Module java.base

Package java.util

Class Spliterators

java.lang.Object

java.util.Spliterators

public final class Spliterators
extends Object

Static classes and methods for operating on or creating instances of Spliterator and its primitive specializations Spliterator.OfInt, Spliterator.OfLong, and Spliterator.OfDouble.

Since:

1.8

See Also:

• Spliterator

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Spliterators.AbstractDoubleSpliterator	An abstract Spliterator.OfDouble that implements trySplit to permit limited parallelism.
static class	Spliterators.AbstractIntSpliterator	An abstract Spliterator.OfInt that implements trySplit to permit limited parallelism.
static class	Spliterators.AbstractLongSpliterator	An abstract Spliterator.OfLong that implements trySplit to permit limited parallelism.
static class	Spliterators.AbstractSpliterator<T>	An abstract Spliterator that implements trySplit to permit limited parallelism.

Method Summary

Modifier and Type	Method	Description
static Spliterator.OfDouble	emptyDoubleSpliterator()	Creates an empty Spliterator.OfDouble
static Spliterator.OfInt	emptyIntSpliterator()	Creates an empty Spliterator.OfInt
static Spliterator.OfLong	emptyLongSpliterator()	Creates an empty Spliterator.OfLong
static <T> Spliterator<T>	emptySpliterator()	Creates an empty Spliterator
static PrimitiveIterator.OfDouble	iterator(Spliterator.OfDouble spliterator)	Creates an PrimitiveIterator.OfDouble from a Spliterator.OfDouble.
static PrimitiveIterator.OfInt	iterator(Spliterator.OfInt spliterator)	Creates an PrimitiveIterator.OfInt from a Spliterator.OfInt.
static PrimitiveIterator.OfLong	iterator(Spliterator.OfLong spliterator)	Creates an PrimitiveIterator.OfLong from a Spliterator.OfLong.
static <T> Iterator<T>	iterator(Spliterator<? extends T> spliterator)	Creates an Iterator from a Spliterator.
static Spliterator.OfDouble	spliterator(double[] array, int additionalCharacteristics)	Creates a Spliterator.OfDouble covering the elements of a given array, using a customized set of spliterator characteristics.
static Spliterator.OfDouble	spliterator(double[] array, int fromIndex, int toIndex, int additionalCharacteristics)	Creates a Spliterator.OfDouble covering a range of elements of a given array, using a customized set of spliterator characteristics.
static Spliterator.OfInt	spliterator(int[] array, int additionalCharacteristics)	Creates a Spliterator.OfInt covering the elements of a given array, using a customized set of spliterator characteristics.
static Spliterator.OfInt	spliterator(int[] array, int fromIndex, int toIndex, int additionalCharacteristics)	Creates a Spliterator.OfInt covering a range of elements of a given array, using a customized set of spliterator characteristics.
static Spliterator.OfLong	spliterator(long[] array, int additionalCharacteristics)	Creates a Spliterator.OfLong covering the elements of a given array, using a customized set of spliterator characteristics.
static Spliterator.OfLong	spliterator(long[] array, int fromIndex, int toIndex, int additionalCharacteristics)	Creates a Spliterator.OfLong covering a range of elements of a given array, using a customized set of spliterator characteristics.
static <T> Spliterator<T>	spliterator(Object[] array, int additionalCharacteristics)	Creates a Spliterator covering the elements of a given array, using a customized set of spliterator characteristics.
static <T> Spliterator<T>	spliterator(Object[] array, int fromIndex, int toIndex, int additionalCharacteristics)	Creates a Spliterator covering a range of elements of a given array, using a customized set of spliterator characteristics.
static <T> Spliterator<T>	spliterator(Collection<? extends T> c, int characteristics)	Creates a Spliterator using the given collection's iterator as the source of elements, and reporting its size as its initial size.
static <T> Spliterator<T>	spliterator(Iterator<? extends T> iterator, long size, int characteristics)	Creates a Spliterator using a given Iterator as the source of elements, and with a given initially reported size.
static Spliterator.OfDouble	spliterator(PrimitiveIterator.OfDouble iterator, long size, int characteristics)	Creates a Spliterator.OfDouble using a given DoubleStream.DoubleIterator as the source of elements, and with a given initially reported size.
static Spliterator.OfInt	spliterator(PrimitiveIterator.OfInt iterator, long size, int characteristics)	Creates a Spliterator.OfInt using a given IntStream.IntIterator as the source of elements, and with a given initially reported size.
static Spliterator.OfLong	spliterator(PrimitiveIterator.OfLong iterator, long size, int characteristics)	Creates a Spliterator.OfLong using a given LongStream.LongIterator as the source of elements, and with a given initially reported size.
static <T> Spliterator<T>	spliteratorUnknownSize(Iterator<? extends T> iterator, int characteristics)	Creates a Spliterator using a given Iterator as the source of elements, with no initial size estimate.
static Spliterator.OfDouble	spliteratorUnknownSize(PrimitiveIterator.OfDouble iterator, int characteristics)	Creates a Spliterator.OfDouble using a given DoubleStream.DoubleIterator as the source of elements, with no initial size estimate.
static Spliterator.OfInt	spliteratorUnknownSize(PrimitiveIterator.OfInt iterator, int characteristics)	Creates a Spliterator.OfInt using a given IntStream.IntIterator as the source of elements, with no initial size estimate.
static Spliterator.OfLong	spliteratorUnknownSize(PrimitiveIterator.OfLong iterator, int characteristics)	Creates a Spliterator.OfLong using a given LongStream.LongIterator as the source of elements, with no initial size estimate.

