ParallelDoubleStreamSupport (Parallel Stream Support 1.0.0 API)

java.lang.Object
- com.github.ferstl.streams.ParallelDoubleStreamSupport

All Implemented Interfaces:

AutoCloseable, BaseStream<Double,DoubleStream>, DoubleStream
```
public class ParallelDoubleStreamSupport
extends Object
implements DoubleStream
```
An implementation of DoubleStream which uses a custom ForkJoinPool for parallel aggregate operations. This is the double primitive specialization of ParallelStreamSupport.
The following example illustrates an aggregate operation using ParallelStreamSupport and ParallelDoubleStreamSupport with a custom ForkJoinPool, computing the sum of the weights of the red widgets:
```
 ForkJoinPool pool = new ForkJoinPool();
 double sum = ParallelStreamSupport.parallelStream(widgets, pool)
     .filter(w -> w.getColor() == RED)
     .mapToDouble(w -> w.getWeight())
     .sum();
 
```
In case this stream is configured for parallel execution, i.e. isParallel() returns true, a terminal operation will be executed as ForkJoinTask in the custom ForkJoinPool. Otherwise it will be executed in the calling thread.
This implementation offers various factory methods which are based on:
- The static factory methods of DoubleStream, which are meaningful for parallel streams
- Arrays.stream(double[])
- StreamSupport.doubleStream(Spliterator.OfDouble, boolean)
- StreamSupport.doubleStream(Supplier, int, boolean)
API Note:

Internally, this stream wraps a double stream which is initially created in one of the static factory methods. Whenever a non-terminal operation is called the underlying stream will be replaced with the result of calling the same method on that stream. The return value of these operations is always this stream or, in case of operations that return a different type of stream, one of ParallelStreamSupport, ParallelIntStreamSupport or ParallelLongStreamSupport.

Although each factory method returns a parallel stream, calling sequential() is still possible and leads to sequential execution of a terminal operation within the calling thread.

Implementation Note:

See the class documentation for Stream and the package documentation for java.util.stream for additional specification.

Nested Class Summary
- Nested classes/interfaces inherited from interface java.util.stream.DoubleStream
  DoubleStream.Builder

