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Re: Accessibility of suBclass-fields from suPERclass (reflection)

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On 16.08.2014 10:46, Andreas Leitgeb wrote:

> Consistent maybe, but why cannot Base access these fields by default?
>
> I'm not complaining about that extra setAccessibility(true), I just
> would like to see an example of where a Base-class accessing its children
> could be a security issue.  I'm not talking of some arbitrary class
> attempting access, but about the target class's parent (or grandparent)
> class.
>
> I'm probably unaware of some risk, and learning about it was my reason
> for the posting.

If I understand your issue correctly: this is not about security but 
about design principles.  Dependency always goes up the inheritance 
chain - not downwards.  Meaning, all subclasses have knowledge about 
their superclasses but not vice versa.

If you want a superclass to access subclass state you need to provide 
means for it, e.g. defining abstract accessor or other methods in the 
base class which then must be implemented in subclasses.

There are languages out there that handle this differently.  For 
example, in Ruby instance variables are immediately accessible for all 
instance methods - regardless of their defining class.  But then again, 
Ruby has a quite different approach to visibility and accessibility.

Kind regards

	robert

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Accessibility of suBclass-fields from suPERclass (reflection) Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2014-08-15 00:58 +0000
  Re: Accessibility of suBclass-fields from suPERclass (reflection) Lew <lewbloch@gmail.com> - 2014-08-15 15:20 -0700
    Re: Accessibility of suBclass-fields from suPERclass (reflection) Steven Simpson <ss@domain.invalid> - 2014-08-16 00:11 +0100
      Re: Accessibility of suBclass-fields from suPERclass (reflection) Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2014-08-16 00:10 +0000
  Re: Accessibility of suBclass-fields from suPERclass (reflection) Arne Vajhøj <arne@vajhoej.dk> - 2014-08-15 23:26 -0400
    Re: Accessibility of suBclass-fields from suPERclass (reflection) Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2014-08-16 08:46 +0000
      Re: Accessibility of suBclass-fields from suPERclass (reflection) Robert Klemme <shortcutter@googlemail.com> - 2014-08-16 12:27 +0200
        Re: Accessibility of suBclass-fields from suPERclass (reflection) "Chris Uppal" <chris.uppal@metagnostic.REMOVE-THIS.org> - 2014-08-16 13:37 +0100
          Re: Accessibility of suBclass-fields from suPERclass (reflection) Eric Sosman <esosman@comcast-dot-net.invalid> - 2014-08-16 09:47 -0400
          Re: Accessibility of suBclass-fields from suPERclass (reflection) Robert Klemme <shortcutter@googlemail.com> - 2014-08-17 13:19 +0200
        Re: Accessibility of suBclass-fields from suPERclass (reflection) Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2014-08-16 22:37 +0000
          Re: Accessibility of suBclass-fields from suPERclass (reflection) Eric Sosman <esosman@comcast-dot-net.invalid> - 2014-08-16 20:22 -0400
            Re: Accessibility of suBclass-fields from suPERclass (reflection) Josip Almasi <joe@vrspace.org> - 2014-08-17 12:51 +0200
              Re: Accessibility of suBclass-fields from suPERclass (reflection) Eric Sosman <esosman@comcast-dot-net.invalid> - 2014-08-17 07:54 -0400
                Re: Accessibility of suBclass-fields from suPERclass (reflection) "Chris Uppal" <chris.uppal@metagnostic.REMOVE-THIS.org> - 2014-08-17 13:44 +0100
                Re: Accessibility of suBclass-fields from suPERclass (reflection) Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2014-08-17 17:42 +0000
                Re: Accessibility of suBclass-fields from suPERclass (reflection) Arne Vajhøj <arne@vajhoej.dk> - 2014-08-18 20:45 -0400
                Re: Accessibility of suBclass-fields from suPERclass (reflection) Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2014-08-20 18:47 +0000
                Re: Accessibility of suBclass-fields from suPERclass (reflection) Josip Almasi <joe@vrspace.org> - 2014-08-18 17:19 +0200
            Re: Accessibility of suBclass-fields from suPERclass (reflection) Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2014-08-17 18:04 +0000
              Re: Accessibility of suBclass-fields from suPERclass (reflection) Eric Sosman <esosman@comcast-dot-net.invalid> - 2014-08-17 15:24 -0400
                Re: Accessibility of suBclass-fields from suPERclass (reflection) Andreas Leitgeb <avl@auth.logic.tuwien.ac.at> - 2014-08-17 21:35 +0000
      Re: Accessibility of suBclass-fields from suPERclass (reflection) Josip Almasi <joe@vrspace.org> - 2014-08-16 12:31 +0200
      Re: Accessibility of suBclass-fields from suPERclass (reflection) Eric Sosman <esosman@comcast-dot-net.invalid> - 2014-08-16 10:51 -0400
      Re: Accessibility of suBclass-fields from suPERclass (reflection) Arne Vajhøj <arne@vajhoej.dk> - 2014-08-16 11:00 -0400

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