Methods declared in class java.lang.Object

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

Method Details

emptySpliterator

public static <T> Spliterator<T> emptySpliterator()

Creates an empty Spliterator

The empty spliterator reports Spliterator.SIZED and Spliterator.SUBSIZED. Calls to Spliterator.trySplit() always return null.

Type Parameters:

T - Type of elements

Returns:

An empty spliterator

emptyIntSpliterator

public static Spliterator.OfInt emptyIntSpliterator()

Creates an empty Spliterator.OfInt

The empty spliterator reports Spliterator.SIZED and Spliterator.SUBSIZED. Calls to Spliterator.trySplit() always return null.

Returns:

An empty spliterator

emptyLongSpliterator

public static Spliterator.OfLong emptyLongSpliterator()

Creates an empty Spliterator.OfLong

The empty spliterator reports Spliterator.SIZED and Spliterator.SUBSIZED. Calls to Spliterator.trySplit() always return null.

Returns:

An empty spliterator

emptyDoubleSpliterator

public static Spliterator.OfDouble emptyDoubleSpliterator()

Creates an empty Spliterator.OfDouble

The empty spliterator reports Spliterator.SIZED and Spliterator.SUBSIZED. Calls to Spliterator.trySplit() always return null.

Returns:

An empty spliterator

spliterator

public static <T> Spliterator<T> spliterator(Object[] array,
 int additionalCharacteristics)

Creates a Spliterator covering the elements of a given array, using a customized set of spliterator characteristics.

This method is provided as an implementation convenience for Spliterators which store portions of their elements in arrays, and need fine control over Spliterator characteristics. Most other situations in which a Spliterator for an array is needed should use Arrays.spliterator(Object[]).

The returned spliterator always reports the characteristics SIZED and SUBSIZED. The caller may provide additional characteristics for the spliterator to report; it is common to additionally specify IMMUTABLE and ORDERED.

Type Parameters:

T - Type of elements

Parameters:

array - The array, assumed to be unmodified during use

additionalCharacteristics - Additional spliterator characteristics of this spliterator's source or elements beyond SIZED and SUBSIZED which are always reported

Returns:

A spliterator for an array

Throws:

NullPointerException - if the given array is null

See Also:

• Arrays.spliterator(Object[])

spliterator

public static <T> Spliterator<T> spliterator(Object[] array,
 int fromIndex,
 int toIndex,
 int additionalCharacteristics)

Creates a Spliterator covering a range of elements of a given array, using a customized set of spliterator characteristics.

This method is provided as an implementation convenience for Spliterators which store portions of their elements in arrays, and need fine control over Spliterator characteristics. Most other situations in which a Spliterator for an array is needed should use Arrays.spliterator(Object[]).

The returned spliterator always reports the characteristics SIZED and SUBSIZED. The caller may provide additional characteristics for the spliterator to report; it is common to additionally specify IMMUTABLE and ORDERED.

