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	/*
	* Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
	* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
	*
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	*
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	*
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	package java.util;

	import java.util.function.Consumer;
	import java.util.function.DoubleConsumer;
	import java.util.function.IntConsumer;
	import java.util.function.LongConsumer;

	/**
	* An object for traversing and partitioning elements of a source. The source
	* of elements covered by a Spliterator could be, for example, an array, a
	* {@link Collection}, an IO channel, or a generator function.
	*
	* <p>A Spliterator may traverse elements individually ({@link
	* #tryAdvance tryAdvance()}) or sequentially in bulk
	* ({@link #forEachRemaining forEachRemaining()}).
	*
	* <p>A Spliterator may also partition off some of its elements (using
	* {@link #trySplit}) as another Spliterator, to be used in
	* possibly-parallel operations. Operations using a Spliterator that
	* cannot split, or does so in a highly imbalanced or inefficient
	* manner, are unlikely to benefit from parallelism. Traversal
	* and splitting exhaust elements; each Spliterator is useful for only a single
	* bulk computation.
	*
	* <p>A Spliterator also reports a set of {@link #characteristics()} of its
	* structure, source, and elements from among {@link #ORDERED},
	* {@link #DISTINCT}, {@link #SORTED}, {@link #SIZED}, {@link #NONNULL},
	* {@link #IMMUTABLE}, {@link #CONCURRENT}, and {@link #SUBSIZED}. These may
	* be employed by Spliterator clients to control, specialize or simplify
	* computation. For example, a Spliterator for a {@link Collection} would
	* report {@code SIZED}, a Spliterator for a {@link Set} would report
	* {@code DISTINCT}, and a Spliterator for a {@link SortedSet} would also
	* report {@code SORTED}. Characteristics are reported as a simple unioned bit
	* set.
	*
	* Some characteristics additionally constrain method behavior; for example if
	* {@code ORDERED}, traversal methods must conform to their documented ordering.
	* New characteristics may be defined in the future, so implementors should not
	* assign meanings to unlisted values.
	*
	* <p><a id="binding">A Spliterator that does not report {@code IMMUTABLE} or
	* {@code CONCURRENT} is expected to have a documented policy concerning:
	* when the spliterator <em>binds</em> to the element source; and detection of
	* structural interference of the element source detected after binding.</a> A
	* <em>late-binding</em> Spliterator binds to the source of elements at the
	* point of first traversal, first split, or first query for estimated size,
	* rather than at the time the Spliterator is created. A Spliterator that is
	* not <em>late-binding</em> binds to the source of elements at the point of
	* construction or first invocation of any method. Modifications made to the
	* source prior to binding are reflected when the Spliterator is traversed.
	* After binding a Spliterator should, on a best-effort basis, throw
	* {@link ConcurrentModificationException} if structural interference is
	* detected. Spliterators that do this are called <em>fail-fast</em>. The
	* bulk traversal method ({@link #forEachRemaining forEachRemaining()}) of a
	* Spliterator may optimize traversal and check for structural interference
	* after all elements have been traversed, rather than checking per-element and
	* failing immediately.
	*
	* <p>Spliterators can provide an estimate of the number of remaining elements
	* via the {@link #estimateSize} method. Ideally, as reflected in characteristic
	* {@link #SIZED}, this value corresponds exactly to the number of elements
	* that would be encountered in a successful traversal. However, even when not
	* exactly known, an estimated value may still be useful to operations
	* being performed on the source, such as helping to determine whether it is
	* preferable to split further or traverse the remaining elements sequentially.
	*
	* <p>Despite their obvious utility in parallel algorithms, spliterators are not
	* expected to be thread-safe; instead, implementations of parallel algorithms
	* using spliterators should ensure that the spliterator is only used by one
	* thread at a time. This is generally easy to attain via <em>serial
	* thread-confinement</em>, which often is a natural consequence of typical
	* parallel algorithms that work by recursive decomposition. A thread calling
	* {@link #trySplit()} may hand over the returned Spliterator to another thread,
