I guess it depends on how you structure your code. If you validate at constructor level, then you have this problem. However if you actually parse it, then thi

I guess it depends on how you structure your code. If you validate at constructor level, then you have this problem. However if you actually parse it, then this will have to be external to the actual class and you are left with a simple Value Object. This means that you can apply constraints only when it makes sense. Most of the time, there is little reason to validate something coming from the DB, so I would rather skip it. About unboxing, that depends. I would expect for the overall business logic to always use the more structured types, probably this will only be needed once you need to serialize them :) That's said, if you are happy with your current way, please keep doing it! I would still suggest to give this style a try though :)