RFR: 8028816: Add value-type notice to Optional* classes

[Paul Benedict]

Florian, it's an idea I also broached but did not receive any feedback:
http://mail.openjdk.java.net/pipermail/lambda-libs-spec-observers/2013-December/002585.html

The only downside to adding the annotation is that it makes it "the"
official way to denote a value type. Based on some JEPs and Lambda
mailings, I think there's some heavy discussions behind the scenes to
explore this design space. I don't know if committing to an annotation
at this point is the "right" solution.

-- 

Cheers,
Paul


>* There's been a discussion on the lambda spec experts list (http://mail.openjdk.java.net/pipermail/lambda-spec-experts/ <http://mail.openjdk.java.net/pipermail/lambda-spec-experts/>) about adding a notice to the Optional classes about implications of their likely future as values. This discussion recently completed so now there's a doc patch to review:
*>>* http://cr.openjdk.java.net/~mduigou/JDK-8028816/0/webrev/
<http://cr.openjdk.java.net/%7Emduigou/JDK-8028816/0/webrev/>
*>>* I have already reviewed this but will hold off pushing it for a
few hours in case someone notices a mistake that I did not.
*
Would it make sense to have an annotation (with class file retention) to
express this?

-- 
Florian Weimer / Red Hat Product Security Team