Ben's examples are a great resource. I'm glad that you are availing yourself of them.
With regards to storing the DB data to minimize future DB access, that's a classic caching
pattern. You may want to research that concept (been discussed a few times here as well).
If the data is user-specific, you probably want to cache it in the session. If the data is common to all users, application scope is a better place for it.
And the JSP is not the place to manage this cache. That's part of the servlet's job -- the JSP should be concerned only with arranging the data for viewing; keep any data processing in the servlet.