org.apache.flink.util

Class SplittableIterator<T>

java.lang.Object

org.apache.flink.util.SplittableIterator<T>

Type Parameters:

T - The type of elements returned by the iterator.

All Implemented Interfaces:

Serializable, Iterator<T>

Direct Known Subclasses:

LongValueSequenceIterator, NumberSequenceIterator

@Public
public abstract class SplittableIterator<T>
extends Object
implements Iterator<T>, Serializable

Abstract base class for iterators that can split themselves into multiple disjoint iterators. The union of these iterators returns the original iterator values.

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
SplittableIterator()

Method Summary

Modifier and Type	Method and Description
abstract int	getMaximumNumberOfSplits() The maximum number of splits into which this iterator can be split up.
Iterator<T>	getSplit(int num, int numPartitions) Splits this iterator into n partitions and returns the i-th partition out of those.
abstract Iterator<T>[]	split(int numPartitions) Splits this iterator into a number disjoint iterators.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.Iterator

forEachRemaining, hasNext, next, remove

Constructor Detail

SplittableIterator

public SplittableIterator()

Method Detail

split

public abstract Iterator<T>[] split(int numPartitions)

Splits this iterator into a number disjoint iterators. The union of these iterators returns the original iterator values.

Parameters:

numPartitions - The number of iterators to split into.

Returns:

An array with the split iterators.

getSplit

public Iterator<T> getSplit(int num,
                            int numPartitions)

Splits this iterator into n partitions and returns the i-th partition out of those.

Parameters:

num - The partition to return (i).

numPartitions - The number of partitions to split into (n).

Returns:

The iterator for the partition.

getMaximumNumberOfSplits

public abstract int getMaximumNumberOfSplits()

The maximum number of splits into which this iterator can be split up.

Returns:

The maximum number of splits into which this iterator can be split up.