From mboxrd@z Thu Jan 1 00:00:00 1970 X-Spam-Checker-Version: SpamAssassin 3.4.4 (2020-01-24) on polar.synack.me X-Spam-Level: * X-Spam-Status: No, score=1.3 required=5.0 tests=BAYES_00,INVALID_MSGID, MSGID_RANDY autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,39e272d357c68416 X-Google-Attributes: gid103376,public From: reason67@my-deja.com Subject: Re: Is Apex dead as an environment for Ada & Java? Date: 1999/11/29 Message-ID: <81u6sh$l7k$1@nnrp1.deja.com>#1/1 X-Deja-AN: 554432819 References: <11f733ec.57d88b68@usw-ex0107-042.remarq.com> <384127A5.61431A14@dowie-cs.demon.co.uk> <0a0133f8.3baf10c0@usw-ex0101-001.remarq.com> <81s370$7am$1@nnrp1.deja.com> <0a0133f8.7900d89e@usw-ex0102-015.remarq.com> X-Http-Proxy: NetCache@www-blv-proxy5.boeing.com: Version NetApp Release 3.4D6: Mon Aug 23 16:40:19 PDT 1999-Solaris, 1.0 x38.deja.com:80 (Squid/1.1.22) for client 12.13.226.15 Organization: Deja.com - Before you buy. X-Article-Creation-Date: Mon Nov 29 15:42:17 1999 GMT X-MyDeja-Info: XMYDJUIDreason67 Newsgroups: comp.lang.ada X-Http-User-Agent: Mozilla/4.05 [en]C-Boeing Kit (Win95; I) Date: 1999-11-29T00:00:00+00:00 List-Id: In article <0a0133f8.7900d89e@usw-ex0102-015.remarq.com>, jim_snead wrote: > In article <81s370$7am$1@nnrp1.deja.com>, mike_zebrowski@my-deja.com > wrote: > > This approach is simple and enforceable. I don't > like the fact that Apex has features as complicated > as subsystems to accomplish this simple effect. > The tool effectively locks you into a specific approach > and you become a captive Apex customer because > of some outrageous marketing features. 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. 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. 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. 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. --- Jeffrey S. Blatt Sent via Deja.com http://www.deja.com/ Before you buy.