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Re: One sided comparison

Posted by Mike Mannion on 09 Nov 1998, 1:38 AM

For me this inheritance vs composition issue all comes down to designing solutions which

(a) most effectively model the problem at hand
(b) which permit evolution
(c) which are practical

...in roughly that order of importance.

I therefore find it quite irritating that a language mechanism - an implementation detail if you will - should oblige me to bias my design towards composition, no matter what the situation.
From the point of view of keeping both compilation and runtime semantics as simple as possible, the single class/multiple interface inheritance solution is undoubtadly a clever trick. But it has nothing to do with OO and developers would be wise to recognise this fact when crafting designs - to avoid inadvertently emphasising (c) as opposed (a).
May I suggest, therefore, that emphasis/bias which Bill has given to composition in this article is at least in part a consequence of the restrictions imposed by the Java language itself.
What do you think Bill? Has your mind been corrupted ;-) ???

• Java As It Is Bill Venners 10 Nov 1998, 10:36 AM (3)
  • Copout... Mike Mannion 11 Nov 1998, 5:41 AM (1)
    • The copout and the java API Chris Morris December 01, 2000 at 7:50 AM (0)
  • Er, that would be Bertrand Meyer Bill Venners 10 Nov 1998, 10:42 AM (0)