Thanks..
i think i figured out what i'm going to wind up doing.
We plan on funneling all similar inbound interfaces into "interface flows".
For instance, let's take AP:
We have 10 sources of Vendor invoices. They ALL do the same thing once we get them into SAP - create an invoice (FB01). However, file formats are different.. certain invoices need additional enriched data etc....
All that enrichment and validation will be handled in an AIF action.
BUT, since they all basically do the same thing, the converted data will all flow into the same Ztable.
We build a single workbench on top of this Ztable for error invoice verification and posting.
What I will do is create a superclass for the AP posting and instead of making it so generic, I'll be using the structure of the Ztable.
That way all subclasses will use the same DDIC structure because all the data is stored in the same Ztable.
This is actually how I have my existing AP interface flow setup currently.
I was just hoping I could find a way to have 1 superclass that inherits to any other AP subclass even if the DDIC structures would be different. But, as Sandra pointed out above, that is really making an API out of an API.