You could track the ValueBound event, and at binding time, make local
references to the session objects you are interested in. Then when you are
unbound, you do not need to worry about the order, since you have a local
reference and can still get/change information on it.
-----Original Message-----
From: Chad LaJoie [mailto:[EMAIL PROTECTED]]
Sent: Tuesday, April 10, 2001 11:54 AM
To: [EMAIL PROTECTED]
Subject: RE: Session timeouts
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"
