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 autolearn=no autolearn_force=no version=3.4.4 X-Google-Language: ENGLISH,ASCII-7-bit X-Google-Thread: 103376,6fc39bb88f30631d X-Google-Attributes: gid103376,public From: Jean-Marie Wallut Subject: Re: HOOD? Date: 1996/07/04 Message-ID: <199607041313.PAA22700@imhotep.cst.cnes.fr>#1/1 X-Deja-AN: 163667377 sender: Ada programming language x-sender: wallut@imhotep.cst.cnes.fr comments: Gated by NETNEWS@AUVM.AMERICAN.EDU content-type: text/plain; charset="us-ascii" mime-version: 1.0 newsgroups: comp.lang.ada x-mailer: Windows Eudora Pro Version 2.1.2 Date: 1996-07-04T00:00:00+00:00 List-Id: Franz.Kruse@erno.de (Franz Kruse) wrote: >What is the general opinion of the Ada community about HOOD as a design method? >Franz Kruse We would like to explain why we think HOOD is an excellent design method particularly for Ada developments : - first of all we think that the concepts of the methods are very good : encapsulation (as in every object oriented method) but also hierarchy that promotes the strict definition of interfaces between separate domains at each level of the design. This last feature is very important for prototyping and/or for shared development. - complete corerage of the development process from the first brain storming to the final coding with the same technology. This changes from previous methods that used different technologies for each phase that implies translation between several formalisms (with risks of non respect of what was approved at the previous phase) - One can make a strict correspondance between the explanations he gives in the textual part of an object in his design and the code resulting from these design decisions. The layered approche makes this strict correspondance easy. Specially for Ada development each feature of the method is directely implemented by an Ada feature (a parent object is a package specification, a terminal object as a body for implementing his "duty", an internal data is a variable in the body etc....). Some rules have been added thant enhance the quality of the generated Ada (for example it is forbidden to offer a data in the provided interface of an object that is to say in an Ada specification : this avoid data to be modified by any client of the object responsible of the data. - More and more the design can be independant from the design tools. The concept of SIF (Standard Interchange Format) allows to bring a design from a tool to another one (even if the SIF does not take into account some aspects as the graphical aspect of the solution and also if the tools do not all implement perfectly the SIF import/export). Our opinion is based on our personnal feeling from personnal developments but also on the fact that at the moment each project developped in Ada in our company is designed in HOOD and the results are good in most of the cases. Last point to focus on is that the method is evolving to take into account the new concepts of Ada 95 that is to say inheritance an polymorphism. These new possiblities combined with hierarchy (as soon as one knows how to use properly both features together) can make of HOOD an even more powerful method. ====================================================================== __ __ ___ ___ | Denis Minguillon & Jean-Marie Wallut / / \ /___\ /___ | CT/TI/PS/MP Bpi 1501 \____| | \____ ____/ | CNES - 18, av. Edouard Belin | 31055 Toulouse Cedex (FRANCE) Centre National | | Tel : (33) 61 27 34 49 d'Etudes Spatiales | Fax : (33) 61 27 30 84 | E-Mail : wallut@cst.cnes.fr =====================================================================