Best way to implement application level persistant objects?

I'm designing a J2EE application and want to create some objects that represent lookup tables in the database. I would like these to be static objects that get created either at application startup or the first time they are called and remain in application scope globally for all users/sessions. These are objects that contain lists used for drop-downs/listboxes. I don't necessarilly want to take up unecessary memory
and take a performance hit for each session by creating them new for each session. The question is what is the recommended design for this scenario? Should these be implemented as static Stateless Session beans with an application scope? Are there any examples on the best way to do this in J2EE?
Thanks.

You can simply (and properly) implement the Singleton pattern. Then multiple threads can all query the cached reference table values in the Singleton. Now, I know, that Singletons and J2EE are supposedly no-no's, but sometimes the easiest and simplest solution really is the best one. Perform the database query at startup in a static initializer. Then ensure that you do not have mutator methods (e.g., removeXXX(), setXXX(), addXXX(), etc.) Only provide accessor/getter methods. If you want to be able to refresh the cache without restarting the server, you will have to think about race conditions. But if you are implementing a vanilla cache, I would go with a Singleton.
- Saish
"My karma ran over your dogma." - Anon

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