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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.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
* or visit www.oracle.com if you need additional information or have any
* questions.
*/
package com.landawn.abacus.util.stream;
import java.math.BigInteger;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Comparator;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.PrimitiveIterator;
import java.util.Queue;
import java.util.concurrent.TimeUnit;
import com.landawn.abacus.exception.AbacusException;
import com.landawn.abacus.util.ContinuableFuture;
import com.landawn.abacus.util.DateUtil;
import com.landawn.abacus.util.Fn;
import com.landawn.abacus.util.Holder;
import com.landawn.abacus.util.IndexedLong;
import com.landawn.abacus.util.LongIterator;
import com.landawn.abacus.util.LongList;
import com.landawn.abacus.util.LongMatrix;
import com.landawn.abacus.util.LongSummaryStatistics;
import com.landawn.abacus.util.MutableInt;
import com.landawn.abacus.util.N;
import com.landawn.abacus.util.Nth;
import com.landawn.abacus.util.Optional;
import com.landawn.abacus.util.OptionalDouble;
import com.landawn.abacus.util.OptionalLong;
import com.landawn.abacus.util.Pair;
import com.landawn.abacus.util.Percentage;
import com.landawn.abacus.util.Try;
import com.landawn.abacus.util.function.BiConsumer;
import com.landawn.abacus.util.function.BinaryOperator;
import com.landawn.abacus.util.function.BooleanSupplier;
import com.landawn.abacus.util.function.Function;
import com.landawn.abacus.util.function.LongBiFunction;
import com.landawn.abacus.util.function.LongBiPredicate;
import com.landawn.abacus.util.function.LongBinaryOperator;
import com.landawn.abacus.util.function.LongConsumer;
import com.landawn.abacus.util.function.LongFunction;
import com.landawn.abacus.util.function.LongNFunction;
import com.landawn.abacus.util.function.LongPredicate;
import com.landawn.abacus.util.function.LongSupplier;
import com.landawn.abacus.util.function.LongToDoubleFunction;
import com.landawn.abacus.util.function.LongToFloatFunction;
import com.landawn.abacus.util.function.LongToIntFunction;
import com.landawn.abacus.util.function.LongTriFunction;
import com.landawn.abacus.util.function.LongUnaryOperator;
import com.landawn.abacus.util.function.ObjLongConsumer;
import com.landawn.abacus.util.function.Supplier;
import com.landawn.abacus.util.function.ToLongFunction;
/**
* Note: It's copied from OpenJDK at: http://hg.openjdk.java.net/jdk8u/hs-dev/jdk
*
*
* A sequence of primitive long-valued elements supporting sequential and parallel
* aggregate operations. This is the {@code long} primitive specialization of
* {@link Stream}.
*
* The following example illustrates an aggregate operation using
* {@link Stream} and {@link LongStream}, computing the sum of the weights of the
* red widgets:
*
*
{@code
* long sum = widgets.stream()
* .filter(w -> w.getColor() == RED)
* .mapToLong(w -> w.getWeight())
* .sum();
* }
*
*
* @see Stream
*/
public abstract class LongStream extends StreamBase {
private static final LongStream EMPTY = new ArrayLongStream(N.EMPTY_LONG_ARRAY, true, null);
LongStream(final boolean sorted, final Collection closeHandlers) {
super(sorted, null, closeHandlers);
}
/**
* Returns a stream consisting of the results of applying the given
* function to the elements of this stream.
*
* This is an intermediate
* operation.
*
* @param mapper a non-interfering,
* stateless
* function to apply to each element
* @return the new stream
*/
public abstract LongStream map(LongUnaryOperator mapper);
/**
* Returns an {@code IntStream} consisting of the results of applying the
* given function to the elements of this stream.
*
*
This is an intermediate
* operation.
*
* @param mapper a non-interfering,
* stateless
* function to apply to each element
* @return the new stream
*/
public abstract IntStream mapToInt(LongToIntFunction mapper);
/**
* Returns a {@code FloatStream} consisting of the results of applying the
* given function to the elements of this stream.
*
*
This is an intermediate
* operation.
*
* @param mapper a non-interfering,
* stateless
* function to apply to each element
* @return the new stream
*/
public abstract FloatStream mapToFloat(LongToFloatFunction mapper);
/**
* Returns a {@code DoubleStream} consisting of the results of applying the
* given function to the elements of this stream.
*
*
This is an intermediate
* operation.
*
* @param mapper a non-interfering,
* stateless
* function to apply to each element
* @return the new stream
*/
public abstract DoubleStream mapToDouble(LongToDoubleFunction mapper);
/**
* Returns an object-valued {@code Stream} consisting of the results of
* applying the given function to the elements of this stream.
*
*
This is an
* intermediate operation.
*
* @param the element type of the new stream
* @param mapper a non-interfering,
* stateless
* function to apply to each element
* @return the new stream
*/
public abstract Stream mapToObj(LongFunction 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.
*
*
This is an intermediate
* operation.
