General talk about software patterns

[Thierry_Cattel AT eu.logitech.com]

Hello All,

I have a Domain Model for accessing some persisted information (XML) that
represent some document embedding digital writing infos.
I want to publish part of the API to third-parties (basically R/O access to
the document).

How can I organize my objects and interfaces so that they accomodate :
- Ease of use on the third-party side
- Ease of internal use (us developpers)
- As far as possible, having the same code for accessing the API in
third-party and internal mode
- Some kind of optimization : when accessing objects from the limited API,
  only part of the object should be in memory
- In case of Aggregates, when accessing the parts from the whole, the
access type (R/O or full)
  must be unchanged
- some backward compatibility
- ...
What other forces could come into consideration ?

I feel that extended object / decorator could help, but are there more
simple solutions ?

Thank you very much in adv,
even if you only provide links it would be highly helpful

Best regards
Thierry Cattel
Senior Software Engineer

Logitech Europe S.A.
Z.I Moulin du Choc D
1122 Romanel / Morges - Switzerland
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