Type Parameters:

T - Type of elements

Parameters:

array - The array, assumed to be unmodified during use

fromIndex - The least index (inclusive) to cover

toIndex - One past the greatest index to cover

additionalCharacteristics - Additional spliterator characteristics of this spliterator's source or elements beyond SIZED and SUBSIZED which are always reported

Returns:

A spliterator for an array

Throws:

NullPointerException - if the given array is null

ArrayIndexOutOfBoundsException - if fromIndex is negative, toIndex is less than fromIndex, or toIndex is greater than the array size

See Also:

• Arrays.spliterator(Object[], int, int)

spliterator

public static Spliterator.OfInt spliterator(int[] array,
 int additionalCharacteristics)

Creates a Spliterator.OfInt covering the elements of a given array, using a customized set of spliterator characteristics.

This method is provided as an implementation convenience for Spliterators which store portions of their elements in arrays, and need fine control over Spliterator characteristics. Most other situations in which a Spliterator for an array is needed should use Arrays.spliterator(int[]).

The returned spliterator always reports the characteristics SIZED and SUBSIZED. The caller may provide additional characteristics for the spliterator to report; it is common to additionally specify IMMUTABLE and ORDERED.

Parameters:

array - The array, assumed to be unmodified during use

additionalCharacteristics - Additional spliterator characteristics of this spliterator's source or elements beyond SIZED and SUBSIZED which are always reported

Returns:

A spliterator for an array

Throws:

NullPointerException - if the given array is null

See Also:

• Arrays.spliterator(int[])

spliterator

public static Spliterator.OfInt spliterator(int[] array,
 int fromIndex,
 int toIndex,
 int additionalCharacteristics)

Creates a Spliterator.OfInt covering a range of elements of a given array, using a customized set of spliterator characteristics.

This method is provided as an implementation convenience for Spliterators which store portions of their elements in arrays, and need fine control over Spliterator characteristics. Most other situations in which a Spliterator for an array is needed should use Arrays.spliterator(int[], int, int).

The returned spliterator always reports the characteristics SIZED and SUBSIZED. The caller may provide additional characteristics for the spliterator to report; it is common to additionally specify IMMUTABLE and ORDERED.

Parameters:

array - The array, assumed to be unmodified during use

fromIndex - The least index (inclusive) to cover

toIndex - One past the greatest index to cover

additionalCharacteristics - Additional spliterator characteristics of this spliterator's source or elements beyond SIZED and SUBSIZED which are always reported

Returns:

A spliterator for an array

Throws:

NullPointerException - if the given array is null

ArrayIndexOutOfBoundsException - if fromIndex is negative, toIndex is less than fromIndex, or toIndex is greater than the array size

See Also:

• Arrays.spliterator(int[], int, int)

spliterator

public static Spliterator.OfLong spliterator(long[] array,
 int additionalCharacteristics)

Creates a Spliterator.OfLong covering the elements of a given array, using a customized set of spliterator characteristics.

This method is provided as an implementation convenience for Spliterators which store portions of their elements in arrays, and need fine control over Spliterator characteristics. Most other situations in which a Spliterator for an array is needed should use Arrays.spliterator(long[]).

The returned spliterator always reports the characteristics SIZED and SUBSIZED. The caller may provide additional characteristics for the spliterator to report; it is common to additionally specify IMMUTABLE and ORDERED.

Parameters:

array - The array, assumed to be unmodified during use

additionalCharacteristics - Additional spliterator characteristics of this spliterator's source or elements beyond SIZED and SUBSIZED which are always reported

Returns:

A spliterator for an array

Throws:

NullPointerException - if the given array is null

See Also:

• Arrays.spliterator(long[])

spliterator

public static Spliterator.OfLong spliterator(long[] array,
 int fromIndex,
 int toIndex,
 int additionalCharacteristics)

Creates a Spliterator.OfLong covering a range of elements of a given array, using a customized set of spliterator characteristics.

This method is provided as an implementation convenience for Spliterators which store portions of their elements in arrays, and need fine control over Spliterator characteristics. Most other situations in which a Spliterator for an array is needed should use Arrays.spliterator(long[], int, int).