*
* @param mapper a non-interfering,
* stateless
* function to apply to each element which produces a
* {@code LongStream} of new values
* @return the new stream
* @see Stream#flatMap(Function)
*/
public abstract LongStream flatMap(LongFunction mapper);
public abstract LongStream flattMap(LongFunction mapper);
public abstract IntStream flatMapToInt(LongFunction mapper);
public abstract FloatStream flatMapToFloat(LongFunction mapper);
public abstract DoubleStream flatMapToDouble(LongFunction mapper);
public abstract Stream flatMapToObj(LongFunction> mapper);
public abstract Stream flattMapToObj(LongFunction> mapper);
public abstract LongStream collapse(final LongBiPredicate collapsible, final LongBiFunction mergeFunction);
/**
* Returns a {@code Stream} produced by iterative application of a accumulation function
* to an initial element {@code seed} and next element of the current stream.
* Produces a {@code Stream} consisting of {@code seed}, {@code acc(seed, value1)},
* {@code acc(acc(seed, value1), value2)}, etc.
*
* This is an intermediate operation.
*
*
Example:
*
* accumulator: (a, b) -> a + b
* stream: [1, 2, 3, 4, 5]
* result: [1, 3, 6, 10, 15]
*
*
*
* This method only run sequentially, even in parallel stream.
*
* @param accumulator the accumulation function
* @return the new stream which has the extract same size as this stream.
*/
@SequentialOnly
public abstract LongStream scan(final LongBiFunction accumulator);
/**
* Returns a {@code Stream} produced by iterative application of a accumulation function
* to an initial element {@code seed} and next element of the current stream.
* Produces a {@code Stream} consisting of {@code seed}, {@code acc(seed, value1)},
* {@code acc(acc(seed, value1), value2)}, etc.
*
* This is an intermediate operation.
*
*
Example:
*
* seed:10
* accumulator: (a, b) -> a + b
* stream: [1, 2, 3, 4, 5]
* result: [11, 13, 16, 20, 25]
*
*
*
* This method only run sequentially, even in parallel stream.
*
* @param seed the initial value. it's only used once by accumulator to calculate the fist element in the returned stream.
* It will be ignored if this stream is empty and won't be the first element of the returned stream.
*
* @param accumulator the accumulation function
* @return the new stream which has the extract same size as this stream.
*/
@SequentialOnly
public abstract LongStream scan(final long seed, final LongBiFunction accumulator);
/**
*
* This method only run sequentially, even in parallel stream.
*
* @param n
* @return
*/
@SequentialOnly
public abstract LongStream top(int n);
/**
*
* This method only run sequentially, even in parallel stream.
*
* @param n
* @return
*/
@SequentialOnly
public abstract LongStream top(final int n, Comparator comparator);
public abstract LongList toLongList();
/**
*
* @param keyExtractor
* @param valueMapper
* @return
* @see Collectors#toMap(Function, Function)
*/
public abstract Map toMap(LongFunction keyExtractor, LongFunction valueMapper);
/**
*
* @param keyExtractor
* @param valueMapper
* @param mapFactory
* @return
* @see Collectors#toMap(Function, Function, Supplier)
*/
public abstract > M toMap(LongFunction keyExtractor, LongFunction valueMapper, Supplier mapFactory);
/**
*
* @param keyExtractor
* @param valueMapper
* @param mergeFunction
* @return
* @see Collectors#toMap(Function, Function, BinaryOperator)
*/
public abstract Map toMap(LongFunction keyExtractor, LongFunction valueMapper, BinaryOperator mergeFunction);
/**
*
* @param keyExtractor
* @param valueMapper
* @param mergeFunction
* @param mapFactory
* @return
* @see Collectors#toMap(Function, Function, BinaryOperator, Supplier)
*/
public abstract > M toMap(LongFunction keyExtractor, LongFunction valueMapper,
BinaryOperator mergeFunction, Supplier mapFactory);
/**
*
* @param classifier
* @param downstream
* @return
* @see Collectors#groupingBy(Function, Collector)
*/
public abstract Map toMap(final LongFunction classifier, final Collector downstream);
/**
*
* @param classifier
* @param downstream
* @param mapFactory
* @return
* @see Collectors#groupingBy(Function, Collector, Supplier)
*/
public abstract > M toMap(final LongFunction classifier, final Collector downstream,
final Supplier mapFactory);
public abstract LongMatrix toMatrix();
/**
* 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:
* {@code
* long result = identity;
* for (long element : this stream)
* result = accumulator.applyAsLong(result, element)
* return result;
* }
*
* but is not constrained to execute sequentially.
*
* The {@code identity} value must be an identity for the accumulator
* function. This means that for all {@code x},
* {@code accumulator.apply(identity, x)} is equal to {@code x}.
* The {@code accumulator} function must be an
* associative function.
*
*
This is a terminal
* operation.
*
* @apiNote Sum, min, max, and average are all special cases of reduction.
* Summing a stream of numbers can be expressed as:
*
*
{@code
* long sum = integers.reduce(0, (a, b) -> a+b);
* }
*
* or more compactly:
*
* {@code
* long sum = integers.reduce(0, Long::sum);
* }
*
* While this may seem a more roundabout way to perform an aggregation
* compared to simply mutating a running total in a loop, reduction
* operations parallelize more gracefully, without needing additional
* synchronization and with greatly reduced risk of data races.
