Sized

[Kevin Bourrillion]

On Fri, Nov 2, 2012 at 3:05 PM, Brian Goetz <brian.goetz at oracle.com> wrote:

 - It is useful to indicate that an aggregate knows its size (Collections
> do, but not all Iterables do, and we've taken advantage of this in the
> Streams library)
>

Of course, some collections, like the key set of a ConcurrentHashMap, don't
know their size any more than a garden-variety Iterable does.

So to me, this seems useful only if it is *not* a supertype of Collection.

-- 
Kevin Bourrillion | Java Librarian | Google, Inc. | kevinb at google.com