Thank you for the reply. I implemented my InputDStream to return None when
there's no data. After changing it to return empty RDD, the exception is
gone.
I am curious as to why all other processings worked correctly with my old
incorrect implementation, with or without data? My actual codes, witho
--Original Message-
From: anoldbrain [mailto:anoldbr...@gmail.com]
Sent: Wednesday, August 20, 2014 4:13 PM
To: u...@spark.incubator.apache.org
Subject: Re: NullPointerException from '.count.foreachRDD'
Looking at the source codes of DStream.scala
> /**
>* Return a new DStre
Looking at the source codes of DStream.scala
> /**
>* Return a new DStream in which each RDD has a single element generated
> by counting each RDD
>* of this DStream.
>*/
> def count(): DStream[Long] = {
> this.map(_ => (null, 1L))
> .transform(_.union(context.sparkCon
