Early jdk8-ea javadocs like this indicate there was a java.util.stream.Streamable interface, which would appear to have the same relationship to a Stream as Iterable has to an Iterator.
Now it seems like we're stuck with Supplier<Stream>, which is certainly not the same.
What happened to Streamable ?
It's been removed some time ago. The rationale for the removal was given by Brian Goetz:
Currently the only implementor is Collection, and all of the other stream-bearing methods are serving up specialized streams (chars(), codePoints(), lines(), etc) with a method name that is more suitable than "stream". So I think we should drop Streamable and leave the stream() / parallel() methods on Collection (or possibly move them up Iterable).
I'm starting to think that Streamable is not carrying its weight. I'd like to consider dropping Streamable, at which point the base-most implementation of parallel() is in Collection, and I'd also suggest we consider renaming that to parallelStream().
In this other post he adds:
if everything that is Iterable is effectively Streamable (because Iterable has a stream()) method, and everything Streamable is effectively Iterable (because you can turn a Spliterator into an Iterator), aren't they then the same abstraction?