	* which in turn may traverse or further split that Spliterator. The behaviour
	* of splitting and traversal is undefined if two or more threads operate
	* concurrently on the same spliterator. If the original thread hands a
	* spliterator off to another thread for processing, it is best if that handoff
	* occurs before any elements are consumed with {@link #tryAdvance(Consumer)
	* tryAdvance()}, as certain guarantees (such as the accuracy of
	* {@link #estimateSize()} for {@code SIZED} spliterators) are only valid before
	* traversal has begun.
	*
	* <p>Primitive subtype specializations of {@code Spliterator} are provided for
	* {@link OfInt int}, {@link OfLong long}, and {@link OfDouble double} values.
	* The subtype default implementations of
	* {@link Spliterator#tryAdvance(java.util.function.Consumer)}
	* and {@link Spliterator#forEachRemaining(java.util.function.Consumer)} box
	* primitive values to instances of their corresponding wrapper class. Such
	* boxing may undermine any performance advantages gained by using the primitive
	* specializations. To avoid boxing, the corresponding primitive-based methods
	* should be used. For example,
	* {@link Spliterator.OfInt#tryAdvance(java.util.function.IntConsumer)}
	* and {@link Spliterator.OfInt#forEachRemaining(java.util.function.IntConsumer)}
	* should be used in preference to
	* {@link Spliterator.OfInt#tryAdvance(java.util.function.Consumer)} and
	* {@link Spliterator.OfInt#forEachRemaining(java.util.function.Consumer)}.
	* Traversal of primitive values using boxing-based methods
	* {@link #tryAdvance tryAdvance()} and
	* {@link #forEachRemaining(java.util.function.Consumer) forEachRemaining()}
	* does not affect the order in which the values, transformed to boxed values,
	* are encountered.
	*
	* @apiNote
	* <p>Spliterators, like {@code Iterator}s, are for traversing the elements of
	* a source. The {@code Spliterator} API was designed to support efficient
	* parallel traversal in addition to sequential traversal, by supporting
	* decomposition as well as single-element iteration. In addition, the
	* protocol for accessing elements via a Spliterator is designed to impose
	* smaller per-element overhead than {@code Iterator}, and to avoid the inherent
	* race involved in having separate methods for {@code hasNext()} and
	* {@code next()}.
	*
	* <p>For mutable sources, arbitrary and non-deterministic behavior may occur if
	* the source is structurally interfered with (elements added, replaced, or
	* removed) between the time that the Spliterator binds to its data source and
	* the end of traversal. For example, such interference will produce arbitrary,
	* non-deterministic results when using the {@code java.util.stream} framework.
	*
	* <p>Structural interference of a source can be managed in the following ways
	* (in approximate order of decreasing desirability):
	* <ul>
	* <li>The source cannot be structurally interfered with.
	* <br>For example, an instance of
	* {@link java.util.concurrent.CopyOnWriteArrayList} is an immutable source.
	* A Spliterator created from the source reports a characteristic of
	* {@code IMMUTABLE}.</li>
	* <li>The source manages concurrent modifications.
	* <br>For example, a key set of a {@link java.util.concurrent.ConcurrentHashMap}
	* is a concurrent source. A Spliterator created from the source reports a
	* characteristic of {@code CONCURRENT}.</li>
	* <li>The mutable source provides a late-binding and fail-fast Spliterator.
	* <br>Late binding narrows the window during which interference can affect
	* the calculation; fail-fast detects, on a best-effort basis, that structural
	* interference has occurred after traversal has commenced and throws
	* {@link ConcurrentModificationException}. For example, {@link ArrayList},
	* and many other non-concurrent {@code Collection} classes in the JDK, provide
	* a late-binding, fail-fast spliterator.</li>
	* <li>The mutable source provides a non-late-binding but fail-fast Spliterator.
	* <br>The source increases the likelihood of throwing
	* {@code ConcurrentModificationException} since the window of potential
	* interference is larger.</li>
	* <li>The mutable source provides a late-binding and non-fail-fast Spliterator.
	* <br>The source risks arbitrary, non-deterministic behavior after traversal
	* has commenced since interference is not detected.
	* </li>
	* <li>The mutable source provides a non-late-binding and non-fail-fast
	* Spliterator.
	* <br>The source increases the risk of arbitrary, non-deterministic behavior
	* since non-detected interference may occur after construction.
	* </li>
	* </ul>
	*
	* <p><b>Example.</b> Here is a class (not a very useful one, except
