You mean Stream, right? I couldn't find any Streamable in my JDK 8: http://stackoverflow.com/questions/21985854/what-happened-to-java-util-stream-streamable

Seeing the Stream interface, though, makes me think that we shouldn't really have this interface. The "natural" thing to do with an `Iterator` is to use it into a for/foreach loop, but you can't do that with a `CloseableIterator`. How about a CloseableIterable interface instead? You could even throw an exception if the user calls the `iterator()` method more than once, but it would enable a usage like this in Java 7:

    try (entries = advancedCache.filter(filter, converter)) {
      for (Entry<K, C> e : entries) {
        ...
      }
    }

Actually, if you wanted to be fancy, you could even support stuff like `advancedCache.filter(filter).convert(converter)`, because you'd only set up the iteration when the user calls `iterator()` ;)