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`boolean`	`allMatch(DoublePredicate predicate)` Returns whether all elements of this stream match the provided predicate.
`boolean`	`anyMatch(DoublePredicate predicate)` Returns whether any elements of this stream match the provided predicate.
`OptionalDouble`	`average()` Returns an `OptionalDouble` describing the arithmetic mean of elements of this stream, or an empty optional if this stream is empty.
`Stream<Double>`	`boxed()` Returns a `Stream` consisting of the elements of this stream, boxed to `Double`.
`void`	`close()` Closes this stream, causing all close handlers for this stream pipeline to be called.
`<R> R`	`collect(Supplier<R> supplier, ObjDoubleConsumer<R> accumulator, BiConsumer<R,R> combiner)` Performs a mutable reduction operation on the elements of this stream.
`static DoubleStream`	`concat(DoubleStream a, DoubleStream b, ForkJoinPool workerPool)` Creates a lazily concatenated parallel `double` stream whose elements are all the elements of the first stream followed by all the elements of the second stream.
`long`	`count()` Returns the count of elements in this stream.
`DoubleStream`	`distinct()` Returns a stream consisting of the distinct elements of this stream.
`protected <R> R`	`execute(Callable<R> terminalOperation)`
`protected void`	`execute(Runnable terminalOperation)`
`DoubleStream`	`filter(DoublePredicate predicate)` Returns a stream consisting of the elements of this stream that match the given predicate.
`OptionalDouble`	`findAny()` Returns an `OptionalDouble` describing some element of the stream, or an empty `OptionalDouble` if the stream is empty.
`OptionalDouble`	`findFirst()` Returns an `OptionalDouble` describing the first element of this stream, or an empty `OptionalDouble` if the stream is empty.
`DoubleStream`	`flatMap(DoubleFunction<? extends DoubleStream> mapper)` Returns a stream consisting of the results of replacing each element of this stream with the contents of a mapped stream produced by applying the provided mapping function to each element.
`void`	`forEach(DoubleConsumer action)` Performs an action for each element of this stream.
`void`	`forEachOrdered(DoubleConsumer action)` Performs an action for each element of this stream, guaranteeing that each element is processed in encounter order for streams that have a defined encounter order.
`static DoubleStream`	`generate(DoubleSupplier supplier, ForkJoinPool workerPool)` Creates a parallel infinite sequential unordered `double` stream where each element is generated by the provided `DoubleSupplier`.
`boolean`	`isParallel()` Returns whether this stream, if a terminal operation were to be executed, would execute in parallel.
`static DoubleStream`	`iterate(double seed, DoubleUnaryOperator operator, ForkJoinPool workerPool)` Creates a parallel infinite ordered `double` stream produced by iterative application of a function `f` to an initial element `seed`.
`PrimitiveIterator.OfDouble`	`iterator()` Returns an iterator for the elements of this stream.
`DoubleStream`	`limit(long maxSize)` Returns a stream consisting of the elements of this stream, truncated to be no longer than `maxSize` in length.
`DoubleStream`	`map(DoubleUnaryOperator mapper)` Returns a stream consisting of the results of applying the given function to the elements of this stream.
`IntStream`	`mapToInt(DoubleToIntFunction mapper)` Returns an `IntStream` consisting of the results of applying the given function to the elements of this stream.
`LongStream`	`mapToLong(DoubleToLongFunction mapper)` Returns a `LongStream` consisting of the results of applying the given function to the elements of this stream.
`<U> Stream<U>`	`mapToObj(DoubleFunction<? extends U> mapper)` Returns an object-valued `Stream` consisting of the results of applying the given function to the elements of this stream.
`OptionalDouble`	`max()` Returns an `OptionalDouble` describing the maximum element of this stream, or an empty OptionalDouble if this stream is empty.
`OptionalDouble`	`min()` Returns an `OptionalDouble` describing the minimum element of this stream, or an empty OptionalDouble if this stream is empty.
`boolean`	`noneMatch(DoublePredicate predicate)` Returns whether no elements of this stream match the provided predicate.
`S`	`onClose(Runnable closeHandler)` Returns an equivalent stream with an additional close handler.
`S`	`parallel()` Returns an equivalent stream that is parallel.
`static DoubleStream`	`parallelStream(double[] array, ForkJoinPool workerPool)` Creates a parallel `double` stream from the given Array.
`static DoubleStream`	`parallelStream(DoubleStream.Builder builder, ForkJoinPool workerPool)` Creates a parallel `double` stream from the given `Builder`.
`static DoubleStream`	`parallelStream(Spliterator.OfDouble spliterator, ForkJoinPool workerPool)` Creates a parallel `double` stream from the given Spliterator.
`static DoubleStream`	`parallelStream(Supplier<? extends Spliterator.OfDouble> supplier, int characteristics, ForkJoinPool workerPool)` Creates a parallel `double` stream from the given Spliterator supplier.
`DoubleStream`	`peek(DoubleConsumer action)` Returns a stream consisting of the elements of this stream, additionally performing the provided action on each element as elements are consumed from the resulting stream.
`OptionalDouble`	`reduce(DoubleBinaryOperator op)` Performs a reduction on the elements of this stream, using an associative accumulation function, and returns an `OptionalDouble` describing the reduced value, if any.
`double`	`reduce(double identity, DoubleBinaryOperator op)` Performs a reduction on the elements of this stream, using the provided identity value and an associative accumulation function, and returns the reduced value.
`S`	`sequential()` Returns an equivalent stream that is sequential.
`DoubleStream`	`skip(long n)` Returns a stream consisting of the remaining elements of this stream after discarding the first `n` elements of the stream.
`DoubleStream`	`sorted()` Returns a stream consisting of the elements of this stream in sorted order.
`Spliterator.OfDouble`	`spliterator()` Returns a spliterator for the elements of this stream.
`double`	`sum()` Returns the sum of elements in this stream.
`DoubleSummaryStatistics`	`summaryStatistics()` Returns a `DoubleSummaryStatistics` describing various summary data about the elements of this stream.
`double[]`	`toArray()` Returns an array containing the elements of this stream.
`S`	`unordered()` Returns an equivalent stream that is unordered.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface java.util.stream.DoubleStream
builder, concat, empty, generate, iterate, of, of, parallel, sequential

Methods inherited from interface java.util.stream.BaseStream
close, isParallel, onClose, unordered

- Method Detail
  - parallelStream
```
public static DoubleStream parallelStream(double[] array,
                                          ForkJoinPool workerPool)
```
    Creates a parallel double stream from the given Array. This operation is similar to calling Arrays.stream(array).parallel() with the difference that a parallel terminal operation will be executed in the given ForkJoinPool.
    