*
* @param identity the identity value for the accumulating function
* @param op an associative,
* non-interfering,
* stateless
* function for combining two values
* @return the result of the reduction
* @see #sum()
* @see #min()
* @see #max()
* @see #average()
*/
public abstract long reduce(long identity, LongBinaryOperator op);
/**
* Performs a reduction on the
* elements of this stream, using an
* associative accumulation
* function, and returns an {@code OptionalLong} describing the reduced value,
* if any. This is equivalent to:
*
{@code
* boolean foundAny = false;
* long result = null;
* for (long element : this stream) {
* if (!foundAny) {
* foundAny = true;
* result = element;
* }
* else
* result = accumulator.applyAsLong(result, element);
* }
* return foundAny ? OptionalLong.of(result) : OptionalLong.empty();
* }
*
* but is not constrained to execute sequentially.
*
* The {@code accumulator} function must be an
* associative function.
*
*
This is a terminal
* operation.
*
* @param op an associative,
* non-interfering,
* stateless
* function for combining two values
* @return the result of the reduction
* @see #reduce(long, LongBinaryOperator)
*/
public abstract OptionalLong reduce(LongBinaryOperator op);
/**
* 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 {@code ArrayList}, and elements are incorporated by updating
* the state of the result rather than by replacing the result. This
* produces a result equivalent to:
*
{@code
* R result = supplier.get();
* for (long element : this stream)
* accumulator.accept(result, element);
* return result;
* }
*
* Like {@link #reduce(long, LongBinaryOperator)}, {@code collect} operations
* can be parallelized without requiring additional synchronization.
*
*
This is a terminal
* operation.
*
* @param type of the result
* @param 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.
* @param accumulator an associative,
* non-interfering,
* stateless
* function for incorporating an additional element into a result
* @param combiner an associative,
* non-interfering,
* stateless
* function for combining two values, which must be
* compatible with the accumulator function
* @return the result of the reduction
* @see Stream#collect(Supplier, BiConsumer, BiConsumer)
*/
public abstract R collect(Supplier supplier, ObjLongConsumer accumulator, BiConsumer combiner);
/**
*
* @param supplier
* @param accumulator
* @return
*/
public abstract R collect(Supplier supplier, ObjLongConsumer accumulator);
public abstract void forEach(final Try.LongConsumer action) throws E;
public abstract boolean anyMatch(final Try.LongPredicate predicate) throws E;
public abstract boolean allMatch(final Try.LongPredicate predicate) throws E;
public abstract boolean noneMatch(final Try.LongPredicate predicate) throws E;
public abstract OptionalLong findFirst(final Try.LongPredicate predicate) throws E;
public abstract OptionalLong findLast(final Try.LongPredicate predicate) throws E;
public abstract OptionalLong findFirstOrLast(Try.LongPredicate predicateForFirst,
Try.LongPredicate predicateForLast) throws E, E2;
public abstract OptionalLong findAny(final Try.LongPredicate predicate) throws E;
/**
* Head and tail should be used by pair. If only one is called, should use first() or skip(1) instead.
* Don't call any other methods with this stream after head() and tail() are called.
*
* @return
*/
public abstract OptionalLong head();
/**
* Head and tail should be used by pair. If only one is called, should use first() or skip(1) instead.
* Don't call any other methods with this stream after head() and tail() are called.
*
* @return
*/
public abstract LongStream tail();
public abstract Pair headAndTail();
// /**
// * Headd and taill should be used by pair.
// * Don't call any other methods with this stream after headd() and taill() are called.
// *
// * @return
// * @deprecated
// */
// @Deprecated
// public abstract LongStream headd();
//
// /**
// * Headd and taill should be used by pair.
// * Don't call any other methods with this stream after headd() and taill() are called.
// *
// * @return
// * @deprecated
// */
// @Deprecated
// public abstract OptionalLong taill();
//
// /**
// *
// * @return
// * @deprecated
// */
// @Deprecated
// public abstract Pair headAndTaill();
/**
* Returns an {@code OptionalLong} describing the minimum element of this
* stream, or an empty optional if this stream is empty. This is a special
* case of a reduction
* and is equivalent to:
* {@code
* return reduce(Long::min);
* }
*
* This is a terminal operation.
*
* @return an {@code OptionalLong} containing the minimum element of this
* stream, or an empty {@code OptionalLong} if the stream is empty
*/
public abstract OptionalLong min();
/**
* Returns an {@code OptionalLong} describing the maximum element of this
* stream, or an empty optional if this stream is empty. This is a special
* case of a reduction
* and is equivalent to:
*
{@code
* return reduce(Long::max);
* }
*
* This is a terminal
* operation.
*
* @return an {@code OptionalLong} containing the maximum element of this
* stream, or an empty {@code OptionalLong} if the stream is empty
*/
public abstract OptionalLong max();
/**
*
* @param k
* @return OptionalByte.empty() if there is no element or count less than k, otherwise the kth largest element.
*/
public abstract OptionalLong kthLargest(int k);
/**
* Returns the sum of elements in this stream. This is a special case
* of a reduction
* and is equivalent to:
*
{@code
* return reduce(0, Long::sum);
* }
*
* This is a terminal
* operation.
