[Isolate-interest] Isolate: Generics and autoboxing considered harmful

[Miles Sabin]

Bill Foote wrote,
> However, this last rev added generics and autoboxing to the API.

Only generics ... no autoboxing.

>      2)  Every place where generics and autoboxing occur in the API,
>          include normative text saying what they map to in
>          compilation environments that don't support these new
>          features.  It must be sufficient to unambiguously specify the
>          signatures that would be present in a pre-autoboxing/generics
>          environment, and readable by someone "skilled in the art" who
>          isn't up on generics and autoboxing. 
>
> I'm of course open to other solutions.
>
> I know, it's tempting to say "well, people should know about the
> mapping," but that's not good enough for standards organizations.

I'm afraid I can't resist the temptation ;-)

The only place we use generics is on the open method on LinkMessage. The 
generic signature is,

  <T> T open(Class<T> type)

and a generic use looks like,

  String s = m.open(String.class);

On platforms which don't support generics the signature would be,

  Object open(Class type)

and a non-generic use would look like,

  String s = (String)m.open(String.class)

ie. the mapping is: erase the type parameters to the bound (Object in 
this case) and insert the necessary casts by hand.

I don't think there'd be any particular problem adding a note to the 
documentation mentioning this, but it'd just be duplicating text from 
the JLS, so is it really necessary?

Cheers,


Miles