    Parameters:
    
    array - Array to create the parallel stream from. Must not be null.
    
    workerPool - Thread pool for parallel execution of a terminal operation. Must not be null.
    
    Returns:
    
    A parallel double stream that executes a terminal operation in the given ForkJoinPool.
    
    See Also:
    
    Arrays.stream(int[])
  - parallelStream
```
public static DoubleStream parallelStream(Spliterator.OfDouble spliterator,
                                          ForkJoinPool workerPool)
```
    Creates a parallel double stream from the given Spliterator. This operation is similar to calling StreamSupport.doubleStream(spliterator, true) with the difference that a parallel terminal operation will be executed in the given ForkJoinPool.
    
    Parameters:
    
    spliterator - A Spliterator.OfDouble describing the stream elements. Must not be null.
    
    workerPool - Thread pool for parallel execution of a terminal operation. Must not be null.
    
    Returns:
    
    A parallel double stream that executes a terminal operation in the given ForkJoinPool.
    
    See Also:
    
    StreamSupport.doubleStream(Spliterator.OfDouble, boolean)
  - parallelStream
```
public static DoubleStream parallelStream(Supplier<? extends Spliterator.OfDouble> supplier,
                                          int characteristics,
                                          ForkJoinPool workerPool)
```
    Creates a parallel double stream from the given Spliterator supplier. This operation is similar to calling StreamSupport.doubleStream(supplier, characteristics, true) with the difference that a parallel terminal operation will be executed in the given ForkJoinPool.
    
    Parameters:
    
    supplier - A Supplier of a Spliterator.OfDouble. Must not be null.
    
    characteristics - Spliterator characteristics of the supplied Spliterator. The characteristics must be equal to supplier.get().characteristics(), otherwise undefined behavior may occur when terminal operation commences.
    
    workerPool - Thread pool for parallel execution of a terminal operation. Must not be null.
    
    Returns:
    
    A parallel double stream that executes a terminal operation in the given ForkJoinPool.
    
    See Also:
    
    StreamSupport.doubleStream(Supplier, int, boolean)
  - parallelStream
```
public static DoubleStream parallelStream(DoubleStream.Builder builder,
                                          ForkJoinPool workerPool)
```
    Creates a parallel double stream from the given Builder. This operation is similar to calling builder.build().parallel() with the difference that a parallel terminal operation will be executed in the given ForkJoinPool.
    
    Parameters:
    
    builder - The builder to create the stream from. Must not be null.
    
    workerPool - Thread pool for parallel execution of a terminal operation. Must not be null.
    
    Returns:
    
    A parallel double stream that executes a terminal operation in the given ForkJoinPool.
    
    See Also:
    
    DoubleStream.builder()
  - iterate
```
public static DoubleStream iterate(double seed,
                                   DoubleUnaryOperator operator,
                                   ForkJoinPool workerPool)
```
    Creates a parallel infinite ordered double stream produced by iterative application of a function f to an initial element seed. This operation is similar to calling DoubleStream.iterate(seed, operator).parallel() with the difference that a parallel terminal operation will be executed in the given ForkJoinPool.
    
    Parameters:
    
    seed - The initial element.
    
    operator - A function to be applied to to the previous element to produce a new element. Must not be null.
    
    workerPool - Thread pool for parallel execution of a terminal operation. Must not be null.
    
    Returns:
    
    A parallel double stream that executes a terminal operation in the given ForkJoinPool.
    
    See Also:
    
    DoubleStream.iterate(double, DoubleUnaryOperator)
  - generate
```
public static DoubleStream generate(DoubleSupplier supplier,
                                    ForkJoinPool workerPool)
```
    Creates a parallel infinite sequential unordered double stream where each element is generated by the provided DoubleSupplier. This operation is similar to calling DoubleStream.generate(supplier).parallel() with the difference that a parallel terminal operation will be executed in the given ForkJoinPool.
    
    Parameters:
    
    supplier - The DoubleSupplier of generated elements. Must not be null.
    
    workerPool - Thread pool for parallel execution of a terminal operation. Must not be null.
    