*
* @return the sum of elements in this stream
*/
public abstract long sum();
/**
* Returns an {@code OptionalDouble} describing the arithmetic mean of elements of
* this stream, or an empty optional if this stream is empty. This is a
* special case of a
* reduction.
*
*
This is a terminal
* operation.
*
* @return an {@code OptionalDouble} containing the average element of this
* stream, or an empty optional if the stream is empty
*/
public abstract OptionalDouble average();
public abstract LongSummaryStatistics summarize();
public abstract Pair>> summarizze();
/**
*
* @param b
* @param nextSelector first parameter is selected if Nth.FIRST is returned, otherwise the second parameter is selected.
* @return
*/
public abstract LongStream merge(final LongStream b, final LongBiFunction nextSelector);
public abstract LongStream zipWith(LongStream b, LongBiFunction zipFunction);
public abstract LongStream zipWith(LongStream b, LongStream c, LongTriFunction zipFunction);
public abstract LongStream zipWith(LongStream b, long valueForNoneA, long valueForNoneB, LongBiFunction zipFunction);
public abstract LongStream zipWith(LongStream b, LongStream c, long valueForNoneA, long valueForNoneB, long valueForNoneC,
LongTriFunction zipFunction);
/**
* Returns a {@code FloatStream} consisting of the elements of this stream,
* converted to {@code double}.
*
* This is an intermediate
* operation.
*
* @return a {@code FloatStream} consisting of the elements of this stream,
* converted to {@code double}
*/
public abstract FloatStream asFloatStream();
/**
* Returns a {@code DoubleStream} consisting of the elements of this stream,
* converted to {@code double}.
*
*
This is an intermediate
* operation.
*
* @return a {@code DoubleStream} consisting of the elements of this stream,
* converted to {@code double}
*/
public abstract DoubleStream asDoubleStream();
public abstract java.util.stream.LongStream toJdkStream();
/**
* Returns a {@code Stream} consisting of the elements of this stream,
* each boxed to a {@code Long}.
*
*
This is an intermediate
* operation.
*
* @return a {@code Stream} consistent of the elements of this stream,
* each boxed to {@code Long}
*/
public abstract Stream boxed();
@Override
public LongIterator iterator() {
return iteratorEx();
}
abstract LongIteratorEx iteratorEx();
@Override
public R __(Function transfer) {
return transfer.apply(this);
}
public static LongStream empty() {
return EMPTY;
}
@SafeVarargs
public static LongStream of(final long... a) {
return N.isNullOrEmpty(a) ? empty() : new ArrayLongStream(a);
}
public static LongStream of(final long[] a, final int startIndex, final int endIndex) {
return N.isNullOrEmpty(a) && (startIndex == 0 && endIndex == 0) ? empty() : new ArrayLongStream(a, startIndex, endIndex);
}
public static LongStream of(final long[][] a) {
return N.isNullOrEmpty(a) ? empty() : Stream.of(a).flatMapToLong(new Function() {
@Override
public LongStream apply(long[] t) {
return LongStream.of(t);
}
});
}
public static LongStream of(final long[][][] a) {
return N.isNullOrEmpty(a) ? empty() : Stream.of(a).flatMapToLong(new Function() {
@Override
public LongStream apply(long[][] t) {
return LongStream.of(t);
}
});
}
public static LongStream of(final Long[] a) {
return Stream.of(a).mapToLong(Fn.unboxL());
}
public static LongStream of(final Long[] a, final int startIndex, final int endIndex) {
return Stream.of(a, startIndex, endIndex).mapToLong(Fn.unboxL());
}
public static LongStream of(final Collection c) {
return Stream.of(c).mapToLong(Fn.unboxL());
}
public static LongStream of(final LongIterator iterator) {
return iterator == null ? empty() : new IteratorLongStream(iterator);
}
/**
* Lazy evaluation.
