The error message indeed is not very clear.

What you did wrong is that the repartitionAndSortWithinPartitions not only 
requires PairRDD, but also OrderedRDD. Your case class as key is NOT Ordered.


Either you extends it from Ordered, or provide a companion object to do the 
implicit Ordering.


scala> spark.version
res1: String = 2.1.0

scala> case class DeviceKey(serialNum: String, eventDate: String, EventTs: Long)
extends Ordered[DeviceKey] {
     |   import scala.math.Ordered.orderingToOrdered
     |   def compare(that: DeviceKey): Int =
     |      (this.serialNum, this.eventDate, this.EventTs * -1) compare
     |      (that.serialNum, that.eventDate, that.EventTs * -1)
     | }
defined class DeviceKey

scala>

scala> val t = sc.parallelize(List(((DeviceKey("2","100",1),1)),
(DeviceKey("2","100",3),1)), 1)
t: org.apache.spark.rdd.RDD[(DeviceKey, Int)] = ParallelCollectionRDD[0] at 
parallelize at <console>:26

scala>

scala> class DeviceKeyPartitioner(partitions: Int) extends 
org.apache.spark.Partitioner {
     |     require(partitions >= 0, s"Number of partitions ($partitions) cannot 
be negative.")
     |
     |     override def numPartitions: Int = partitions
     |
     |     override def getPartition(key: Any): Int = {
     |       val k = key.asInstanceOf[DeviceKey]
     |       k.serialNum.hashCode() % numPartitions
     |     }
     | }
defined class DeviceKeyPartitioner

scala>

scala> t.repartitionAndSortWithinPartitions(new DeviceKeyPartitioner(2))
res0: org.apache.spark.rdd.RDD[(DeviceKey, Int)] = ShuffledRDD[1] at 
repartitionAndSortWithinPartitions at <console>:30


Yong


________________________________
From: Pariksheet Barapatre <pbarapa...@gmail.com>
Sent: Wednesday, March 29, 2017 9:02 AM
To: user
Subject: Secondary Sort using Apache Spark 1.6

Hi,<http://stackoverflow.com/questions/43038682/secondary-sort-using-apache-spark-1-6#>

I am referring web link http://codingjunkie.net/spark-secondary-sort/ to 
implement secondary sort in my spark job.

I have defined my key case class as

case class DeviceKey(serialNum: String, eventDate: String, EventTs: Long) {
      implicit def orderingBySerialNum[A <: DeviceKey] : Ordering[A] = {
       Ordering.by(fk => (fk.serialNum, fk.eventDate, fk.EventTs * -1))
    }
}


but when I try to apply function
t.repartitionAndSortWithinPartitions(partitioner)


#t is a RDD[(DeviceKey, Int)]


I get error
I am getting error as -
value repartitionAndSortWithinPartitions is not a member of 
org.apache.spark.rdd.RDD[(DeviceKey, Int)]



Example code available at
http://stackoverflow.com/questions/43038682/secondary-sort-using-apache-spark-1-6


Could somebody help me to understand error.


Many Thanks

Pari

--
Cheers,
Pari

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