    Returns:
    
    A parallel double stream that executes a terminal operation in the given ForkJoinPool.
    
    See Also:
    
    DoubleStream.generate(DoubleSupplier)
  - concat
```
public static DoubleStream concat(DoubleStream a,
                                  DoubleStream b,
                                  ForkJoinPool workerPool)
```
    Creates a lazily concatenated parallel double stream whose elements are all the elements of the first stream followed by all the elements of the second stream. This operation is similar to calling DoubleStream.concat(a, b).parallel() with the difference that a parallel terminal operation will be executed in the given ForkJoinPool.
    
    Parameters:
    
    a - The first stream. Must not be null.
    
    b - The second stream. Must not be null.
    
    workerPool - Thread pool for parallel execution of a terminal operation. Must not be null.
    
    Returns:
    
    A parallel stream that executes a terminal operation in the given ForkJoinPool.
    
    See Also:
    
    DoubleStream.concat(DoubleStream, DoubleStream)
  - filter
```
public DoubleStream filter(DoublePredicate predicate)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns a stream consisting of the elements of this stream that match the given predicate.
    This is an intermediate operation.
    
    Specified by:
    
    filter in interface DoubleStream
    
    Parameters:
    
    predicate - a non-interfering, stateless predicate to apply to each element to determine if it should be included
    
    Returns:
    
    the new stream
  - map
```
public DoubleStream map(DoubleUnaryOperator mapper)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns a stream consisting of the results of applying the given function to the elements of this stream.
    This is an intermediate operation.
    
    Specified by:
    
    map in interface DoubleStream
    
    Parameters:
    
    mapper - a non-interfering, stateless function to apply to each element
    
    Returns:
    
    the new stream
  - mapToObj
```
public <U> Stream<U> mapToObj(DoubleFunction<? extends U> mapper)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns an object-valued Stream consisting of the results of applying the given function to the elements of this stream.
    This is an intermediate operation.
    
    Specified by:
    
    mapToObj in interface DoubleStream
    
    Type Parameters:
    
    U - the element type of the new stream
    
    Parameters:
    
    mapper - a non-interfering, stateless function to apply to each element
    
    Returns:
    
    the new stream
  - mapToInt
```
public IntStream mapToInt(DoubleToIntFunction mapper)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns an IntStream consisting of the results of applying the given function to the elements of this stream.
    This is an intermediate operation.
    
    Specified by:
    
    mapToInt in interface DoubleStream
    
    Parameters:
    
    mapper - a non-interfering, stateless function to apply to each element
    
    Returns:
    
    the new stream
  - mapToLong
```
public LongStream mapToLong(DoubleToLongFunction mapper)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns a LongStream consisting of the results of applying the given function to the elements of this stream.
    This is an intermediate operation.
    
    Specified by:
    
    mapToLong in interface DoubleStream
    
    Parameters:
    
    mapper - a non-interfering, stateless function to apply to each element
    
    Returns:
    
    the new stream
  - flatMap
```
public DoubleStream flatMap(DoubleFunction<? extends DoubleStream> mapper)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns a stream consisting of the results of replacing each element of this stream with the contents of a mapped stream produced by applying the provided mapping function to each element. Each mapped stream is closed after its contents have been placed into this stream. (If a mapped stream is null an empty stream is used, instead.)
    This is an intermediate operation.
    
    Specified by:
    
    flatMap in interface DoubleStream
    
    Parameters:
    
    mapper - a non-interfering, stateless function to apply to each element which produces a DoubleStream of new values
    
    Returns:
    
    the new stream
    
    See Also:
    
    Stream.flatMap(Function)
  - distinct
```
public DoubleStream distinct()
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns a stream consisting of the distinct elements of this stream. The elements are compared for equality according to Double.compare(double, double).
    This is a stateful intermediate operation.
    
    Specified by:
    
    distinct in interface DoubleStream
    
    Returns:
    
    the result stream
  - sorted
```
public DoubleStream sorted()
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns a stream consisting of the elements of this stream in sorted order. The elements are compared for equality according to Double.compare(double, double).
    This is a stateful intermediate operation.
    