* @param supplier
* @return
*/
public static LongStream of(final Supplier supplier) {
final LongIterator iter = new LongIteratorEx() {
private LongIterator iterator = null;
@Override
public boolean hasNext() {
if (iterator == null) {
init();
}
return iterator.hasNext();
}
@Override
public long nextLong() {
if (iterator == null) {
init();
}
return iterator.nextLong();
}
private void init() {
final LongList c = supplier.get();
if (N.isNullOrEmpty(c)) {
iterator = LongIterator.empty();
} else {
iterator = c.iterator();
}
}
};
return of(iter);
}
public static LongStream of(final java.util.stream.LongStream stream) {
return of(new LongIteratorEx() {
private PrimitiveIterator.OfLong iter = null;
@Override
public boolean hasNext() {
if (iter == null) {
iter = stream.iterator();
}
return iter.hasNext();
}
@Override
public long nextLong() {
if (iter == null) {
iter = stream.iterator();
}
return iter.nextLong();
}
@Override
public long count() {
return iter == null ? stream.count() : super.count();
}
@Override
public void skip(long n) {
if (iter == null) {
iter = stream.skip(n).iterator();
} else {
super.skip(n);
}
}
@Override
public long[] toArray() {
return iter == null ? stream.toArray() : super.toArray();
}
}).onClose(new Runnable() {
@Override
public void run() {
stream.close();
}
});
}
public static LongStream range(final long startInclusive, final long endExclusive) {
if (startInclusive >= endExclusive) {
return empty();
} else if (endExclusive - startInclusive < 0) {
final long m = BigInteger.valueOf(endExclusive).subtract(BigInteger.valueOf(startInclusive)).divide(BigInteger.valueOf(3)).longValue();
return concat(range(startInclusive, startInclusive + m), range(startInclusive + m, (startInclusive + m) + m),
range((startInclusive + m) + m, endExclusive));
}
return new IteratorLongStream(new LongIteratorEx() {
private long next = startInclusive;
private long cnt = endExclusive - startInclusive;
@Override
public boolean hasNext() {
return cnt > 0;
}
@Override
public long nextLong() {
if (cnt-- <= 0) {
throw new NoSuchElementException();
}
return next++;
}
@Override
public void skip(long n) {
cnt = n >= cnt ? 0 : cnt - n;
next += n;
}
@Override
public long count() {
return cnt;
}
@Override
public long[] toArray() {
final long[] result = new long[(int) cnt];
for (int i = 0; i < cnt; i++) {
result[i] = next++;
}
cnt = 0;
return result;
}
});
}
public static LongStream range(final long startInclusive, final long endExclusive, final long by) {
if (by == 0) {
throw new IllegalArgumentException("'by' can't be zero");
}
if (endExclusive == startInclusive || endExclusive > startInclusive != by > 0) {
return empty();
}
if ((by > 0 && endExclusive - startInclusive < 0) || (by < 0 && startInclusive - endExclusive < 0)) {
long m = BigInteger.valueOf(endExclusive).subtract(BigInteger.valueOf(startInclusive)).divide(BigInteger.valueOf(3)).longValue();
if ((by > 0 && by > m) || (by < 0 && by < m)) {
return concat(range(startInclusive, startInclusive + by), range(startInclusive + by, endExclusive));
} else {
m = m > 0 ? m - m % by : m + m % by;
return concat(range(startInclusive, startInclusive + m, by), range(startInclusive + m, (startInclusive + m) + m, by),
range((startInclusive + m) + m, endExclusive, by));
}
}
return new IteratorLongStream(new LongIteratorEx() {
private long next = startInclusive;
private long cnt = (endExclusive - startInclusive) / by + ((endExclusive - startInclusive) % by == 0 ? 0 : 1);
@Override
public boolean hasNext() {
return cnt > 0;
}
@Override
public long nextLong() {
if (cnt-- <= 0) {
throw new NoSuchElementException();
}
long result = next;
next += by;
return result;
}
@Override
public void skip(long n) {
cnt = n >= cnt ? 0 : cnt - n;
next += n * by;
}
@Override
public long count() {
return cnt;
}
@Override
public long[] toArray() {
final long[] result = new long[(int) cnt];
for (int i = 0; i < cnt; i++, next += by) {
result[i] = next;
}
cnt = 0;
return result;
}
});
}
public static LongStream rangeClosed(final long startInclusive, final long endInclusive) {
if (startInclusive > endInclusive) {
return empty();
} else if (startInclusive == endInclusive) {
return of(startInclusive);
} else if (endInclusive - startInclusive + 1 <= 0) {
final long m = BigInteger.valueOf(endInclusive).subtract(BigInteger.valueOf(startInclusive)).divide(BigInteger.valueOf(3)).longValue();
return concat(range(startInclusive, startInclusive + m), range(startInclusive + m, (startInclusive + m) + m),
rangeClosed((startInclusive + m) + m, endInclusive));
}
return new IteratorLongStream(new LongIteratorEx() {
private long next = startInclusive;
private long cnt = endInclusive - startInclusive + 1;
@Override
public boolean hasNext() {
return cnt > 0;
}
@Override
public long nextLong() {
if (cnt-- <= 0) {
throw new NoSuchElementException();
}
return next++;
}
@Override
public void skip(long n) {
cnt = n >= cnt ? 0 : cnt - n;
next += n;
}
@Override
public long count() {
return cnt;
}
@Override
public long[] toArray() {
final long[] result = new long[(int) cnt];
for (int i = 0; i < cnt; i++) {
result[i] = next++;
}
cnt = 0;
return result;
}
});
}
public static LongStream rangeClosed(final long startInclusive, final long endInclusive, final long by) {
if (by == 0) {
throw new IllegalArgumentException("'by' can't be zero");