	* for illustration) that maintains an array in which the actual data
	* are held in even locations, and unrelated tag data are held in odd
	* locations. Its Spliterator ignores the tags.
	*
	* <pre> {@code
	* class TaggedArray<T> {
	* private final Object[] elements; // immutable after construction
	* TaggedArray(T[] data, Object[] tags) {
	* int size = data.length;
	* if (tags.length != size) throw new IllegalArgumentException();
	* this.elements = new Object[2 * size];
	* for (int i = 0, j = 0; i < size; ++i) {
	* elements[j++] = data[i];
	* elements[j++] = tags[i];
	* }
	* }
	*
	* public Spliterator<T> spliterator() {
	* return new TaggedArraySpliterator<>(elements, 0, elements.length);
	* }
	*
	* static class TaggedArraySpliterator<T> implements Spliterator<T> {
	* private final Object[] array;
	* private int origin; // current index, advanced on split or traversal
	* private final int fence; // one past the greatest index
	*
	* TaggedArraySpliterator(Object[] array, int origin, int fence) {
	* this.array = array; this.origin = origin; this.fence = fence;
	* }
	*
	* public void forEachRemaining(Consumer<? super T> action) {
	* for (; origin < fence; origin += 2)
	* action.accept((T) array[origin]);
	* }
	*
	* public boolean tryAdvance(Consumer<? super T> action) {
	* if (origin < fence) {
	* action.accept((T) array[origin]);
	* origin += 2;
	* return true;
	* }
	* else // cannot advance
	* return false;
	* }
	*
	* public Spliterator<T> trySplit() {
	* int lo = origin; // divide range in half
	* int mid = ((lo + fence) >>> 1) & ~1; // force midpoint to be even
	* if (lo < mid) { // split out left half
	* origin = mid; // reset this Spliterator's origin
	* return new TaggedArraySpliterator<>(array, lo, mid);
	* }
	* else // too small to split
	* return null;
	* }
	*
	* public long estimateSize() {
	* return (long)((fence - origin) / 2);
	* }
	*
	* public int characteristics() {
	* return ORDERED \| SIZED \| IMMUTABLE \| SUBSIZED;
	* }
	* }
	* }}</pre>
	*
	* <p>As an example how a parallel computation framework, such as the
	* {@code java.util.stream} package, would use Spliterator in a parallel
	* computation, here is one way to implement an associated parallel forEach,
	* that illustrates the primary usage idiom of splitting off subtasks until
	* the estimated amount of work is small enough to perform
	* sequentially. Here we assume that the order of processing across
	* subtasks doesn't matter; different (forked) tasks may further split
	* and process elements concurrently in undetermined order. This
	* example uses a {@link java.util.concurrent.CountedCompleter};
	* similar usages apply to other parallel task constructions.
	*
	* <pre>{@code
	* static <T> void parEach(TaggedArray<T> a, Consumer<T> action) {
	* Spliterator<T> s = a.spliterator();
	* long targetBatchSize = s.estimateSize() / (ForkJoinPool.getCommonPoolParallelism() * 8);
	* new ParEach(null, s, action, targetBatchSize).invoke();
	* }
	*
	* static class ParEach<T> extends CountedCompleter<Void> {
	* final Spliterator<T> spliterator;
	* final Consumer<T> action;
	* final long targetBatchSize;
	*
	* ParEach(ParEach<T> parent, Spliterator<T> spliterator,
	* Consumer<T> action, long targetBatchSize) {
	* super(parent);
	* this.spliterator = spliterator; this.action = action;
	* this.targetBatchSize = targetBatchSize;
	* }
	*
	* public void compute() {
	* Spliterator<T> sub;
	* while (spliterator.estimateSize() > targetBatchSize &&
	* (sub = spliterator.trySplit()) != null) {
	* addToPendingCount(1);
	* new ParEach<>(this, sub, action, targetBatchSize).fork();
	* }
	* spliterator.forEachRemaining(action);
	* propagateCompletion();
	* }
	* }}</pre>
	*
	* @implNote
	* If the boolean system property {@code org.openjdk.java.util.stream.tripwire}
	* is set to {@code true} then diagnostic warnings are reported if boxing of
	* primitive values occur when operating on primitive subtype specializations.
	*
	* @param <T> the type of elements returned by this Spliterator
	*
	* @see Collection
	* @since 1.8
	*/
	public interface Spliterator<T> {
	/**
	* If a remaining element exists, performs the given action on it,
	* returning {@code true}; else returns {@code false}. If this
	* Spliterator is {@link #ORDERED} the action is performed on the
	* next element in encounter order. Exceptions thrown by the
	* action are relayed to the caller.
	*
	* @param action The action
	* @return {@code false} if no remaining elements existed
	* upon entry to this method, else {@code true}.
	* @throws NullPointerException if the specified action is null
	*/
	boolean tryAdvance(Consumer<? super T> action);