    Specified by:
    
    sorted in interface DoubleStream
    
    Returns:
    
    the result stream
  - peek
```
public DoubleStream peek(DoubleConsumer action)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns a stream consisting of the elements of this stream, additionally performing the provided action on each element as elements are consumed from the resulting stream.
    This is an intermediate operation.
    For parallel stream pipelines, the action may be called at whatever time and in whatever thread the element is made available by the upstream operation. If the action modifies shared state, it is responsible for providing the required synchronization.
    
    Specified by:
    
    peek in interface DoubleStream
    
    Parameters:
    
    action - a non-interfering action to perform on the elements as they are consumed from the stream
    
    Returns:
    
    the new stream
  - limit
```
public DoubleStream limit(long maxSize)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns a stream consisting of the elements of this stream, truncated to be no longer than maxSize in length.
    This is a short-circuiting stateful intermediate operation.
    
    Specified by:
    
    limit in interface DoubleStream
    
    Parameters:
    
    maxSize - the number of elements the stream should be limited to
    
    Returns:
    
    the new stream
  - skip
```
public DoubleStream skip(long n)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns a stream consisting of the remaining elements of this stream after discarding the first n elements of the stream. If this stream contains fewer than n elements then an empty stream will be returned.
    This is a stateful intermediate operation.
    
    Specified by:
    
    skip in interface DoubleStream
    
    Parameters:
    
    n - the number of leading elements to skip
    
    Returns:
    
    the new stream
  - forEach
```
public void forEach(DoubleConsumer action)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Performs an action for each element of this stream.
    This is a terminal operation.
    For parallel stream pipelines, this operation does not guarantee to respect the encounter order of the stream, as doing so would sacrifice the benefit of parallelism. For any given element, the action may be performed at whatever time and in whatever thread the library chooses. If the action accesses shared state, it is responsible for providing the required synchronization.
    
    Specified by:
    
    forEach in interface DoubleStream
    
    Parameters:
    
    action - a non-interfering action to perform on the elements
  - forEachOrdered
```
public void forEachOrdered(DoubleConsumer action)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Performs an action for each element of this stream, guaranteeing that each element is processed in encounter order for streams that have a defined encounter order.
    This is a terminal operation.
    
    Specified by:
    
    forEachOrdered in interface DoubleStream
    
    Parameters:
    
    action - a non-interfering action to perform on the elements
    
    See Also:
    
    DoubleStream.forEach(DoubleConsumer)
  - toArray
```
public double[] toArray()
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns an array containing the elements of this stream.
    This is a terminal operation.
    
    Specified by:
    
    toArray in interface DoubleStream
    
    Returns:
    
    an array containing the elements of this stream
  - reduce
```
public double reduce(double identity,
                     DoubleBinaryOperator op)
```
    Description copied from interface: java.util.stream.DoubleStream
    Performs a reduction on the elements of this stream, using the provided identity value and an associative accumulation function, and returns the reduced value. This is equivalent to:
```
     double result = identity;
     for (double element : this stream)
         result = accumulator.applyAsDouble(result, element)
     return result;
 
```
    but is not constrained to execute sequentially.
    The identity value must be an identity for the accumulator function. This means that for all x, accumulator.apply(identity, x) is equal to x. The accumulator function must be an associative function.
    This is a terminal operation.
    Specified by:
    
    reduce in interface DoubleStream
    
    Parameters:
    
    identity - the identity value for the accumulating function
    
    op - an associative, non-interfering, stateless function for combining two values
    
    Returns:
    
    the result of the reduction
    
    See Also:
    
    DoubleStream.sum(), DoubleStream.min(), DoubleStream.max(), DoubleStream.average()
  - reduce
```
public OptionalDouble reduce(DoubleBinaryOperator op)
```
    Description copied from interface: java.util.stream.DoubleStream
    Performs a reduction on the elements of this stream, using an associative accumulation function, and returns an OptionalDouble describing the reduced value, if any. This is equivalent to:
```
     boolean foundAny = false;
     double result = null;
     for (double element : this stream) {
         if (!foundAny) {
             foundAny = true;
             result = element;
         }
         else
             result = accumulator.applyAsDouble(result, element);
     }
     return foundAny ? OptionalDouble.of(result) : OptionalDouble.empty();
 
```
    but is not constrained to execute sequentially.
    The accumulator function must be an associative function.
    This is a terminal operation.
    Specified by:
    
    reduce in interface DoubleStream
    
    Parameters:
    
    op - an associative, non-interfering, stateless function for combining two values
    