}
if (endInclusive == startInclusive) {
return of(startInclusive);
} else if (endInclusive > startInclusive != by > 0) {
return empty();
}
if ((by > 0 && endInclusive - startInclusive < 0) || (by < 0 && startInclusive - endInclusive < 0) || ((endInclusive - startInclusive) / by + 1 <= 0)) {
long m = BigInteger.valueOf(endInclusive).subtract(BigInteger.valueOf(startInclusive)).divide(BigInteger.valueOf(3)).longValue();
if ((by > 0 && by > m) || (by < 0 && by < m)) {
return concat(range(startInclusive, startInclusive + by), rangeClosed(startInclusive + by, endInclusive));
} else {
m = m > 0 ? m - m % by : m + m % by;
return concat(range(startInclusive, startInclusive + m, by), range(startInclusive + m, (startInclusive + m) + m, by),
rangeClosed((startInclusive + m) + m, endInclusive, by));
}
}
return new IteratorLongStream(new LongIteratorEx() {
private long next = startInclusive;
private long cnt = (endInclusive - startInclusive) / by + 1;
@Override
public boolean hasNext() {
return cnt > 0;
}
@Override
public long nextLong() {
if (cnt-- <= 0) {
throw new NoSuchElementException();
}
long result = next;
next += by;
return result;
}
@Override
public void skip(long n) {
cnt = n >= cnt ? 0 : cnt - n;
next += n * by;
}
@Override
public long count() {
return cnt;
}
@Override
public long[] toArray() {
final long[] result = new long[(int) cnt];
for (int i = 0; i < cnt; i++, next += by) {
result[i] = next;
}
cnt = 0;
return result;
}
});
}
public static LongStream repeat(final long element, final long n) {
N.checkArgNotNegative(n, "n");
if (n == 0) {
return empty();
}
return new IteratorLongStream(new LongIteratorEx() {
private long cnt = n;
@Override
public boolean hasNext() {
return cnt > 0;
}
@Override
public long nextLong() {
if (cnt-- <= 0) {
throw new NoSuchElementException();
}
return element;
}
@Override
public void skip(long n) {
cnt = n >= cnt ? 0 : cnt - (int) n;
}
@Override
public long count() {
return cnt;
}
@Override
public long[] toArray() {
final long[] result = new long[(int) cnt];
for (int i = 0; i < cnt; i++) {
result[i] = element;
}
cnt = 0;
return result;
}
});
}
public static LongStream random() {
return generate(new LongSupplier() {
@Override
public long getAsLong() {
return RAND.nextLong();
}
});
}
public static LongStream iterate(final BooleanSupplier hasNext, final LongSupplier next) {
N.checkArgNotNull(hasNext);
N.checkArgNotNull(next);
return new IteratorLongStream(new LongIteratorEx() {
private boolean hasNextVal = false;
@Override
public boolean hasNext() {
if (hasNextVal == false) {
hasNextVal = hasNext.getAsBoolean();
}
return hasNextVal;
}
@Override
public long nextLong() {
if (hasNextVal == false && hasNext() == false) {
throw new NoSuchElementException();
}
hasNextVal = false;
return next.getAsLong();
}
});
}
public static LongStream iterate(final long seed, final BooleanSupplier hasNext, final LongUnaryOperator f) {
N.checkArgNotNull(hasNext);
N.checkArgNotNull(f);
return new IteratorLongStream(new LongIteratorEx() {
private long t = 0;
private boolean isFirst = true;
private boolean hasNextVal = false;
@Override
public boolean hasNext() {
if (hasNextVal == false) {
hasNextVal = hasNext.getAsBoolean();
}
return hasNextVal;
}
@Override
public long nextLong() {
if (hasNextVal == false && hasNext() == false) {
throw new NoSuchElementException();
}
hasNextVal = false;
if (isFirst) {
isFirst = false;
t = seed;
} else {
t = f.applyAsLong(t);
}
return t;
}
});
}
/**
*
* @param seed
* @param hasNext test if has next by hasNext.test(seed) for first time and hasNext.test(f.apply(previous)) for remaining.
* @param f
* @return
*/
public static LongStream iterate(final long seed, final LongPredicate hasNext, final LongUnaryOperator f) {
N.checkArgNotNull(hasNext);
N.checkArgNotNull(f);
return new IteratorLongStream(new LongIteratorEx() {
private long t = 0;
private long cur = 0;
private boolean isFirst = true;
private boolean hasMore = true;
private boolean hasNextVal = false;
@Override
public boolean hasNext() {
if (hasNextVal == false && hasMore) {
if (isFirst) {
isFirst = false;
hasNextVal = hasNext.test(cur = seed);
} else {
hasNextVal = hasNext.test(cur = f.applyAsLong(t));
}
if (hasNextVal == false) {
hasMore = false;
}
}
return hasNextVal;
}
@Override
public long nextLong() {
if (hasNextVal == false && hasNext() == false) {
throw new NoSuchElementException();
}
t = cur;
hasNextVal = false;
return t;
}
});
}
public static LongStream iterate(final long seed, final LongUnaryOperator f) {
N.checkArgNotNull(f);
return new IteratorLongStream(new LongIteratorEx() {
private long t = 0;
private boolean isFirst = true;
@Override
public boolean hasNext() {
return true;
}
@Override
public long nextLong() {
if (isFirst) {
isFirst = false;
t = seed;
} else {
t = f.applyAsLong(t);
}
return t;
}
});
}
public static LongStream generate(final LongSupplier s) {
N.checkArgNotNull(s);
return new IteratorLongStream(new LongIteratorEx() {
@Override
public boolean hasNext() {
return true;
}
@Override
public long nextLong() {
return s.getAsLong();
}
});
}
/**
*
* @param intervalInMillis
* @return
*/
public static LongStream interval(final long intervalInMillis) {
return interval(0, intervalInMillis);
}
/**
* Generates the long value by the specified period: [0, 1, 2, 3...]