The returned spliterator always reports the characteristics SIZED and SUBSIZED. The caller may provide additional characteristics for the spliterator to report. (For example, if it is known the array will not be further modified, specify IMMUTABLE; if the array data is considered to have an encounter order, specify ORDERED). The method Arrays.spliterator(long[], int, int) can often be used instead, which returns a spliterator that reports SIZED, SUBSIZED, IMMUTABLE, and ORDERED.

Parameters:

array - The array, assumed to be unmodified during use

fromIndex - The least index (inclusive) to cover

toIndex - One past the greatest index to cover

additionalCharacteristics - Additional spliterator characteristics of this spliterator's source or elements beyond SIZED and SUBSIZED which are always reported

Returns:

A spliterator for an array

Throws:

NullPointerException - if the given array is null

ArrayIndexOutOfBoundsException - if fromIndex is negative, toIndex is less than fromIndex, or toIndex is greater than the array size

See Also:

• Arrays.spliterator(long[], int, int)

spliterator

public static Spliterator.OfDouble spliterator(double[] array,
 int additionalCharacteristics)

Creates a Spliterator.OfDouble covering the elements of a given array, using a customized set of spliterator characteristics.

This method is provided as an implementation convenience for Spliterators which store portions of their elements in arrays, and need fine control over Spliterator characteristics. Most other situations in which a Spliterator for an array is needed should use Arrays.spliterator(double[]).

The returned spliterator always reports the characteristics SIZED and SUBSIZED. The caller may provide additional characteristics for the spliterator to report; it is common to additionally specify IMMUTABLE and ORDERED.

Parameters:

array - The array, assumed to be unmodified during use

additionalCharacteristics - Additional spliterator characteristics of this spliterator's source or elements beyond SIZED and SUBSIZED which are always reported

Returns:

A spliterator for an array

Throws:

NullPointerException - if the given array is null

See Also:

• Arrays.spliterator(double[])

spliterator

public static Spliterator.OfDouble spliterator(double[] array,
 int fromIndex,
 int toIndex,
 int additionalCharacteristics)

Creates a Spliterator.OfDouble covering a range of elements of a given array, using a customized set of spliterator characteristics.

This method is provided as an implementation convenience for Spliterators which store portions of their elements in arrays, and need fine control over Spliterator characteristics. Most other situations in which a Spliterator for an array is needed should use Arrays.spliterator(double[], int, int).

The returned spliterator always reports the characteristics SIZED and SUBSIZED. The caller may provide additional characteristics for the spliterator to report. (For example, if it is known the array will not be further modified, specify IMMUTABLE; if the array data is considered to have an encounter order, specify ORDERED). The method Arrays.spliterator(long[], int, int) can often be used instead, which returns a spliterator that reports SIZED, SUBSIZED, IMMUTABLE, and ORDERED.

Parameters:

array - The array, assumed to be unmodified during use

fromIndex - The least index (inclusive) to cover

toIndex - One past the greatest index to cover

additionalCharacteristics - Additional spliterator characteristics of this spliterator's source or elements beyond SIZED and SUBSIZED which are always reported

Returns:

A spliterator for an array

Throws:

NullPointerException - if the given array is null

ArrayIndexOutOfBoundsException - if fromIndex is negative, toIndex is less than fromIndex, or toIndex is greater than the array size

See Also:

• Arrays.spliterator(double[], int, int)

spliterator

public static <T> Spliterator<T> spliterator(Collection<? extends T> c,
 int characteristics)

Creates a Spliterator using the given collection's iterator as the source of elements, and reporting its size as its initial size.

The spliterator is late-binding, inherits the fail-fast properties of the collection's iterator, and implements trySplit to permit limited parallelism.

Type Parameters:

T - Type of elements

Parameters:

c - The collection

characteristics - Characteristics of this spliterator's source or elements. The characteristics SIZED and SUBSIZED are additionally reported unless CONCURRENT is supplied.

Returns:

A spliterator from an iterator

Throws:

NullPointerException - if the given collection is null

spliterator

public static <T> Spliterator<T> spliterator(Iterator<? extends T> iterator,
 long size,
 int characteristics)

Creates a Spliterator using a given Iterator as the source of elements, and with a given initially reported size.