	/**
	* Performs the given action for each remaining element, sequentially in
	* the current thread, until all elements have been processed or the action
	* throws an exception. If this Spliterator is {@link #ORDERED}, actions
	* are performed in encounter order. Exceptions thrown by the action
	* are relayed to the caller.
	*
	* @implSpec
	* The default implementation repeatedly invokes {@link #tryAdvance} until
	* it returns {@code false}. It should be overridden whenever possible.
	*
	* @param action The action
	* @throws NullPointerException if the specified action is null
	*/
	default void forEachRemaining(Consumer<? super T> action) {
	do { } while (tryAdvance(action));
	}

	/**
	* If this spliterator can be partitioned, returns a Spliterator
	* covering elements, that will, upon return from this method, not
	* be covered by this Spliterator.
	*
	* <p>If this Spliterator is {@link #ORDERED}, the returned Spliterator
	* must cover a strict prefix of the elements.
	*
	* <p>Unless this Spliterator covers an infinite number of elements,
	* repeated calls to {@code trySplit()} must eventually return {@code null}.
	* Upon non-null return:
	* <ul>
	* <li>the value reported for {@code estimateSize()} before splitting,
	* must, after splitting, be greater than or equal to {@code estimateSize()}
	* for this and the returned Spliterator; and</li>
	* <li>if this Spliterator is {@code SUBSIZED}, then {@code estimateSize()}
	* for this spliterator before splitting must be equal to the sum of
	* {@code estimateSize()} for this and the returned Spliterator after
	* splitting.</li>
	* </ul>
	*
	* <p>This method may return {@code null} for any reason,
	* including emptiness, inability to split after traversal has
	* commenced, data structure constraints, and efficiency
	* considerations.
	*
	* @apiNote
	* An ideal {@code trySplit} method efficiently (without
	* traversal) divides its elements exactly in half, allowing
	* balanced parallel computation. Many departures from this ideal
	* remain highly effective; for example, only approximately
	* splitting an approximately balanced tree, or for a tree in
	* which leaf nodes may contain either one or two elements,
	* failing to further split these nodes. However, large
	* deviations in balance and/or overly inefficient {@code
	* trySplit} mechanics typically result in poor parallel
	* performance.
	*
	* @return a {@code Spliterator} covering some portion of the
	* elements, or {@code null} if this spliterator cannot be split
	*/
	Spliterator<T> trySplit();

	/**
	* Returns an estimate of the number of elements that would be
	* encountered by a {@link #forEachRemaining} traversal, or returns {@link
	* Long#MAX_VALUE} if infinite, unknown, or too expensive to compute.
	*
	* <p>If this Spliterator is {@link #SIZED} and has not yet been partially
	* traversed or split, or this Spliterator is {@link #SUBSIZED} and has
	* not yet been partially traversed, this estimate must be an accurate
	* count of elements that would be encountered by a complete traversal.
	* Otherwise, this estimate may be arbitrarily inaccurate, but must decrease
	* as specified across invocations of {@link #trySplit}.
	*
	* @apiNote
	* Even an inexact estimate is often useful and inexpensive to compute.
	* For example, a sub-spliterator of an approximately balanced binary tree
	* may return a value that estimates the number of elements to be half of
	* that of its parent; if the root Spliterator does not maintain an
	* accurate count, it could estimate size to be the power of two
	* corresponding to its maximum depth.
	*
	* @return the estimated size, or {@code Long.MAX_VALUE} if infinite,
	* unknown, or too expensive to compute.
	*/
	long estimateSize();

