> Is it possible to have attributes without on an EO without a
corresponding column in the database?
I guess ~derived attributes, or some other fancy custom stuff is your best
bet.
> I ask because it is sometimes necessary to have completely transient
state associated with an EO that should never be persisted.
Unfortunately, while it is quite easy to use ObjC categories to tack on
method implementations to an EO (I can't *believe* that Java doesn't
have Categories or some equivalent functionality. What a horribly
STUPID omission! I don't *want* to use file merge every time I dump
source. DUH!).... one cannot add ivars to a class from a category.
Yes.
Yes.
Yes.
and,
Yes.
> Some perverse set of subclassing????
Without categories, you're looking at subclassing (I think).
If you step back far enough, you'll loose that feeling of nausea.
In this case, consider the the EO-generated portion of your work as an ADT.
Your custom stuff is the concrete subclass.
This is pretty flexible, just not maybe your first choice.
It is a better way of handling additional ivars, since categories don't.
