Path: utzoo!attcan!uunet!mailrus!cs.utexas.edu!know!samsung!xylogics!merk!alliant!linus!community-chest!mitchell
From: mitchell@community-chest.uucp (George Mitchell)
Newsgroups: comp.software-eng
Subject: Re: OOP and software reuse
Message-ID: <112789@linus.mitre.org>
Date: 9 Jul 90 15:07:02 GMT
References: <39400113@m.cs.uiuc.edu>
Sender: usenet@linus.mitre.org
Reply-To: mitchell@community-chest.mitre.org (George Mitchell)
Organization: MITRE-McLean Software Engineering Laboratory
Lines: 26

In article <39400113@m.cs.uiuc.edu> johnson@m.cs.uiuc.edu wrote:
`....
`The purpose of software reuse is not to eliminate programming but to
`eliminate *unnecessary* programming.  Although some of what we do
`when we design new systems is creative, some of it is routine, simply
`regurgitating algorithms and data structures that we have learned
`in the past.  Software reuse lets us stop regurgitating.  In other
`words, it will eliminate that part of building software that is
`predictable and so emphasize the creative part that is not predictable.
`In that sense, object-oriented programming is going to make the problem
`that Cliff mentions worse.  However, it will greatly decrease the amount
`of time that it takes to build software.  Managers still won't know how
`much time it takes to build software, but they will know that it takes
`less time than it used to.

This emphasis on programming and building reflects much of what I think is
wrong about the way we usually view reuse.  The major cost of software is in
maintenance, not development.  The major cost of development is not in coding.
To gain the greatest benefit from reuse, we need to have components that can
be incorporated without alteration, without unit test, and without subsequent
maintenance.  What needs to be available in the component market place is not
only code, but test data, warranties, and life cycle support.
--
George Mitchell, MITRE, MS Z676, 7525 Colshire Dr, McLean, VA  22102
email: gmitchel@mitre.org  [alt: mitchell@community-chest.mitre.org]
vmail: 703/883-6029         FAX: 703/883-5519