered this problem, and if so is there a
>solution for it?
>
>Env:
> Tomcat 3.2.1
> Sun JDK 1.3.0_1
> Apache 1.3.19
> Solaris 8
>
>Chad La Joie "Only a man who can not conquer
>IT Specialist his deficiencies feels the need to
>IS&C - WARD convince the world he has none"
>
Chad La Joie "Only a man who can not conquer
IT Specialist his deficiencies feels the need to
IS&C - WARD convince the world he has none"
