Re: Is Apex dead as an environment for Ada & Java?

[jim_snead <basswoodNObaSPAM@my-deja.com.invalid>]

In article <81u6sh$l7k$1@nnrp1.deja.com>, reason67@my-deja.com wrote:
> The reason for subsystems is to encapsulate components withing a
> software hierarchy. For instance, if I was working on a simple
> Fighter simulation, I might want a subsystem for universals_types,
> low_level_utilities, then build subtrees based on common radar
> functionalities, common flight functionalities, weather, etc.
> Then, for example in the flight, I could break i down further into
> flight_common, cockpit_displays, aerodynamics, etc. etc.

These are way too big of chunks for subsystems.  I would
say a hierarchy (i.e. individual subsystem) would be examples
such as the Linux operating system, the source code to GNAT,
or the Mozilla-Netscape source.  Why on earth would you want
to apportion these into smaller subsystem chunks?

> What I gain is the ability to enforce a design onto 50 - 100
> developers.
> This would prevent a flight developer from using a subprogram
> developed
> by a weather developer. This enforces loose coupling between
> unrelated
> features. If the weather developer needs to eliminate or modify his
> subprograms, he is guarenteed not to effect the other in unrelated
> areas of the simulation.

Apparently Apex does allow the mutual importation of subsystems.
I don't understand, does Apex enforce this policy or doesn't it?
I have my include paths as an example to rigidly enforce
such a policy without requiring Apex.

> Can I do this other ways in Ada95? Sure. But I can only do it in Ada95
> by enforcing a coding requirement on the developers, and not just a
> design requirement. (your package heirarchy example).
> Subsystems serve another purpose as well, as someone else pointed
> out,
> Apex code exists in views. The code is shared in a subsystem and
> implemented in views. The Subsystems enforce the CM.

Here is the way to do it in CVS

- CVSROOT
    - history1
         - subdir1
         - subdir2
    - history2
         - subdir1
         - subdir2

- Integration "view"
    - history1-subdir2
    - history2-subdir1

I doubt Apex does it any different. In which case this is
very basic functionality. In my example, the CVSROOT
enforces the CM responsibility.  I suppose
you could have different CVSROOT paths which
would be the equivalent of different subsystems.
But I would only do this if I knew I was
going to develop both Linux, GNAT, and Netscape
at the same time. Which is very doubtful.

> None of this makes Apex a requirement for Ada95 obviously and you
> may consider the overhead to be too great or the cost prohibitive, but
> it certainly does not mean that Apex subsystems serve no purpose or
> are antequated. I have always found them to be quite useful on large
> projects.

No I am only trying to figure out a path forward.  Rational
has many products that seem to cannibalize each other
such as Apex, ClearCase, and Summit.  Each one of these
is claimed to be the way to go for large software systems
development.




* Sent from RemarQ http://www.remarq.com The Internet's Discussion Network *
The fastest and easiest way to search and participate in Usenet - Free!