	/**
	* Convenience method that returns {@link #estimateSize()} if this
	* Spliterator is {@link #SIZED}, else {@code -1}.
	* @implSpec
	* The default implementation returns the result of {@code estimateSize()}
	* if the Spliterator reports a characteristic of {@code SIZED}, and
	* {@code -1} otherwise.
	*
	* @return the exact size, if known, else {@code -1}.
	*/
	default long getExactSizeIfKnown() {
	return (characteristics() & SIZED) == 0 ? -1L : estimateSize();
	}

	/**
	* Returns a set of characteristics of this Spliterator and its
	* elements. The result is represented as ORed values from {@link
	* #ORDERED}, {@link #DISTINCT}, {@link #SORTED}, {@link #SIZED},
	* {@link #NONNULL}, {@link #IMMUTABLE}, {@link #CONCURRENT},
	* {@link #SUBSIZED}. Repeated calls to {@code characteristics()} on
	* a given spliterator, prior to or in-between calls to {@code trySplit},
	* should always return the same result.
	*
	* <p>If a Spliterator reports an inconsistent set of
	* characteristics (either those returned from a single invocation
	* or across multiple invocations), no guarantees can be made
	* about any computation using this Spliterator.
	*
	* @apiNote The characteristics of a given spliterator before splitting
	* may differ from the characteristics after splitting. For specific
	* examples see the characteristic values {@link #SIZED}, {@link #SUBSIZED}
	* and {@link #CONCURRENT}.
	*
	* @return a representation of characteristics
	*/
	int characteristics();

	/**
	* Returns {@code true} if this Spliterator's {@link
	* #characteristics} contain all of the given characteristics.
	*
	* @implSpec
	* The default implementation returns true if the corresponding bits
	* of the given characteristics are set.
	*
	* @param characteristics the characteristics to check for
	* @return {@code true} if all the specified characteristics are present,
	* else {@code false}
	*/
	default boolean hasCharacteristics(int characteristics) {
	return (characteristics() & characteristics) == characteristics;
	}

	/**
	* If this Spliterator's source is {@link #SORTED} by a {@link Comparator},
	* returns that {@code Comparator}. If the source is {@code SORTED} in
	* {@linkplain Comparable natural order}, returns {@code null}. Otherwise,
	* if the source is not {@code SORTED}, throws {@link IllegalStateException}.
	*
	* @implSpec
	* The default implementation always throws {@link IllegalStateException}.
	*
	* @return a Comparator, or {@code null} if the elements are sorted in the
	* natural order.
	* @throws IllegalStateException if the spliterator does not report
	* a characteristic of {@code SORTED}.
	*/
	default Comparator<? super T> getComparator() {
	throw new IllegalStateException();
	}

	/**
	* Characteristic value signifying that an encounter order is defined for
	* elements. If so, this Spliterator guarantees that method
	* {@link #trySplit} splits a strict prefix of elements, that method
	* {@link #tryAdvance} steps by one element in prefix order, and that
	* {@link #forEachRemaining} performs actions in encounter order.
	*
	* <p>A {@link Collection} has an encounter order if the corresponding
	* {@link Collection#iterator} documents an order. If so, the encounter
	* order is the same as the documented order. Otherwise, a collection does
	* not have an encounter order.
	*
	* @apiNote Encounter order is guaranteed to be ascending index order for
	* any {@link List}. But no order is guaranteed for hash-based collections
	* such as {@link HashSet}. Clients of a Spliterator that reports
	* {@code ORDERED} are expected to preserve ordering constraints in
	* non-commutative parallel computations.
	*/
	public static final int ORDERED = 0x00000010;

	/**
	* Characteristic value signifying that, for each pair of
	* encountered elements {@code x, y}, {@code !x.equals(y)}. This
	* applies for example, to a Spliterator based on a {@link Set}.
	*/
	public static final int DISTINCT = 0x00000001;

	/**
	* Characteristic value signifying that encounter order follows a defined
	* sort order. If so, method {@link #getComparator()} returns the associated
	* Comparator, or {@code null} if all elements are {@link Comparable} and
	* are sorted by their natural ordering.
	*
	* <p>A Spliterator that reports {@code SORTED} must also report
	* {@code ORDERED}.
	*
	* @apiNote The spliterators for {@code Collection} classes in the JDK that
	* implement {@link NavigableSet} or {@link SortedSet} report {@code SORTED}.
	*/
	public static final int SORTED = 0x00000004;

