PROPOSAL: Return 'this'

[Gabriel Belingueres]

Wouldn't it be simpler to add a Pascal-like "with" statement? This
would solve at least the method chaining issue:

with(object) {
  method1();
  metohd2();
   ...
  methodN();
}


2009/3/26, Marek Kozieł <develop4lasu at gmail.com>:
> 2009/3/26 Tom Hawtin <Thomas.Hawtin at sun.com>:
> > Marek Kozieł wrote:
> >
> >> MAJOR ADVANTAGE:
> >> Simplification of "return this" statement.
> >> 'void' can be easy replaced with 'this'.
> >>
> >> MAJOR BENEFIT(s): It would prevent NullPointerException, and make some
> >> 'builder' like interfaces look really clear and simple.
> >
> > My problem with this is that it is an attempt to fix a hack due to a
> > language problem with a language hack.
> >
> > The underlying problem is that Java does not have a concise syntax for
> > builders. The usual hack is for builders to return this and clients to use
> > method chaining. This solution makes the hack easier. A better solution
> > would be direct, explicit support for builders in some form.
> >
> > Also the variant of this proposal that client-side reinterprets returning
> > void to return this, would interfere to some extent with covariantly
> > returning void when overriding a return of Void.
> >
> > Tom Hawtin
> >
>
> This is some point.
> I do not like it just because in need to be served outside, which
> increase interactions.
> Notice that this will work totally in unexpected way when:
>
> we have a.jar & b.jar
> while both are compiled and b.jar use a.jar, than some one change (in a.jar )
>    interface A{ this some(); }
> to:
>    interface A{ A some(); }
> because he want to return other object...
>
> this would work in pretty unexpected way.
>
> BTW.
> Did you wander if Interfaces / abstract classes should be final  (with
> explicit declared classes/interfaces available for inheritance), like:
> final interface A allow Ab, Ac{...}
> this was my idea connected to inheritance security.
>
> --
> Pozdrowionka. / Regards.
> Lasu aka Marek Kozieł
>
> http://lasu2string.blogspot.com/
>
>