    Returns:
    
    the result of the reduction
    
    See Also:
    
    DoubleStream.reduce(double, DoubleBinaryOperator)
  - collect
```
public <R> R collect(Supplier<R> supplier,
                     ObjDoubleConsumer<R> accumulator,
                     BiConsumer<R,R> combiner)
```
    Description copied from interface: java.util.stream.DoubleStream
    Performs a mutable reduction operation on the elements of this stream. A mutable reduction is one in which the reduced value is a mutable result container, such as an ArrayList, and elements are incorporated by updating the state of the result rather than by replacing the result. This produces a result equivalent to:
```
     R result = supplier.get();
     for (double element : this stream)
         accumulator.accept(result, element);
     return result;
 
```
    Like DoubleStream.reduce(double, DoubleBinaryOperator), collect operations can be parallelized without requiring additional synchronization.
    This is a terminal operation.
    Specified by:
    
    collect in interface DoubleStream
    
    Type Parameters:
    
    R - type of the result
    
    Parameters:
    
    supplier - a function that creates a new result container. For a parallel execution, this function may be called multiple times and must return a fresh value each time.
    
    accumulator - an associative, non-interfering, stateless function for incorporating an additional element into a result
    
    combiner - an associative, non-interfering, stateless function for combining two values, which must be compatible with the accumulator function
    
    Returns:
    
    the result of the reduction
    
    See Also:
    
    Stream.collect(Supplier, BiConsumer, BiConsumer)
  - sum
```
public double sum()
```
    Description copied from interface: java.util.stream.DoubleStream
    Returns the sum of elements in this stream. Summation is a special case of a reduction. If floating-point summation were exact, this method would be equivalent to:
```
     return reduce(0, Double::sum);
 
```
    However, since floating-point summation is not exact, the above code is not necessarily equivalent to the summation computation done by this method.
    If any stream element is a NaN or the sum is at any point a NaN then the sum will be NaN. The value of a floating-point sum is a function both of the input values as well as the order of addition operations. The order of addition operations of this method is intentionally not defined to allow for implementation flexibility to improve the speed and accuracy of the computed result. In particular, this method may be implemented using compensated summation or other technique to reduce the error bound in the numerical sum compared to a simple summation of double values.
    This is a terminal operation.
    Specified by:
    
    sum in interface DoubleStream
    
    Returns:
    
    the sum of elements in this stream
  - min
```
public OptionalDouble min()
```
    Description copied from interface: java.util.stream.DoubleStream
    Returns an OptionalDouble describing the minimum element of this stream, or an empty OptionalDouble if this stream is empty. The minimum element will be Double.NaN if any stream element was NaN. Unlike the numerical comparison operators, this method considers negative zero to be strictly smaller than positive zero. This is a special case of a reduction and is equivalent to:
```
     return reduce(Double::min);
 
```
    This is a terminal operation.
    Specified by:
    
    min in interface DoubleStream
    
    Returns:
    
    an OptionalDouble containing the minimum element of this stream, or an empty optional if the stream is empty
  - max
```
public OptionalDouble max()
```
    Description copied from interface: java.util.stream.DoubleStream
    Returns an OptionalDouble describing the maximum element of this stream, or an empty OptionalDouble if this stream is empty. The maximum element will be Double.NaN if any stream element was NaN. Unlike the numerical comparison operators, this method considers negative zero to be strictly smaller than positive zero. This is a special case of a reduction and is equivalent to:
```
     return reduce(Double::max);
 
```
    This is a terminal operation.
    Specified by:
    
    max in interface DoubleStream
    
    Returns:
    
    an OptionalDouble containing the maximum element of this stream, or an empty optional if the stream is empty
  - count
```
public long count()
```
    Description copied from interface: java.util.stream.DoubleStream
    Returns the count of elements in this stream. This is a special case of a reduction and is equivalent to:
```
     return mapToLong(e -> 1L).sum();
 
```
    This is a terminal operation.
    Specified by:
    
    count in interface DoubleStream
    
    Returns:
    
    the count of elements in this stream
  - average
```
public OptionalDouble average()
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns an OptionalDouble describing the arithmetic mean of elements of this stream, or an empty optional if this stream is empty. If any recorded value is a NaN or the sum is at any point a NaN then the average will be NaN.
    The average returned can vary depending upon the order in which values are recorded. This method may be implemented using compensated summation or other technique to reduce the error bound in the numerical sum used to compute the average.
    The average is a special case of a reduction.
    This is a terminal operation.
    
    Specified by:
    
    average in interface DoubleStream
    
    Returns:
    
    an OptionalDouble containing the average element of this stream, or an empty optional if the stream is empty
  - summaryStatistics
```
public DoubleSummaryStatistics summaryStatistics()
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns a DoubleSummaryStatistics describing various summary data about the elements of this stream. This is a special case of a reduction.
    This is a terminal operation.
    