*
* @param delayInMillis
* @param intervalInMillis
* @return
*/
public static LongStream interval(final long delayInMillis, final long intervalInMillis) {
return interval(delayInMillis, intervalInMillis, TimeUnit.MILLISECONDS);
}
/**
* Generates the long value by the specified period: [0, 1, 2, 3...]
*
* @param delay
* @param interval
* @param unit
* @return
*/
public static LongStream interval(final long delay, final long interval, final TimeUnit unit) {
return of(new LongIteratorEx() {
private final long intervalInMillis = unit.toMillis(interval);
private long nextTime = DateUtil.currentMillis() + unit.toMillis(delay);
private long val = 0;
@Override
public boolean hasNext() {
return true;
}
@Override
public long nextLong() {
long now = DateUtil.currentMillis();
if (now < nextTime) {
N.sleep(nextTime - now);
}
nextTime += intervalInMillis;
return val++;
}
});
}
@SafeVarargs
public static LongStream concat(final long[]... a) {
return N.isNullOrEmpty(a) ? empty() : new IteratorLongStream(new LongIteratorEx() {
private final Iterator iter = N.asList(a).iterator();
private LongIterator cur;
@Override
public boolean hasNext() {
while ((cur == null || cur.hasNext() == false) && iter.hasNext()) {
cur = LongIteratorEx.of(iter.next());
}
return cur != null && cur.hasNext();
}
@Override
public long nextLong() {
if ((cur == null || cur.hasNext() == false) && hasNext() == false) {
throw new NoSuchElementException();
}
return cur.nextLong();
}
});
}
@SafeVarargs
public static LongStream concat(final LongIterator... a) {
return N.isNullOrEmpty(a) ? empty() : new IteratorLongStream(new LongIteratorEx() {
private final Iterator iter = N.asList(a).iterator();
private LongIterator cur;
@Override
public boolean hasNext() {
while ((cur == null || cur.hasNext() == false) && iter.hasNext()) {
cur = iter.next();
}
return cur != null && cur.hasNext();
}
@Override
public long nextLong() {
if ((cur == null || cur.hasNext() == false) && hasNext() == false) {
throw new NoSuchElementException();
}
return cur.nextLong();
}
});
}
@SafeVarargs
public static LongStream concat(final LongStream... a) {
return N.isNullOrEmpty(a) ? empty() : concat(N.asList(a));
}
public static LongStream concat(final Collection c) {
return N.isNullOrEmpty(c) ? empty() : new IteratorLongStream(new LongIteratorEx() {
private final Iterator iter = c.iterator();
private LongIterator cur;
@Override
public boolean hasNext() {
while ((cur == null || cur.hasNext() == false) && iter.hasNext()) {
cur = iter.next().iteratorEx();
}
return cur != null && cur.hasNext();
}
@Override
public long nextLong() {
if ((cur == null || cur.hasNext() == false) && hasNext() == false) {
throw new NoSuchElementException();
}
return cur.nextLong();
}
}).onClose(newCloseHandler(c));
}
/**
* Zip together the "a" and "b" arrays until one of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @return
*/
public static LongStream zip(final long[] a, final long[] b, final LongBiFunction zipFunction) {
return Stream.zip(a, b, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the "a", "b" and "c" arrays until one of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @return
*/
public static LongStream zip(final long[] a, final long[] b, final long[] c, final LongTriFunction zipFunction) {
return Stream.zip(a, b, c, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the "a" and "b" iterators until one of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @return
*/
public static LongStream zip(final LongIterator a, final LongIterator b, final LongBiFunction zipFunction) {
return Stream.zip(a, b, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the "a", "b" and "c" iterators until one of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @return
*/
public static LongStream zip(final LongIterator a, final LongIterator b, final LongIterator c, final LongTriFunction zipFunction) {
return Stream.zip(a, b, c, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the "a" and "b" streams until one of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @return
*/
public static LongStream zip(final LongStream a, final LongStream b, final LongBiFunction zipFunction) {
return Stream.zip(a, b, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the "a", "b" and "c" streams until one of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @return
*/
public static LongStream zip(final LongStream a, final LongStream b, final LongStream c, final LongTriFunction zipFunction) {
return Stream.zip(a, b, c, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the iterators until one of them runs out of values.
* Each array of values is combined into a single value using the supplied zipFunction function.
*
* @param c
* @param zipFunction
* @return
*/
public static LongStream zip(final Collection c, final LongNFunction zipFunction) {
return Stream.zip(c, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the "a" and "b" iterators until all of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @param valueForNoneA value to fill if "a" runs out of values first.
* @param valueForNoneB value to fill if "b" runs out of values first.
* @param zipFunction
* @return
*/
public static LongStream zip(final long[] a, final long[] b, final long valueForNoneA, final long valueForNoneB, final LongBiFunction zipFunction) {
return Stream.zip(a, b, valueForNoneA, valueForNoneB, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the "a", "b" and "c" iterators until all of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @param c
* @param valueForNoneA value to fill if "a" runs out of values.
* @param valueForNoneB value to fill if "b" runs out of values.
* @param valueForNoneC value to fill if "c" runs out of values.
