I'm working on a simple application for a game in Java that allows a user to record whether they have collected a given item and how much experience it contains. This will work for multiple item types (weapons, armor) and each will have its own tab with a list of all items that qualify under it. Making changes as new types are added is not such a big deal (if a clothing slot is added, for instance), but new items are added to the game all the time in biweekly patches, and I'm not sure what the traditional/customary way to make sure the application is user-extensible without requiring me to would be.
Whether that would be adding a configuration menu that allows users to add news items (new rows to the local SQLite database) or a text file with something similar, but I'm certain there's a well-accepted way to do this that I'm not aware of. I'm new to databases and ignorant of the solution, so what's the professional/futureproof way to do this?