Streaming with Java: Expected ReduceByWindow to Return JavaDStream

[Jeff Nadler]

Can anyone tell me if my expectations are sane?

I'm trying to do a reduceByWindow using the 3-arg signature (not providing
an inverse reduce function):

JavaDStream<whatevs> reducedStream = messages.reduceByWindow((x, y) ->
reduce(x, y), Durations.seconds(5), Durations.seconds(5));

This isn't building; looks like it's returning DStream not JavaDStream.

>From JavaDStreamLike.scala, looks like this sig returns DStream, the
4-arg sig with the inverse reduce returns JavaDStream.

def reduceByWindow(
    reduceFunc: (T, T) => T,
    windowDuration: Duration,
    slideDuration: Duration
  ): DStream[T] = {
  dstream.reduceByWindow(reduceFunc, windowDuration, slideDuration)
}

So I'm just a noob.  Is this a bug or am I missing something?

Thanks!

Jeff Nadler