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

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Arne Vajhøj <arne@vajhoej.dk> wrote:
> On 8/17/2014 1:42 PM, Andreas Leitgeb wrote:
>> Eric Sosman <esosman@comcast-dot-net.invalid> wrote:
>>> On 8/17/2014 6:51 AM, Josip Almasi wrote:
>>>> On 08/17/2014 02:22 AM, Eric Sosman wrote:
>>>>> On 8/16/2014 6:37 PM, Andreas Leitgeb wrote:
>>>>>> Overall-operations, (e.g. resetting all values of a given subclass
>>>>>> instance) are done from Base-class by use of reflection.
>>>>> Why by reflection?  Why not by a reset() method, abstract in
>>>>> the superclass?
>>>> Because it means coding in each subclass?
>> That really is the reason. And it's not just the reset(), but also
>> another bunch of methods.
>
> I think there are two ideas you need to consider.
> 1) Make the fields in the sub classes protected instead of private.
> This will allow you to avoid the setAccessible call.

Actually, the fields themselves are already public.  Problem was,
that the subclasses appeared in contexts that weren't "accessible",
such as within a statement block (as an inner class).

The fields are really public final references to mutable objects,
so the usual caveats about exposing public fields do not apply.

> Saving a line of code is not important, but you will also get
> rid of the restriction that your code will not run with a
> security manager in place.

That's a non-issue in my case.  (But is of course good advice
in the general case)

> 2) Replace the reflection code in the base class with a
>     cast to an interface and call of method - and use AspectJ
>     to add interface and method implementation to all sub classes
>     of the base class.

That's something I'll have get into, some day...
Until I really understand that aspect-stuff, I'm kind of
suspicious of it ;)

The separation between business and framework already exists:
the base class is framework, whereas the subclasses with their
fields are business :)

I've got a plan B, too, that would avoid reflection, but that involves
overriding a method to return an array of all the referenced objects
in each subclass.  I happily avoid that as long as reflection and
setAccessibility work well enough for me.

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Thread

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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