org.apache.spark.rdd

Class CoGroupedRDD<K>

Object

org.apache.spark.rdd.RDD<scala.Tuple2<K,scala.collection.Iterable<?>[]>>

org.apache.spark.rdd.CoGroupedRDD<K>

All Implemented Interfaces:

java.io.Serializable

public class CoGroupedRDD<K>
extends RDD<scala.Tuple2<K,scala.collection.Iterable<?>[]>>

:: DeveloperApi :: An RDD that cogroups its parents. For each key k in parent RDDs, the resulting RDD contains a tuple with the list of values for that key.

param: rdds parent RDDs. param: part partitioner used to partition the shuffle output

See Also:

Serialized Form

Note:

This is an internal API. We recommend users use RDD.cogroup(...) instead of instantiating this directly.

Constructor Summary

Constructors

Constructor and Description
CoGroupedRDD(scala.collection.Seq<RDD<? extends scala.Product2<K,?>>> rdds, Partitioner part, scala.reflect.ClassTag<K> evidence$1)

Method Summary

Methods

Modifier and Type	Method and Description
void	clearDependencies() Clears the dependencies of this RDD.
scala.collection.Iterator<scala.Tuple2<K,scala.collection.Iterable<?>[]>>	compute(Partition s, TaskContext context) :: DeveloperApi :: Implemented by subclasses to compute a given partition.
scala.collection.Seq<Dependency<?>>	getDependencies() Implemented by subclasses to return how this RDD depends on parent RDDs.
Partition[]	getPartitions() Implemented by subclasses to return the set of partitions in this RDD.
scala.Some<Partitioner>	partitioner() Optionally overridden by subclasses to specify how they are partitioned.
scala.collection.Seq<RDD<? extends scala.Product2<K,?>>>	rdds()
CoGroupedRDD<K>	setSerializer(Serializer serializer) Set a serializer for this RDD's shuffle, or null to use the default (spark.serializer)

Methods inherited from class org.apache.spark.rdd.RDD

aggregate, cache, cartesian, checkpoint, coalesce, collect, collect, context, count, countApprox, countApproxDistinct, countApproxDistinct, countByValue, countByValueApprox, dependencies, distinct, distinct, doubleRDDToDoubleRDDFunctions, filter, first, flatMap, fold, foreach, foreachPartition, getCheckpointFile, getNumPartitions, getStorageLevel, glom, groupBy, groupBy, groupBy, id, intersection, intersection, intersection, isCheckpointed, isEmpty, iterator, keyBy, localCheckpoint, map, mapPartitions, mapPartitionsWithIndex, max, min, name, numericRDDToDoubleRDDFunctions, partitions, persist, persist, pipe, pipe, pipe, preferredLocations, randomSplit, rddToAsyncRDDActions, rddToOrderedRDDFunctions, rddToPairRDDFunctions, rddToSequenceFileRDDFunctions, reduce, repartition, sample, saveAsObjectFile, saveAsTextFile, saveAsTextFile, setName, sortBy, sparkContext, subtract, subtract, subtract, take, takeOrdered, takeSample, toDebugString, toJavaRDD, toLocalIterator, top, toString, treeAggregate, treeReduce, union, unpersist, zip, zipPartitions, zipPartitions, zipPartitions, zipPartitions, zipPartitions, zipPartitions, zipWithIndex, zipWithUniqueId

Methods inherited from class Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Detail

CoGroupedRDD

public CoGroupedRDD(scala.collection.Seq<RDD<? extends scala.Product2<K,?>>> rdds,
            Partitioner part,
            scala.reflect.ClassTag<K> evidence$1)

Method Detail

rdds

public scala.collection.Seq<RDD<? extends scala.Product2<K,?>>> rdds()

setSerializer

public CoGroupedRDD<K> setSerializer(Serializer serializer)

Set a serializer for this RDD's shuffle, or null to use the default (spark.serializer)

getDependencies

public scala.collection.Seq<Dependency<?>> getDependencies()

Description copied from class: RDD

Implemented by subclasses to return how this RDD depends on parent RDDs. This method will only be called once, so it is safe to implement a time-consuming computation in it.

Returns:

(undocumented)

getPartitions

public Partition[] getPartitions()

Description copied from class: RDD

Implemented by subclasses to return the set of partitions in this RDD. This method will only be called once, so it is safe to implement a time-consuming computation in it.

The partitions in this array must satisfy the following property: rdd.partitions.zipWithIndex.forall { case (partition, index) => partition.index == index }

Returns:

(undocumented)

partitioner

public scala.Some<Partitioner> partitioner()

Description copied from class: RDD

Optionally overridden by subclasses to specify how they are partitioned.

Overrides:

partitioner in class RDD<scala.Tuple2<K,scala.collection.Iterable<?>[]>>

compute

public scala.collection.Iterator<scala.Tuple2<K,scala.collection.Iterable<?>[]>> compute(Partition s,
                                                                                TaskContext context)

Description copied from class: RDD

:: DeveloperApi :: Implemented by subclasses to compute a given partition.

Specified by:

compute in class RDD<scala.Tuple2<K,scala.collection.Iterable<?>[]>>

Parameters:

s - (undocumented)

context - (undocumented)

Returns:

(undocumented)

clearDependencies

public void clearDependencies()

Description copied from class: RDD

Clears the dependencies of this RDD. This method must ensure that all references to the original parent RDDs are removed to enable the parent RDDs to be garbage collected. Subclasses of RDD may override this method for implementing their own cleaning logic. See UnionRDD for an example.