Hi, I have to count the number of active users. The main problem is how to trace the users who just close the browser window. The session will still alive. In my application the session time out is 4 hours. We cannot reduce that. The main requirement is to show the message "SYSTEM IS BUSY" when the number of users exceed a particular limit.
To take a possibly wild left turn ... is the real measure of a busy system the number of users? Maybe you can think of another measure - hits or throughput over last n minutes or users who did something in the last n minutes. Any other ideas?
A good question is never answered. It is not a bolt to be tightened into place but a seed to be planted and to bear more seed toward the hope of greening the landscape of the idea. John Ciardi
I have used this approach with a self-refreshing page, first in a normal frame 1 pixel wide so it wont show, and then in an inline frame. I didnt like the idea too much, but it was a must-have requirement, because the application license a placed a max-users limit. One issue with this was that if the user opens up more than one windows, there are that many more 'heartbeats' going, leading to more network traffic that originally planned for.
Will using an applet instead of the periodically refreshing page in the frame provide any benefits?