The spliterator is not late-binding, inherits the fail-fast properties of the iterator, and implements trySplit to permit limited parallelism.

Traversal of elements should be accomplished through the spliterator. The behaviour of splitting and traversal is undefined if the iterator is operated on after the spliterator is returned, or the initially reported size is not equal to the actual number of elements in the source.

Type Parameters:

T - Type of elements

Parameters:

iterator - The iterator for the source

size - The number of elements in the source, to be reported as initial estimateSize

characteristics - Characteristics of this spliterator's source or elements. The characteristics SIZED and SUBSIZED are additionally reported unless CONCURRENT is supplied.

Returns:

A spliterator from an iterator

Throws:

NullPointerException - if the given iterator is null

spliteratorUnknownSize

public static <T> Spliterator<T> spliteratorUnknownSize(Iterator<? extends T> iterator,
 int characteristics)

Creates a Spliterator using a given Iterator as the source of elements, with no initial size estimate.

The spliterator is not late-binding, inherits the fail-fast properties of the iterator, and implements trySplit to permit limited parallelism.

Traversal of elements should be accomplished through the spliterator. The behaviour of splitting and traversal is undefined if the iterator is operated on after the spliterator is returned.

Type Parameters:

T - Type of elements

Parameters:

iterator - The iterator for the source

characteristics - Characteristics of this spliterator's source or elements (SIZED and SUBSIZED, if supplied, are ignored and are not reported.)

Returns:

A spliterator from an iterator

Throws:

NullPointerException - if the given iterator is null

spliterator

public static Spliterator.OfInt spliterator(PrimitiveIterator.OfInt iterator,
 long size,
 int characteristics)

Creates a Spliterator.OfInt using a given IntStream.IntIterator as the source of elements, and with a given initially reported size.

The spliterator is not late-binding, inherits the fail-fast properties of the iterator, and implements trySplit to permit limited parallelism.

Traversal of elements should be accomplished through the spliterator. The behaviour of splitting and traversal is undefined if the iterator is operated on after the spliterator is returned, or the initially reported size is not equal to the actual number of elements in the source.

Parameters:

iterator - The iterator for the source

size - The number of elements in the source, to be reported as initial estimateSize.

characteristics - Characteristics of this spliterator's source or elements. The characteristics SIZED and SUBSIZED are additionally reported unless CONCURRENT is supplied.

Returns:

A spliterator from an iterator

Throws:

NullPointerException - if the given iterator is null

spliteratorUnknownSize

public static Spliterator.OfInt spliteratorUnknownSize(PrimitiveIterator.OfInt iterator,
 int characteristics)

Creates a Spliterator.OfInt using a given IntStream.IntIterator as the source of elements, with no initial size estimate.

The spliterator is not late-binding, inherits the fail-fast properties of the iterator, and implements trySplit to permit limited parallelism.

Traversal of elements should be accomplished through the spliterator. The behaviour of splitting and traversal is undefined if the iterator is operated on after the spliterator is returned.

Parameters:

iterator - The iterator for the source

characteristics - Characteristics of this spliterator's source or elements (SIZED and SUBSIZED, if supplied, are ignored and are not reported.)

Returns:

A spliterator from an iterator

Throws:

NullPointerException - if the given iterator is null

spliterator

public static Spliterator.OfLong spliterator(PrimitiveIterator.OfLong iterator,
 long size,
 int characteristics)

Creates a Spliterator.OfLong using a given LongStream.LongIterator as the source of elements, and with a given initially reported size.

The spliterator is not late-binding, inherits the fail-fast properties of the iterator, and implements trySplit to permit limited parallelism.

Traversal of elements should be accomplished through the spliterator. The behaviour of splitting and traversal is undefined if the iterator is operated on after the spliterator is returned, or the initially reported size is not equal to the actual number of elements in the source.

Parameters:

iterator - The iterator for the source

size - The number of elements in the source, to be reported as initial estimateSize.

characteristics - Characteristics of this spliterator's source or elements. The characteristics SIZED and SUBSIZED are additionally reported unless CONCURRENT is supplied.

