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From: Eric Sosman <esosman@comcast-dot-net.invalid>
Newsgroups: comp.lang.java.programmer
Subject: Re: Accessibility of suBclass-fields from suPERclass (reflection)
Date: Sat, 16 Aug 2014 20:22:16 -0400
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On 8/16/2014 6:37 PM, Andreas Leitgeb wrote:
> Robert Klemme <shortcutter@googlemail.com> wrote:
>> On 16.08.2014 10:46, Andreas Leitgeb wrote:
>>> 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.
>
>> 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.
>
> I'll describe my situation a bit:
>
> I have a special Base class, and each of its subclasses serve exactly
> one purpose: a collection of name/value associations where the java-
> compiler knows about the valid names, so as to detect accesses to
> non-existing names already at compile-time.  (without that last premise,
> I would have used HashMaps instead of subclasses)

     Would an EnumMap serve?

> 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?

     I'm confident you have reasons, but I'm sure I haven't yet
grasped them.


-- 
esosman@comcast-dot-net.invalid