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: fdb77,953e1a6689d791f6 X-Google-Attributes: gidfdb77,public X-Google-Thread: fac41,953e1a6689d791f6 X-Google-Attributes: gidfac41,public X-Google-Thread: f79bb,953e1a6689d791f6 X-Google-Attributes: gidf79bb,public X-Google-Thread: 103376,953e1a6689d791f6 X-Google-Attributes: gid103376,public From: paul.johnson@gecm.com (Paul Johnson) Subject: Re: Eiffel and Java Date: 1996/11/15 Message-ID: <56hame$45@miranda.gmrc.gecm.com>#1/1 X-Deja-AN: 196616877 references: <328592FC.64F26D66@sede.unijui.tche.br> <1996Nov11.142547.4810@schbbs.mot.com> organization: GEC-Marconi Research Centre newsgroups: comp.lang.eiffel,comp.lang.ada,comp.lang.sather,comp.lang.java.advocacy Date: 1996-11-15T00:00:00+00:00 List-Id: In article <1996Nov11.142547.4810@schbbs.mot.com>, shang@corp.mot.com says... > >In article <328592FC.64F26D66@sede.unijui.tche.br> "Marcos F. F. de Macedo" > writes: >> Interfaces in Java have nothing to do with this concepts. Interface in >> Java is an implementation restriction (not a conceptual one) [...] >Separation of the interface from implementation is a good thing. >It is required by the practical software engineering needs to reduce >the dependency among software components. Maybe, but along the way from interface to implementation there is space for partial implementations containing code that is reused between the final implementations. A good example is the Eiffel "COMPARABLE" class, which defines all the comparison operators in terms of the "<" operator. So for instance the implementation of ">=" is Result := not Current < other; You can't do this in Java: every class that wants comparison operators (assuming such a thing can be defined in the language) needs to implement all of them every time. Paul. -- Paul Johnson | GEC-Marconi Ltd is not responsible for my opinions. | +44 1245 242244 +-----------+-----------------------------------------+ Work: | You are lost in a twisty maze of little Home: | standards, all different.