Spliterators.AbstractDoubleSpliterator

public static abstract class Spliterators.AbstractDoubleSpliterator extends Object
implements Spliterator.OfDouble

An abstract Spliterator.OfDouble that implements trySplit to permit limited parallelism.

To implement a spliterator an extending class need only implement Spliterator.OfDouble.tryAdvance(java.util.function.DoubleConsumer) tryAdvance}. The extending class should override Spliterator.OfDouble.forEachRemaining(java.util.function.DoubleConsumer) forEach} if it can provide a more performant implementation.

Inherited Constant Summary

Protected Constructor Summary

AbstractDoubleSpliterator(long est, int additionalCharacteristics)
Creates a spliterator reporting the given estimated size and characteristics.

Public Method Summary

int
characteristics()
Returns a set of characteristics of this Spliterator and its elements.
long
estimateSize()
Returns an estimate of the number of elements that would be encountered by a forEachRemaining(Consumer) traversal, or returns Long.MAX_VALUE if infinite, unknown, or too expensive to compute.
Spliterator.OfDouble
trySplit()
If this spliterator can be partitioned, returns a Spliterator covering elements, that will, upon return from this method, not be covered by this Spliterator. This implementation permits limited parallelism.

Inherited Method Summary

Protected Constructors

protected AbstractDoubleSpliterator (long est, int additionalCharacteristics)

Creates a spliterator reporting the given estimated size and characteristics.

Parameters
est the estimated size of this spliterator if known, otherwise Long.MAX_VALUE.
additionalCharacteristics properties of this spliterator's source or elements. If SIZED is reported then this spliterator will additionally report SUBSIZED.

Public Methods

public int characteristics ()

Returns a set of characteristics of this Spliterator and its elements. The result is represented as ORed values from ORDERED, DISTINCT, SORTED, SIZED, NONNULL, IMMUTABLE, CONCURRENT, SUBSIZED. Repeated calls to characteristics() on a given spliterator, prior to or in-between calls to trySplit, should always return the same result.

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.

Returns
  • a representation of characteristics

public long estimateSize ()

Returns an estimate of the number of elements that would be encountered by a forEachRemaining(Consumer) traversal, or returns Long.MAX_VALUE if infinite, unknown, or too expensive to compute.

If this Spliterator is SIZED and has not yet been partially traversed or split, or this Spliterator is 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 trySplit().

Returns
  • the estimated size, or Long.MAX_VALUE if infinite, unknown, or too expensive to compute.

public Spliterator.OfDouble trySplit ()

If this spliterator can be partitioned, returns a Spliterator covering elements, that will, upon return from this method, not be covered by this Spliterator.

If this Spliterator is ORDERED, the returned Spliterator must cover a strict prefix of the elements.

Unless this Spliterator covers an infinite number of elements, repeated calls to trySplit() must eventually return null. Upon non-null return:

  • the value reported for estimateSize() before splitting, must, after splitting, be greater than or equal to estimateSize() for this and the returned Spliterator; and
  • if this Spliterator is SUBSIZED, then estimateSize() for this spliterator before splitting must be equal to the sum of estimateSize() for this and the returned Spliterator after splitting.

This method may return null for any reason, including emptiness, inability to split after traversal has commenced, data structure constraints, and efficiency considerations. This implementation permits limited parallelism.

Returns
  • a Spliterator covering some portion of the elements, or null if this spliterator cannot be split