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Re: vocabulary

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On 28.04.14 00.30, Martin Gregorie wrote:
> It seems to me that the only reason Java has both Abstract Class and
> Interface definitions is to sidestep having to implement multiple
> inheritance:

Yes the implementation of interfaces is different from that of classes.
In fact this is the point where java already supports multiple 
inheritance. Accessing an interface requires another level of 
indirection because of this difference.

> if multiple inheritance was supported there would be no
> difference between them.

This is exactly the way that C++ has gone. There the people claim that 
they need to write "public virtual Name" to implement an interface. And 
from time to time the "virtual" is missing, which leads to different and 
with respect to interfaces unexpected behavior. Others (accidentally) 
add data members to the interfaces which actually should not happen to 
interfaces.

> That said, I seldom use Interface definitions
> but find the distinction can be useful.

Interfaces are used in Java quite often. Mainly to implement the PIMPL 
and/or the factory pattern.


Marcel

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vocabulary Roedy Green <see_website@mindprod.com.invalid> - 2014-04-26 21:09 -0700
  Re: vocabulary markspace <markspace@nospam.nospam> - 2014-04-26 21:25 -0700
    Re: vocabulary "Qu0ll" <Qu0llSixFour@gmail.com> - 2014-04-27 17:30 +1000
  Re: vocabulary Richard Maher <maher_rjSPAMLESS@hotmail.com> - 2014-04-27 14:42 +0800
  Re: vocabulary Marcel Müller <news.5.maazl@spamgourmet.org> - 2014-04-27 08:59 +0200
    Re: vocabulary "Qu0ll" <Qu0llSixFour@gmail.com> - 2014-04-27 17:33 +1000
      Re: vocabulary Marcel Müller <news.5.maazl@spamgourmet.org> - 2014-04-27 12:21 +0200
        Re: vocabulary "Qu0ll" <Qu0llSixFour@gmail.com> - 2014-04-27 20:23 +1000
          Re: vocabulary Roedy Green <see_website@mindprod.com.invalid> - 2014-04-27 12:52 -0700
            Re: vocabulary Martin Gregorie <martin@address-in-sig.invalid> - 2014-04-27 22:30 +0000
              Re: vocabulary Marcel Müller <news.5.maazl@spamgourmet.org> - 2014-04-28 08:23 +0200
              Re: vocabulary "Chris Uppal" <chris.uppal@metagnostic.REMOVE-THIS.org> - 2014-05-04 13:00 +0100
                Re: vocabulary Eric Sosman <esosman@comcast-dot-net.invalid> - 2014-05-04 08:44 -0400
  Re: vocabulary lipska the kat <lipskathekat@example.com> - 2014-04-27 09:01 +0100
    Re: vocabulary "Qu0ll" <Qu0llSixFour@gmail.com> - 2014-04-27 19:53 +1000
      Re: vocabulary lipska the kat <lipskathekat@example.com> - 2014-04-27 11:43 +0100
  Re: vocabulary Jeff Higgins <jeff@invalid.invalid> - 2014-04-27 07:14 -0400
  Re: vocabulary Jeff Higgins <jeff@invalid.invalid> - 2014-04-27 07:32 -0400

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