	/**
	* Characteristic value signifying that the value returned from
	* {@code estimateSize()} prior to traversal or splitting represents a
	* finite size that, in the absence of structural source modification,
	* represents an exact count of the number of elements that would be
	* encountered by a complete traversal.
	*
	* @apiNote Most Spliterators for Collections, that cover all elements of a
	* {@code Collection} report this characteristic. Sub-spliterators, such as
	* those for {@link HashSet}, that cover a sub-set of elements and
	* approximate their reported size do not.
	*/
	public static final int SIZED = 0x00000040;

	/**
	* Characteristic value signifying that the source guarantees that
	* encountered elements will not be {@code null}. (This applies,
	* for example, to most concurrent collections, queues, and maps.)
	*/
	public static final int NONNULL = 0x00000100;

	/**
	* Characteristic value signifying that the element source cannot be
	* structurally modified; that is, elements cannot be added, replaced, or
	* removed, so such changes cannot occur during traversal. A Spliterator
	* that does not report {@code IMMUTABLE} or {@code CONCURRENT} is expected
	* to have a documented policy (for example throwing
	* {@link ConcurrentModificationException}) concerning structural
	* interference detected during traversal.
	*/
	public static final int IMMUTABLE = 0x00000400;

	/**
	* Characteristic value signifying that the element source may be safely
	* concurrently modified (allowing additions, replacements, and/or removals)
	* by multiple threads without external synchronization. If so, the
	* Spliterator is expected to have a documented policy concerning the impact
	* of modifications during traversal.
	*
	* <p>A top-level Spliterator should not report both {@code CONCURRENT} and
	* {@code SIZED}, since the finite size, if known, may change if the source
	* is concurrently modified during traversal. Such a Spliterator is
	* inconsistent and no guarantees can be made about any computation using
	* that Spliterator. Sub-spliterators may report {@code SIZED} if the
	* sub-split size is known and additions or removals to the source are not
	* reflected when traversing.
	*
	* <p>A top-level Spliterator should not report both {@code CONCURRENT} and
	* {@code IMMUTABLE}, since they are mutually exclusive. Such a Spliterator
	* is inconsistent and no guarantees can be made about any computation using
	* that Spliterator. Sub-spliterators may report {@code IMMUTABLE} if
	* additions or removals to the source are not reflected when traversing.
	*
	* @apiNote Most concurrent collections maintain a consistency policy
	* guaranteeing accuracy with respect to elements present at the point of
	* Spliterator construction, but possibly not reflecting subsequent
	* additions or removals.
	*/
	public static final int CONCURRENT = 0x00001000;

	/**
	* Characteristic value signifying that all Spliterators resulting from
	* {@code trySplit()} will be both {@link #SIZED} and {@link #SUBSIZED}.
	* (This means that all child Spliterators, whether direct or indirect, will
	* be {@code SIZED}.)
	*
	* <p>A Spliterator that does not report {@code SIZED} as required by
	* {@code SUBSIZED} is inconsistent and no guarantees can be made about any
	* computation using that Spliterator.
	*
	* @apiNote Some spliterators, such as the top-level spliterator for an
	* approximately balanced binary tree, will report {@code SIZED} but not
	* {@code SUBSIZED}, since it is common to know the size of the entire tree
	* but not the exact sizes of subtrees.
	*/
	public static final int SUBSIZED = 0x00004000;

	/**
	* A Spliterator specialized for primitive values.
	*
	* @param <T> the type of elements returned by this Spliterator. The
	* type must be a wrapper type for a primitive type, such as {@code Integer}
	* for the primitive {@code int} type.
	* @param <T_CONS> the type of primitive consumer. The type must be a
	* primitive specialization of {@link java.util.function.Consumer} for
	* {@code T}, such as {@link java.util.function.IntConsumer} for
	* {@code Integer}.
	* @param <T_SPLITR> the type of primitive Spliterator. The type must be
	* a primitive specialization of Spliterator for {@code T}, such as
	* {@link Spliterator.OfInt} for {@code Integer}.
	*
	* @see Spliterator.OfInt
	* @see Spliterator.OfLong
	* @see Spliterator.OfDouble
	* @since 1.8
	*/
	public interface OfPrimitive<T, T_CONS, T_SPLITR extends Spliterator.OfPrimitive<T, T_CONS, T_SPLITR>>
	extends Spliterator<T> {
	@Override
	T_SPLITR trySplit();

