Interfaces were added to Java because they didn't want to (for reasons
I fully appreciate) do multiple inheritance, which would have provided
equivalent functionality (and then some). Interfaces are, IMO, very
much worthwhile, but they do come at a significant performance cost vs
pure virtual calls. They also provide nothing in the way of access
control.
On Oct 27, 7:26 pm, William Ferguson <william.ferguson...@gmail.com>
wrote:
> > ("Interfaces", by the way, are just a "poor man's" subclass -- very
> > little conceptual difference.)
>
> *choke*
>
> Uh OK. I'll leave it there.
> I hope that one day you will see the difference.
>
> On Oct 28, 8:32 am, DanH <danhi...@ieee.org> wrote:
>
> > Android (and Java) would never have been built without subclasses.
> > True, with a good suite of APIs you may never need to subclass
> > anything, but that's simply because the people who designed the APIs
> > were skillful in using the full power of the OO model.
>
> > ("Interfaces", by the way, are just a "poor man's" subclass -- very
> > little conceptual difference.)
>
> > On Oct 27, 5:20 pm, William Ferguson <william.ferguson...@gmail.com>
> > wrote:
>
> > > Sorry Dan, I have to strongly disagree with '"Subclasses", on the
> > > other hand, are the "meat
> > > and potatoes" of OO programming".
>
> > > IMHO subclasses are typically the most abused part of OO programming
> > > and are often a cause of obscure programming bugs. The Android API is
> > > a good case in point, many of the widget classes require you to
> > > subclass them in order to provide additional functionality but don't
> > > give you access to the attributes you need. IMO one of the main
> > > failures of the Android API is that it makes too heavy use of
> > > implementation inheritance (subclassing) rather than interfaces.
>
> > > I rarely subclass. I find I can get a much cleaner abstraction using
> > > interfaces and composition.
> > > And when I do subclass I keep the responsibilities and methods locked
> > > down tight.
>
> > > Subclassing is a slippery slope that gets steep really fast.
>
> > > On Oct 28, 3:50 am, DanH <danhi...@ieee.org> wrote:
>
> > > > First you need to understand that "inner classes" and "subclasses" are
> > > > two distinctly different things. "Inner classes" are mostly just a
> > > > convenience, simplifying coding without actually providing significant
> > > > additional function. "Subclasses", on the other hand, are the "meat
> > > > and potatoes" of OO programming and provide power, function, and
> > > > security advantages that are so substantial that few programmers ever
> > > > grasp their full potential.
>
> > > > On Oct 26, 9:27 pm, zeeshan mirza <zeeshan.nabeel.mi...@gmail.com>
> > > > wrote:
>
> > > > > Frank thank you for your answer. I know some points when do we need to
> > > > > create inner classes like we cant extend more than one class so if we
> > > > > create inner classes we can extend more classes. Am i right? is there
> > > > > any other advantage of inner classes ?
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