Question

For a Java JSP web application I’m making, I keep an object in a session.
If there are multiple users signed onto the site, each in their own session, I would like for all the session (regardless of when they started) to expire at midnight the same day.

For instance:

session object 1: creation date (2012-12-11 8:45), expiration date (2012-12-12 0:00)

session object 2: creation date (2012-12-11 12:00), expiration date (2012-12-12 0:00)

And so on, every day the day’s sessions getting invalidated.

Some ideas I had was

• to set the session’s time until expiration to (the next midnight – the current date), though I’m not entirely confident in my ability to progrematically do this
• schedule some kind of server task to clear all the sessions at midnight every day

What is the best way to go about this?

Answer 1

The best way I see is Option 2

1. Implement a HttpSessionListener – http://docs.oracle.com/javaee/5/api/javax/servlet/http/HttpSessionListener.html – this will help you collect the active sessions in a Collection using call back methods sessionCreated() and sessionDestroyed().
2. Use a TimerTask – http://docs.oracle.com/javase/6/docs/api/java/util/TimerTask.html that runs every midnight and closes all the active sessions you have collected.

Option 1 is also possible but might be little unpredictable as you have to set a precise timeout every time you create a new session.

Have fun !