JDK 8 code review request for 8005298 Add FunctionalInterface type to the core libraries

[Florian Weimer]

On 01/16/2013 07:54 AM, Joe Darcy wrote:
> Hi Florian,
>
> On 1/10/2013 1:23 AM, Florian Weimer wrote:
>> On 01/08/2013 10:24 PM, Joe Darcy wrote:
>>> As discussed over on one of the Project Lambda lists [1], we're adding
>>> an interface type to the platform to explicitly mark interface types as
>>> being functional interfaces suitable for use in lambda expressions.
>>> Please review the addition of this new type:
>>>
>>>      http://cr.openjdk.java.net/~darcy/8005298.0/
>>
>> Shouldn't this annotation have @Retention(RetentionPolicy.SOURCE),
>> similar to the @Override annotation?
>
> No; we intentionally made this annotation have runtime retention to
> allow it to also be queried to various tools at runtime, etc.

This is really a bit odd.  Doesn't this risk that code will rely on the 
annotation, instead of inferring the functional interface status based 
on the interface contents?

I could not find this part in the lambda-libs-spec-experts discussion. 
Have you got a more specific pointer?

-- 
Florian Weimer / Red Hat Product Security Team