Motivation for type-level exports

[Neil Bartlett]

Thank you Jesse. All reasonable responses are welcome, not just "official" ones.

Restricting visibility of a type that is currently public does not seem like a requirement that could be motivated by JDK modularisation, since it would break compatibility for any existing consumers of that type. It's possible that there is a need to introduce *new* types in the JDK modules that will be public but non-exported, though that seems unlikely.

In application code, why not just have package-level exports, i.e. entire packages are either exported or private?

Regards
Neil



On Thursday, 3 November 2011 at 23:35, Jesse Glick wrote:

> Not an official response but my guess:
> 
> On 11/03/2011 06:20 PM, Neil Bartlett wrote:
> > It seems that the only possible need for type-level exports could be
> > one or both of the following:
> > 
> 
> 
> 3. To permit the type to be visible to other packages in the same module, but not to other modules. In my experience this is a rather common need. If only 
> package-granularity exports are available, you can still get around this, but it is tricky, requiring a special trampoline [1]. A new access modifier intermediate between 
> public and default would be more intuitive, I think.
> 
> [1] http://wiki.apidesign.org/wiki/FriendPackages