OOA/D and Corba/IDL: A Common Base

Re: The OMG's efforts on OOA/D Methods and IDL

The OMG has launched a renewed effort to work towards a common basis for OOA/D
methods and for IDL extensions. The goals of this effort, through the current
RFI and upcoming RFPs, include:

- Identify a common semantic basis for OOA/D methods and meta-models
- Identify extensions to IDL towards behavioral specification
    (i.e. beyond plain signatures)
- Work towards a common repository model and tool interchange facilities

The paper listed below outlines an approach to addressing these needs. The
paper is available for Web access, or postscript may be downloaded.

OOA/D and Corba/IDL: A Common Base 

Abstract: The OMG's principal aims of widespread re-use and interoperability
cannot be realized without precise, abstract behavioral definitions of
interfaces and architectures. Interoperability of models and specifications
across OOA/D methods and tools requires them to have a common semantic
basis. Since specification constructs will vary, any solution must be flexible
enough to permit a component to be selected based only on those parts of its
specifications that a search tool understands.

This paper shows how "traits" -- individual named properties --- form a
semantic basis for interchange of behavioral descriptions. Traits are composed
into "theories", bodies of knowledge about specifications, types, modeling
constructs, framework descriptions, and so on. Theories build upon each other
by import. Everything from OOA modeling constructs, down to the nature of
objects and basic ideas of logic is expressed in the theory heirarchy, rather
than built into the notation itself. Every trait is asserted within the context
of a theory containing everything that must be understood to make complete
sense of it.

The paper shows how specifications written in different OOA/D notations can be
given a solid semantics by translation to theories. Different notations have
different underlying object models --- themselves expressed as theories.  To
switch from one notation to another, substitute a different theory of
objects. Systematic translations from one theory to another can be defined.  We
illustrate with an extension to IDL for behavioral specification, and with
OOA/D constructs as defined in the "Catalysis" method.


The paper is available on-line from:
<A HREF="http://www.iconcomp.com/papers"> OMG, OOA/D, and IDL </A>
(Web-browsable or postscript)
The same location also has a detailed description of the Catalysis method.

* ICON Computing, 12343 Hymeadow Dr., Suite 3C, Austin, TX 78750            *
* Phone: 512.258.8437      Fax: 512.258.0086      email: info@iconcomp.com  *
*       For a growing OO repository visit: http://www.iconcomp.com          *