The implementation of default methods

[Doug Lea]

On 12/16/12 21:39, David Holmes wrote:
> On 16/12/2012 1:56 AM, Brian Goetz wrote:
>> For Iterator.remove, I think the real constraint is: the JDK must
>> provide *a* default implementation (since this is only an issue for
>> compatibility across JDKs). Since the only reasonable default would be
>> to throw something, we might as well specify what is thrown, since this
>> degree of freedom serves noone: the JDK must provide a default that
>> throws UOE.
>
> One example does not a policy make. We have to address the general issue not, I

Especially the corner case of always throwing an exception,
which generalizes only to those default implementations
in which there is only one plausible way to do something,
so the javadoc might as well say exactly what it does.

>
> On a related but separate note, the "is equivalent to" approach has caused not
> insignificant confusion over the years because no one knows exactly what it
> means

I'd put the "exactly what it means" in the supporting docs
(maybe technotes/guides/collections/index.html) that will
need an overhaul anyway. It's not hard to rigorously define.

-Doug