    Specified by:
    
    summaryStatistics in interface DoubleStream
    
    Returns:
    
    a DoubleSummaryStatistics describing various summary data about the elements of this stream
  - anyMatch
```
public boolean anyMatch(DoublePredicate predicate)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns whether any elements of this stream match the provided predicate. May not evaluate the predicate on all elements if not necessary for determining the result. If the stream is empty then false is returned and the predicate is not evaluated.
    This is a short-circuiting terminal operation.
    
    Specified by:
    
    anyMatch in interface DoubleStream
    
    Parameters:
    
    predicate - a non-interfering, stateless predicate to apply to elements of this stream
    
    Returns:
    
    true if any elements of the stream match the provided predicate, otherwise false
  - allMatch
```
public boolean allMatch(DoublePredicate predicate)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns whether all elements of this stream match the provided predicate. May not evaluate the predicate on all elements if not necessary for determining the result. If the stream is empty then true is returned and the predicate is not evaluated.
    This is a short-circuiting terminal operation.
    
    Specified by:
    
    allMatch in interface DoubleStream
    
    Parameters:
    
    predicate - a non-interfering, stateless predicate to apply to elements of this stream
    
    Returns:
    
    true if either all elements of the stream match the provided predicate or the stream is empty, otherwise false
  - noneMatch
```
public boolean noneMatch(DoublePredicate predicate)
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns whether no elements of this stream match the provided predicate. May not evaluate the predicate on all elements if not necessary for determining the result. If the stream is empty then true is returned and the predicate is not evaluated.
    This is a short-circuiting terminal operation.
    
    Specified by:
    
    noneMatch in interface DoubleStream
    
    Parameters:
    
    predicate - a non-interfering, stateless predicate to apply to elements of this stream
    
    Returns:
    
    true if either no elements of the stream match the provided predicate or the stream is empty, otherwise false
  - findFirst
```
public OptionalDouble findFirst()
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns an OptionalDouble describing the first element of this stream, or an empty OptionalDouble if the stream is empty. If the stream has no encounter order, then any element may be returned.
    This is a short-circuiting terminal operation.
    
    Specified by:
    
    findFirst in interface DoubleStream
    
    Returns:
    