	/**
	* If a remaining element exists, performs the given action on it,
	* returning {@code true}; else returns {@code false}. If this
	* Spliterator is {@link #ORDERED} the action is performed on the
	* next element in encounter order. Exceptions thrown by the
	* action are relayed to the caller.
	*
	* @param action The action
	* @return {@code false} if no remaining elements existed
	* upon entry to this method, else {@code true}.
	* @throws NullPointerException if the specified action is null
	*/
	@SuppressWarnings("overloads")
	boolean tryAdvance(T_CONS action);

	/**
	* Performs the given action for each remaining element, sequentially in
	* the current thread, until all elements have been processed or the
	* action throws an exception. If this Spliterator is {@link #ORDERED},
	* actions are performed in encounter order. Exceptions thrown by the
	* action are relayed to the caller.
	*
	* @implSpec
	* The default implementation repeatedly invokes {@link #tryAdvance}
	* until it returns {@code false}. It should be overridden whenever
	* possible.
	*
	* @param action The action
	* @throws NullPointerException if the specified action is null
	*/
	@SuppressWarnings("overloads")
	default void forEachRemaining(T_CONS action) {
	do { } while (tryAdvance(action));
	}
	}

	/**
	* A Spliterator specialized for {@code int} values.
	* @since 1.8
	*/
	public interface OfInt extends OfPrimitive<Integer, IntConsumer, OfInt> {

	@Override
	OfInt trySplit();

	@Override
	boolean tryAdvance(IntConsumer action);

	@Override
	default void forEachRemaining(IntConsumer action) {
	do { } while (tryAdvance(action));
	}

	/**
	* {@inheritDoc}
	* @implSpec
	* If the action is an instance of {@code IntConsumer} then it is cast
	* to {@code IntConsumer} and passed to
	* {@link #tryAdvance(java.util.function.IntConsumer)}; otherwise
	* the action is adapted to an instance of {@code IntConsumer}, by
	* boxing the argument of {@code IntConsumer}, and then passed to
	* {@link #tryAdvance(java.util.function.IntConsumer)}.
	*/
	@Override
	default boolean tryAdvance(Consumer<? super Integer> action) {
	if (action instanceof IntConsumer) {
	return tryAdvance((IntConsumer) action);
	}
	else {
	if (Tripwire.ENABLED)
	Tripwire.trip(getClass(),
	"{0} calling Spliterator.OfInt.tryAdvance((IntConsumer) action::accept)");
	return tryAdvance((IntConsumer) action::accept);
	}
	}

	/**
	* {@inheritDoc}
	* @implSpec
	* If the action is an instance of {@code IntConsumer} then it is cast
	* to {@code IntConsumer} and passed to
	* {@link #forEachRemaining(java.util.function.IntConsumer)}; otherwise
	* the action is adapted to an instance of {@code IntConsumer}, by
	* boxing the argument of {@code IntConsumer}, and then passed to
	* {@link #forEachRemaining(java.util.function.IntConsumer)}.
	*/
	@Override
	default void forEachRemaining(Consumer<? super Integer> action) {
	if (action instanceof IntConsumer) {
	forEachRemaining((IntConsumer) action);
	}
	else {
	if (Tripwire.ENABLED)
	Tripwire.trip(getClass(),
	"{0} calling Spliterator.OfInt.forEachRemaining((IntConsumer) action::accept)");
	forEachRemaining((IntConsumer) action::accept);
	}
	}
	}

	/**
	* A Spliterator specialized for {@code long} values.
	* @since 1.8
	*/
	public interface OfLong extends OfPrimitive<Long, LongConsumer, OfLong> {

	@Override
	OfLong trySplit();

	@Override
	boolean tryAdvance(LongConsumer action);

	@Override
	default void forEachRemaining(LongConsumer action) {
	do { } while (tryAdvance(action));
	}

