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From "Vamsavardhana Reddy" <c1vams...@gmail.com>
Subject Re: Anyway to get the generic type from a generic class?
Date Mon, 01 Oct 2007 06:31:36 GMT
On 10/1/07, Jason Dillon <jason@planet57.com> wrote:
>
> Alright... thanks, that is what I figured :-(  So lame... I can
> figure out that a class as T and E bound, but I can't figure out the
> type of those buggers...


The underlying object does not impose any restrictions as such (and so there
is nothing special about these objects).  It is only for the compiler that
will help you prevent using some undesired type unknowingly (for e.g, adding
String to a Integer list).  I guess it is evident from the  example in my
last post.


so stupid :-(
>
> --jason
>
>
> On Sep 30, 2007, at 11:08 PM, David Jencks wrote:
>
> >
> > On Sep 30, 2007, at 10:48 PM, Jason Dillon wrote:
> >
> >> Any of you generics experts out there know if there is any way to
> >> get the generic type from a generic class... like, say you have:
> >>
> >>     Class type = new ArrayList<String>().getClass();
> >>
> >> Is there any way to determine that this is an ArrayList containing
> >> String objects?  I can't seem to figure out how to get this
> >> information out of the Class instance.  I can figure out what the
> >> type variable name was, er like T, but that is well, completely
> >> useless IMO.
> >>
> >> Does anyone know if its possible and how to do it?
> >
> > I spent a couple days reading up on generics and trying stuff and
> > concluded it was not possible.  There are some statements in the
> > book on generics that confirm this.  Hopefully you will find a way
> > to prove I'm wrong 'cause it sure would be handy :-)
> >
> > sorry
> > david jencks
> >
> >>
> >> --jason
> >
>
>

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