    an OptionalDouble describing the first element of this stream, or an empty OptionalDouble if the stream is empty
  - findAny
```
public OptionalDouble findAny()
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns an OptionalDouble describing some element of the stream, or an empty OptionalDouble if the stream is empty.
    This is a short-circuiting terminal operation.
    The behavior of this operation is explicitly nondeterministic; it is free to select any element in the stream. This is to allow for maximal performance in parallel operations; the cost is that multiple invocations on the same source may not return the same result. (If a stable result is desired, use DoubleStream.findFirst() instead.)
    
    Specified by:
    
    findAny in interface DoubleStream
    
    Returns:
    
    an OptionalDouble describing some element of this stream, or an empty OptionalDouble if the stream is empty
    
    See Also:
    
    DoubleStream.findFirst()
  - boxed
```
public Stream<Double> boxed()
```
    Description copied from interface: java.util.stream.DoubleStream
    
    Returns a Stream consisting of the elements of this stream, boxed to Double.
    This is an intermediate operation.
    
    Specified by:
    
    boxed in interface DoubleStream
    
    Returns:
    
    a Stream consistent of the elements of this stream, each boxed to a Double
  - iterator
```
public PrimitiveIterator.OfDouble iterator()
```
    Description copied from interface: java.util.stream.BaseStream
    
    Returns an iterator for the elements of this stream.
    This is a terminal operation.
    
    Specified by:
    
    iterator in interface BaseStream<Double,DoubleStream>
    
    Specified by:
    
    iterator in interface DoubleStream
    
    Returns:
    
    the element iterator for this stream
  - spliterator
```
public Spliterator.OfDouble spliterator()
```
    Description copied from interface: java.util.stream.BaseStream
    
    Returns a spliterator for the elements of this stream.
    This is a terminal operation.
    
    Specified by:
    
    spliterator in interface BaseStream<Double,DoubleStream>
    
    Specified by:
    
    spliterator in interface DoubleStream
    
    Returns:
    
    the element spliterator for this stream
  - isParallel
```
public boolean isParallel()
```
    Description copied from interface: java.util.stream.BaseStream
    
    Returns whether this stream, if a terminal operation were to be executed, would execute in parallel. Calling this method after invoking an terminal stream operation method may yield unpredictable results.
    
    Specified by:
    
    isParallel in interface BaseStream<T,S extends BaseStream<T,S>>
    
    Returns:
    
    true if this stream would execute in parallel if executed
  - sequential
```
public S sequential()
```
    Description copied from interface: java.util.stream.BaseStream
    
    Returns an equivalent stream that is sequential. May return itself, either because the stream was already sequential, or because the underlying stream state was modified to be sequential.
    This is an intermediate operation.
    
    Specified by:
    
    sequential in interface BaseStream<T,S extends BaseStream<T,S>>
    
    Returns:
    
    a sequential stream
  - parallel
```
public S parallel()
```
    Description copied from interface: java.util.stream.BaseStream
    
    Returns an equivalent stream that is parallel. May return itself, either because the stream was already parallel, or because the underlying stream state was modified to be parallel.
    This is an intermediate operation.
    
    Specified by:
    
    parallel in interface BaseStream<T,S extends BaseStream<T,S>>
    
    Returns:
    
    a parallel stream
  - unordered
```
public S unordered()
```
    Description copied from interface: java.util.stream.BaseStream
    
    Returns an equivalent stream that is unordered. May return itself, either because the stream was already unordered, or because the underlying stream state was modified to be unordered.
    This is an intermediate operation.
    
    Specified by:
    
    unordered in interface BaseStream<T,S extends BaseStream<T,S>>
    
    Returns:
    
    an unordered stream
  - onClose
```
public S onClose(Runnable closeHandler)
```
    Description copied from interface: java.util.stream.BaseStream
    
    Returns an equivalent stream with an additional close handler. Close handlers are run when the BaseStream.close() method is called on the stream, and are executed in the order they were added. All close handlers are run, even if earlier close handlers throw exceptions. If any close handler throws an exception, the first exception thrown will be relayed to the caller of close(), with any remaining exceptions added to that exception as suppressed exceptions (unless one of the remaining exceptions is the same exception as the first exception, since an exception cannot suppress itself.) May return itself.
    This is an intermediate operation.
    
    Specified by:
    
    onClose in interface BaseStream<T,S extends BaseStream<T,S>>
    
    Parameters:
    
    closeHandler - A task to execute when the stream is closed
    
    Returns:
    
    a stream with a handler that is run if the stream is closed
  - close
```
public void close()
```
    Description copied from interface: java.util.stream.BaseStream
    
    Closes this stream, causing all close handlers for this stream pipeline to be called.
    
    Specified by:
    
    close in interface AutoCloseable
    
    Specified by:
    
    close in interface BaseStream<T,S extends BaseStream<T,S>>
    
    See Also:
    
    AutoCloseable.close()
  - execute
```
protected void execute(Runnable terminalOperation)
```
  - execute
```
protected <R> R execute(Callable<R> terminalOperation)
```

Class ParallelDoubleStreamSupport

Nested Class Summary

Nested classes/interfaces inherited from interface java.util.stream.DoubleStream

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface java.util.stream.DoubleStream

Methods inherited from interface java.util.stream.BaseStream

Method Detail

parallelStream

parallelStream

parallelStream

parallelStream

iterate

generate

concat

filter

map

mapToObj

mapToInt

mapToLong

flatMap

distinct

sorted

peek

limit

skip

forEach

forEachOrdered

toArray

reduce

reduce

collect

sum

min

max

count

average

summaryStatistics

anyMatch

allMatch

noneMatch

findFirst

findAny

boxed

iterator

spliterator

isParallel

sequential

parallel

unordered

onClose

close

execute

execute