JDO Appengine Paradigmns
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I've just started dabbling in google ape engine.  Right now I'm using JDO with the datastore to persistent my data. Pretty cool so far and I have most everything working the way I want.  However, I have a few standard practice questions.  My instinct tells me there are several design choices i made that aren't the best if not outright bad.

   Do you generally have a "wrapper" type class to handle gets, updates, inserts and deletes for each persistent object?(this feels like overkill)

   I don't do any type checking on Query.execute?(this really seems wrong)

   All my classes use IDGeneratoryStrategy.IDENTITY in each object which could be in a base class I guess?

As i said I just started dabbling in this as the questions above demonstrate but any input or links would be greatly appreciated.  FYI my end result is to use the app engine as the datastore for android apps.  However, the more I've see of appengine I think I can use it for more things than just storing data for my android apps.