Returns:

A spliterator from an iterator

Throws:

NullPointerException - if the given iterator is null

spliteratorUnknownSize

public static Spliterator.OfLong spliteratorUnknownSize(PrimitiveIterator.OfLong iterator,
 int characteristics)

Creates a Spliterator.OfLong using a given LongStream.LongIterator as the source of elements, with no initial size estimate.

The spliterator is not late-binding, inherits the fail-fast properties of the iterator, and implements trySplit to permit limited parallelism.

Traversal of elements should be accomplished through the spliterator. The behaviour of splitting and traversal is undefined if the iterator is operated on after the spliterator is returned.

Parameters:

iterator - The iterator for the source

characteristics - Characteristics of this spliterator's source or elements (SIZED and SUBSIZED, if supplied, are ignored and are not reported.)

Returns:

A spliterator from an iterator

Throws:

NullPointerException - if the given iterator is null

spliterator

public static Spliterator.OfDouble spliterator(PrimitiveIterator.OfDouble iterator,
 long size,
 int characteristics)

Creates a Spliterator.OfDouble using a given DoubleStream.DoubleIterator as the source of elements, and with a given initially reported size.

The spliterator is not late-binding, inherits the fail-fast properties of the iterator, and implements trySplit to permit limited parallelism.

Traversal of elements should be accomplished through the spliterator. The behaviour of splitting and traversal is undefined if the iterator is operated on after the spliterator is returned, or the initially reported size is not equal to the actual number of elements in the source.

Parameters:

iterator - The iterator for the source

size - The number of elements in the source, to be reported as initial estimateSize

characteristics - Characteristics of this spliterator's source or elements. The characteristics SIZED and SUBSIZED are additionally reported unless CONCURRENT is supplied.

Returns:

A spliterator from an iterator

Throws:

NullPointerException - if the given iterator is null

spliteratorUnknownSize

public static Spliterator.OfDouble spliteratorUnknownSize(PrimitiveIterator.OfDouble iterator,
 int characteristics)

Creates a Spliterator.OfDouble using a given DoubleStream.DoubleIterator as the source of elements, with no initial size estimate.

The spliterator is not late-binding, inherits the fail-fast properties of the iterator, and implements trySplit to permit limited parallelism.

Traversal of elements should be accomplished through the spliterator. The behaviour of splitting and traversal is undefined if the iterator is operated on after the spliterator is returned.

Parameters:

iterator - The iterator for the source

characteristics - Characteristics of this spliterator's source or elements (SIZED and SUBSIZED, if supplied, are ignored and are not reported.)

Returns:

A spliterator from an iterator

Throws:

NullPointerException - if the given iterator is null

iterator

public static <T> Iterator<T> iterator(Spliterator<? extends T> spliterator)

Creates an Iterator from a Spliterator.

Traversal of elements should be accomplished through the iterator. The behaviour of traversal is undefined if the spliterator is operated after the iterator is returned.

Type Parameters:

T - Type of elements

Parameters:

spliterator - The spliterator

Returns:

An iterator

Throws:

NullPointerException - if the given spliterator is null

iterator

public static PrimitiveIterator.OfInt iterator(Spliterator.OfInt spliterator)

Creates an PrimitiveIterator.OfInt from a Spliterator.OfInt.

Traversal of elements should be accomplished through the iterator. The behaviour of traversal is undefined if the spliterator is operated after the iterator is returned.

Parameters:

spliterator - The spliterator

Returns:

An iterator

Throws:

NullPointerException - if the given spliterator is null

iterator

public static PrimitiveIterator.OfLong iterator(Spliterator.OfLong spliterator)

Creates an PrimitiveIterator.OfLong from a Spliterator.OfLong.

Traversal of elements should be accomplished through the iterator. The behaviour of traversal is undefined if the spliterator is operated after the iterator is returned.

Parameters:

spliterator - The spliterator

Returns:

An iterator

Throws:

NullPointerException - if the given spliterator is null

iterator

public static PrimitiveIterator.OfDouble iterator(Spliterator.OfDouble spliterator)

Creates an PrimitiveIterator.OfDouble from a Spliterator.OfDouble.

Traversal of elements should be accomplished through the iterator. The behaviour of traversal is undefined if the spliterator is operated after the iterator is returned.

Parameters:

spliterator - The spliterator

Returns:

An iterator

Throws:

NullPointerException - if the given spliterator is null