Re: [T] Clean Object Class Design -- What is it?

"Topmind" <topmind_at_technologist.com> wrote in message
> >
> > My primary domain is military applications. Areas I've worked in range
 from
> > command and control systems (which resemble commercial enterprise data
> > systems), intrusion detection, combat simulations, embedded controllers,
> > radar surveillance (embedded apps), to VLDB systems involving the
 retrieval
> > of intel data.
> >
>
>
> Interesting. I suppose you could not share specifics about what
> the subclasses you intend to use? I am not much of a fan of
> OO with business applications. Those that try to persuade me that OO is
> great usually fall into two camps:
>
> 1. One doesn't really need to use subclassing
> to get benefits from OO.
>
> 2. Subclassing (and polymorphing off those subclasses)
> is quite useful in biz apps, but Topmind just cannot
> recognize them.
>
> If it's #1, then how does OO improve it? If it's #2,
> then please list decent, stable biz taxonomies
> in outline form that non-me's have discovered.
>

As I've mentioned before (maybe it wasn't this thread), I'm not in favor of using OODBMSs in "biz" (by that I assume you mean enterprise data stores ... diverse apps hitting central data) applications. The command and control system I put in place used an RDBMS, and I wouldn't even consider for a moment replacing it with an OO-type system.

Now, one area I wanted to use an OODBMS and couldn't was in combat simulation. Here we have classic inheritance taking place. As an example, there are numerous kind of entities in the system interacting with each other. It's convenient to break these entities down into subclasses such as "combat" and "non-combat." Combat entities clearly have a different set of characteristics from non-combat entities, but both are capable of interacting with each other in the system. Within combat entities, you find Air, Land, and Sea (plus some mixed units I won't detail here). I'm sure you begin to get the picture. A decent theater-level simulation will have 5,000 - 10,000 of these entities running about. Additionally, each entity has missions assigned to them, which in turn have their own hierarchy (for example, air missions can be offensive counterair, defensive counterair, strike, escort, suppression of enemy air defense, etc.). Lots of opportunity to use inheritance.

>
> > Currently I've moved an abstraction level above databases,
>
> Rather than fiddle with yet another layer, I try to
> "surf" the database features and take advantage of it's
> inherit power.
>

Let me be a bit more clear about what I mean, my current work involves retrieving information from structured and un-structured sources. This means I not only have to deal with databases, but I have to deal with documents (both unstructured and structured in various forms) ... all in the same "query." That means working at a higher abstraction level. It's interesting. Received on Sun Jul 08 2001 - 18:41:42 CEST