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How many Session Objects ??

Saima Khan

Joined: Jan 15, 2002
Posts: 6
Hello All,
I want to know that how many users currently communicating with my web-application .Is there
any way to find out Using Java Servlet Api may be using ServletContext .
I appreciate any help .
Mike Curwen
Ranch Hand

Joined: Feb 20, 2001
Posts: 3695

From the Tomcat-Users mailing list:
In a servlet 2.3 environment (Tomcat 4), you can accomplish your goal
without getting into the innards of the container. Simple create and
register an HttpSessionListener, which will be notified every time a
session within your app is created or destroyed -- it's easy to maintain a
local HashMap (or something) of the currently active sessions.

Does anyone know if there's a way to get some kind of a reference to all of
the active sessions in a webapp? I just want to know how many Sessions
there are.
I'd just like to be able to say something like "There are currently X Number
of users online" on some page.
-Cavan Morris
Saima Khan

Joined: Jan 15, 2002
Posts: 6
Hello Carig,
Thanks for your reply ,but actually you repeated my question .As I was also asking about the no of users currently online to communicate simultaneously with any web-aps.
This is interesting thing and there must be some solution .
Thanks anyway .

Saima Khan.
Mike Curwen
Ranch Hand

Joined: Feb 20, 2001
Posts: 3695

Umm.. I think you need to read that again.

This is Mike, posting a request/response email from two other people, one of whom is named Craig.

(At least one) solution to your problem is *in* that quote. Extrapolate beyond the information given. Think HashMap.size()
[ January 16, 2002: Message edited by: Mike Curwen ]
Saima Khan

Joined: Jan 15, 2002
Posts: 6
Hello Mike ,
Sorry for the misunderstanding .
But I am still unable to know the total no of users using HttpSessionListener.
Sandeep Jain
Ranch Hand

Joined: Oct 25, 2000
Posts: 124
Well Khan ,
What u need to do is this ..
1) u need to declare a Haspmapor a Hashtable in the class. This u must me doing(i hope) to keep track, that the user doesnt log on two from two machine simaltaneously , any how even if u havent ,no problem .
2) everytime a user logs on to the ur web
application u have to check whether his login name is already there or not . if it is not there u put his name in the map .
3) every time a person logs out, u remove his name from the hashmap
4) now to find out what exactly ur requirement is what u can do is , u can call size() of the hashmap or table .which will return u the count of number of people who are using your application

Try and Try Till u succeed<br /> <br />Sandeep Jain
Saima Khan

Joined: Jan 15, 2002
Posts: 6
Thanks a lot Sandeep.
I think now i will solve this if I need anything else further i will let you know .
Thanks again.
satyendra adhikari
Ranch Hand

Joined: Aug 17, 2001
Posts: 52
sandeep how do you remove user name from your case of session time out..
Bosun Bello
Ranch Hand

Joined: Nov 06, 2000
Posts: 1510
Satyendra, you will need to implement the HttpSessionBindingListener interface, and put the code to update the hashtable in the value unbound method.

So much trouble in the world -- Bob Marley
I agree. Here's the link:
subject: How many Session Objects ??
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