What would be the advantage of logging the sessionDestroyed event just to be safe. I'm currently solving problems with counting the number of active sessions and would like to know about the strategy of doing so.
Thanks in advance, Kevin -----Original Message----- From: Shapira, Yoav [mailto:[EMAIL PROTECTED] Sent: Tuesday, August 12, 2003 9:15 AM To: Tomcat Users List Subject: RE: HttpSessionListener: Negative session count Howdy, The simple check you had before (if session count < 1 don't decrement) is not a bad idea. You might want to log the sessionDestroyed event just to be safe. In the 2.4 servlet spec, you will have other options (notifications) that apply to this scenario I think. Yoav Shapira Millennium ChemInformatics >-----Original Message----- >From: Christian Hauser [mailto:[EMAIL PROTECTED] >Sent: Tuesday, August 12, 2003 10:14 AM >To: Tomcat Users List >Subject: Re: HttpSessionListener: Negative session count > >Hi Yoav > >That could be the problem as well. So if the server is restarted my >session counter variable is set to 0, but there might still be 30 active >sessions. > >I didn't think of that problem, because I thought that the sessions >would be invalidated when the server is restarted. > >Has anyone a good solution to this problem? Or should I just prevent the >session counter variable from becoming negative and after a while >(session timeout for all remaining sessions) the counter will be working >correctly again? > >Cheers, > Christian > > >Shapira, Yoav wrote: > >> Howdy, >> I would mention one other possibility, unrelated to synchronization, >> which may cause this behavior. >> >> If your session listener simply increments a counter on every >> sessionCreated() and decrements the counter on every sessionDestroyed(), >> it is vulnerable to this behavior. >> >> When the server is restarted, if there are active sessions they are >> persisted by default. Then the server comes back up, and all these >> sessions are active, without a session created event, so your listener >> has a counter value of 0, but there are actually >0 active sessions. >> When these are destroyed as usual, sessionDestroyed() will be called for >> them, decrementing your counter and resulting in a negative value. >> >> Yoav Shapira >> Millennium ChemInformatics > > > >--------------------------------------------------------------------- >To unsubscribe, e-mail: [EMAIL PROTECTED] >For additional commands, e-mail: [EMAIL PROTECTED] This e-mail, including any attachments, is a confidential business communication, and may contain information that is confidential, proprietary and/or privileged. This e-mail is intended only for the individual(s) to whom it is addressed, and may not be saved, copied, printed, disclosed or used by anyone else. If you are not the(an) intended recipient, please immediately delete this e-mail from your computer system and notify the sender. Thank you. --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED] --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
