Problem of defender methods with generic methods

[Alex Buckley]

On 11/15/2010 4:52 PM, Steven Simpson wrote:
> Could it be done like this?:
> 
> interface List<T> {
>   ...
>   <new T extends Comparable<? super T>> extension T max() default Collections.max;
> }
> 
> The generic method signature as it appears in the bytecode would be
> almost the same, but with some extra flag on T, e.g. '!':
> 
> <!T::Ljava/lang/Comparable<-TT;>;>()TT

It could, but don't forget to document the impact of additional bounds 
on subtyping (notably, containment of type arguments) and inference. The 
real question is whether library evolution commonly needs to so restrict 
type variables in the first place.

Alex

P.S. A better use of the "new" token in the context of a bound is to 
mandate that witnesses of a type variable have a no-args constructor, so 
you can say "new T()" in the body. But that's another story.