	/**
	* {@inheritDoc}
	* @implSpec
	* If the action is an instance of {@code LongConsumer} then it is cast
	* to {@code LongConsumer} and passed to
	* {@link #tryAdvance(java.util.function.LongConsumer)}; otherwise
	* the action is adapted to an instance of {@code LongConsumer}, by
	* boxing the argument of {@code LongConsumer}, and then passed to
	* {@link #tryAdvance(java.util.function.LongConsumer)}.
	*/
	@Override
	default boolean tryAdvance(Consumer<? super Long> action) {
	if (action instanceof LongConsumer) {
	return tryAdvance((LongConsumer) action);
	}
	else {
	if (Tripwire.ENABLED)
	Tripwire.trip(getClass(),
	"{0} calling Spliterator.OfLong.tryAdvance((LongConsumer) action::accept)");
	return tryAdvance((LongConsumer) action::accept);
	}
	}

	/**
	* {@inheritDoc}
	* @implSpec
	* If the action is an instance of {@code LongConsumer} then it is cast
	* to {@code LongConsumer} and passed to
	* {@link #forEachRemaining(java.util.function.LongConsumer)}; otherwise
	* the action is adapted to an instance of {@code LongConsumer}, by
	* boxing the argument of {@code LongConsumer}, and then passed to
	* {@link #forEachRemaining(java.util.function.LongConsumer)}.
	*/
	@Override
	default void forEachRemaining(Consumer<? super Long> action) {
	if (action instanceof LongConsumer) {
	forEachRemaining((LongConsumer) action);
	}
	else {
	if (Tripwire.ENABLED)
	Tripwire.trip(getClass(),
	"{0} calling Spliterator.OfLong.forEachRemaining((LongConsumer) action::accept)");
	forEachRemaining((LongConsumer) action::accept);
	}
	}
	}

	/**
	* A Spliterator specialized for {@code double} values.
	* @since 1.8
	*/
	public interface OfDouble extends OfPrimitive<Double, DoubleConsumer, OfDouble> {

	@Override
	OfDouble trySplit();

	@Override
	boolean tryAdvance(DoubleConsumer action);

	@Override
	default void forEachRemaining(DoubleConsumer action) {
	do { } while (tryAdvance(action));
	}

	/**
	* {@inheritDoc}
	* @implSpec
	* If the action is an instance of {@code DoubleConsumer} then it is
	* cast to {@code DoubleConsumer} and passed to
	* {@link #tryAdvance(java.util.function.DoubleConsumer)}; otherwise
	* the action is adapted to an instance of {@code DoubleConsumer}, by
	* boxing the argument of {@code DoubleConsumer}, and then passed to
	* {@link #tryAdvance(java.util.function.DoubleConsumer)}.
	*/
	@Override
	default boolean tryAdvance(Consumer<? super Double> action) {
	if (action instanceof DoubleConsumer) {
	return tryAdvance((DoubleConsumer) action);
	}
	else {
	if (Tripwire.ENABLED)
	Tripwire.trip(getClass(),
	"{0} calling Spliterator.OfDouble.tryAdvance((DoubleConsumer) action::accept)");
	return tryAdvance((DoubleConsumer) action::accept);
	}
	}

	/**
	* {@inheritDoc}
	* @implSpec
	* If the action is an instance of {@code DoubleConsumer} then it is
	* cast to {@code DoubleConsumer} and passed to
	* {@link #forEachRemaining(java.util.function.DoubleConsumer)};
	* otherwise the action is adapted to an instance of
	* {@code DoubleConsumer}, by boxing the argument of
	* {@code DoubleConsumer}, and then passed to
	* {@link #forEachRemaining(java.util.function.DoubleConsumer)}.
	*/
	@Override
	default void forEachRemaining(Consumer<? super Double> action) {
	if (action instanceof DoubleConsumer) {
	forEachRemaining((DoubleConsumer) action);
	}
	else {
	if (Tripwire.ENABLED)
	Tripwire.trip(getClass(),
	"{0} calling Spliterator.OfDouble.forEachRemaining((DoubleConsumer) action::accept)");
	forEachRemaining((DoubleConsumer) action::accept);
	}
	}
	}
	}

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