Simplifying reified generics with partial specialization

Gavin King gavin at
Mon Jan 5 19:52:34 UTC 2015

On Mon, Jan 5, 2015 at 1:10 PM, Ron Pressler <ron at> wrote:

> This would mean that ArrayList<int> will implement List<Integer> (and will
> therefore extend List and List<?>)

Ron I think this would be a bad idea. Yes, I know that Java
unfortunately doesn't provide a typesafe null value, but I still think
that it would be a bad idea to have occurrences of "int" which
actually mean int|null. I think there's a really strong precedent in
the language that ints can't be null.

OTOH, perhaps it would be viable to make ArrayList<int> a subtype of
ArrayList<? extends Integer>.

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