Package org.apache.sis.internal.stream

Class PaginedDoubleStream

java.lang.Object

org.apache.sis.internal.stream.BaseStreamWrapper<Double,DoubleStream>

org.apache.sis.internal.stream.DoubleStreamWrapper

org.apache.sis.internal.stream.PaginedDoubleStream

All Implemented Interfaces:

AutoCloseable, BaseStream<Double,DoubleStream>, DoubleStream

public final class PaginedDoubleStream
extends DoubleStreamWrapper

A stream on which skip and limit operations are delegated to a root stream. This is useful when the root stream is capable of some optimizations, for example using SQL. The redirection stops as soon as an operation may change the elements order or filtering.

Since:

1.1

Version:

1.1

Nested Class Summary

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

DoubleStream.Builder

Field Summary

Fields

Modifier and Type	Field	Description
private Stream<?>	root	The root stream on which to delegate skip and limit operations.

Fields inherited from class org.apache.sis.internal.stream.BaseStreamWrapper

toClose

Constructor Summary

Constructors

Constructor	Description
PaginedDoubleStream(DoubleStream source, Stream<?> root)	Creates a new mapped stream.

Method Summary

Modifier and Type	Method	Description
long	count()	Returns the number of elements in this stream.
DoubleStream	distinct()	Returns a stream with distinct elements of this stream.
DoubleStream	filter(DoublePredicate predicate)	Returns a stream with elements of this stream that match the given predicate.
DoubleStream	limit(long maxSize)	Truncates this stream to the given number of elements.
DoubleStream	map(DoubleUnaryOperator mapper)	Returns a stream with results of applying the given function to the elements of this stream.
DoubleStream	skip(long n)	Discards the specified number of elements.
DoubleStream	sorted()	Returns a stream with elements of this stream sorted in ascending order.
DoubleStream	unordered()	Returns an equivalent stream that is unordered.

Methods inherited from class org.apache.sis.internal.stream.DoubleStreamWrapper

allMatch, anyMatch, average, boxed, collect, delegate, findAny, findFirst, flatMap, forEach, forEachOrdered, iterator, mapToInt, mapToLong, mapToObj, max, min, noneMatch, onClose, parallel, peek, reduce, reduce, sequential, source, spliterator, sum, summaryStatistics, toArray

Methods inherited from class org.apache.sis.internal.stream.BaseStreamWrapper

close, inactive, isParallel

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.BaseStream

close, isParallel

Field Details

root

private Stream<?> root

The root stream on which to delegate skip and limit operations.

Constructor Details

PaginedDoubleStream

public PaginedDoubleStream(DoubleStream source,
 Stream<?> root)

Creates a new mapped stream.

Parameters:

source - the stream to wrap.

root - the stream on which to delegate skip and limit operations.

Method Details

skip

public DoubleStream skip(long n)

Discards the specified number of elements. This method delegates the operation to the root stream.

Specified by:

skip in interface DoubleStream

Overrides:

skip in class DoubleStreamWrapper

Parameters:

n - number of elements to skip.

Returns:

this.

limit

public DoubleStream limit(long maxSize)

Truncates this stream to the given number of elements. This method delegates the operation to the root stream.

Specified by:

limit in interface DoubleStream

Overrides:

limit in class DoubleStreamWrapper

Parameters:

maxSize - number of elements to keep.

Returns:

this.

count

public long count()

Returns the number of elements in this stream. This method delegates the operation to the root stream.

Specified by:

count in interface DoubleStream

Overrides:

count in class DoubleStreamWrapper

Returns:

number of elements in this stream.

map

public DoubleStream map(DoubleUnaryOperator mapper)

Description copied from class: DoubleStreamWrapper

Returns a stream with results of applying the given function to the elements of this stream.

Specified by:

map in interface DoubleStream

Overrides:

map in class DoubleStreamWrapper

distinct

public DoubleStream distinct()

Description copied from class: DoubleStreamWrapper

Returns a stream with distinct elements of this stream.

Specified by:

distinct in interface DoubleStream

Overrides:

distinct in class DoubleStreamWrapper

unordered

public DoubleStream unordered()

Description copied from class: DoubleStreamWrapper

Returns an equivalent stream that is unordered.

Specified by:

unordered in interface BaseStream<Double,DoubleStream>

Overrides:

unordered in class DoubleStreamWrapper

sorted

public DoubleStream sorted()

Description copied from class: DoubleStreamWrapper

Returns a stream with elements of this stream sorted in ascending order.

Specified by:

sorted in interface DoubleStream

Overrides:

sorted in class DoubleStreamWrapper

filter

public DoubleStream filter(DoublePredicate predicate)

Description copied from class: DoubleStreamWrapper

Returns a stream with elements of this stream that match the given predicate.

Specified by:

filter in interface DoubleStream

Overrides:

filter in class DoubleStreamWrapper