* @param zipFunction
* @return
*/
public static LongStream zip(final long[] a, final long[] b, final long[] c, final long valueForNoneA, final long valueForNoneB, final long valueForNoneC,
final LongTriFunction zipFunction) {
return Stream.zip(a, b, c, valueForNoneA, valueForNoneB, valueForNoneC, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the "a" and "b" iterators until all of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @param valueForNoneA value to fill if "a" runs out of values first.
* @param valueForNoneB value to fill if "b" runs out of values first.
* @param zipFunction
* @return
*/
public static LongStream zip(final LongIterator a, final LongIterator b, final long valueForNoneA, final long valueForNoneB,
final LongBiFunction zipFunction) {
return Stream.zip(a, b, valueForNoneA, valueForNoneB, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the "a", "b" and "c" iterators until all of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @param c
* @param valueForNoneA value to fill if "a" runs out of values.
* @param valueForNoneB value to fill if "b" runs out of values.
* @param valueForNoneC value to fill if "c" runs out of values.
* @param zipFunction
* @return
*/
public static LongStream zip(final LongIterator a, final LongIterator b, final LongIterator c, final long valueForNoneA, final long valueForNoneB,
final long valueForNoneC, final LongTriFunction zipFunction) {
return Stream.zip(a, b, c, valueForNoneA, valueForNoneB, valueForNoneC, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the "a" and "b" iterators until all of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @param valueForNoneA value to fill if "a" runs out of values first.
* @param valueForNoneB value to fill if "b" runs out of values first.
* @param zipFunction
* @return
*/
public static LongStream zip(final LongStream a, final LongStream b, final long valueForNoneA, final long valueForNoneB,
final LongBiFunction zipFunction) {
return Stream.zip(a, b, valueForNoneA, valueForNoneB, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the "a", "b" and "c" iterators until all of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction function.
*
* @param a
* @param b
* @param c
* @param valueForNoneA value to fill if "a" runs out of values.
* @param valueForNoneB value to fill if "b" runs out of values.
* @param valueForNoneC value to fill if "c" runs out of values.
* @param zipFunction
* @return
*/
public static LongStream zip(final LongStream a, final LongStream b, final LongStream c, final long valueForNoneA, final long valueForNoneB,
final long valueForNoneC, final LongTriFunction zipFunction) {
return Stream.zip(a, b, c, valueForNoneA, valueForNoneB, valueForNoneC, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
* Zip together the iterators until all of them runs out of values.
* Each array of values is combined into a single value using the supplied zipFunction function.
*
* @param c
* @param valuesForNone value to fill for any iterator runs out of values.
* @param zipFunction
* @return
*/
public static LongStream zip(final Collection c, final long[] valuesForNone, final LongNFunction zipFunction) {
return Stream.zip(c, valuesForNone, zipFunction).mapToLong(ToLongFunction.UNBOX);
}
/**
*
* @param a
* @param b
* @param nextSelector first parameter is selected if Nth.FIRST is returned, otherwise the second parameter is selected.
* @return
*/
public static LongStream merge(final long[] a, final long[] b, final LongBiFunction nextSelector) {
if (N.isNullOrEmpty(a)) {
return of(b);
} else if (N.isNullOrEmpty(b)) {
return of(a);
}
return new IteratorLongStream(new LongIteratorEx() {
private final int lenA = a.length;
private final int lenB = b.length;
private int cursorA = 0;
private int cursorB = 0;
@Override
public boolean hasNext() {
return cursorA < lenA || cursorB < lenB;
}
@Override
public long nextLong() {
if (cursorA < lenA) {
if (cursorB < lenB) {
if (nextSelector.apply(a[cursorA], b[cursorB]) == Nth.FIRST) {
return a[cursorA++];
} else {
return b[cursorB++];
}
} else {
return a[cursorA++];
}
} else if (cursorB < lenB) {
return b[cursorB++];
} else {
throw new NoSuchElementException();
}
}
});
}
/**
*
* @param a
* @param b
* @param c
* @param nextSelector first parameter is selected if Nth.FIRST is returned, otherwise the second parameter is selected.
* @return
*/
public static LongStream merge(final long[] a, final long[] b, final long[] c, final LongBiFunction nextSelector) {
return merge(merge(a, b, nextSelector).iteratorEx(), LongStream.of(c).iteratorEx(), nextSelector);
}
/**
*
* @param a
* @param b
* @param nextSelector first parameter is selected if Nth.FIRST is returned, otherwise the second parameter is selected.
* @return
*/
public static LongStream merge(final LongIterator a, final LongIterator b, final LongBiFunction nextSelector) {
if (a.hasNext() == false) {
return of(b);
} else if (b.hasNext() == false) {
return of(a);
}
return new IteratorLongStream(new LongIteratorEx() {
private long nextA = 0;
private long nextB = 0;
private boolean hasNextA = false;
private boolean hasNextB = false;
@Override
public boolean hasNext() {
return a.hasNext() || b.hasNext() || hasNextA || hasNextB;
}
@Override
public long nextLong() {
if (hasNextA) {
if (b.hasNext()) {
if (nextSelector.apply(nextA, (nextB = b.nextLong())) == Nth.FIRST) {
hasNextA = false;
hasNextB = true;
return nextA;
} else {
return nextB;
}
} else {
hasNextA = false;
return nextA;
}
} else if (hasNextB) {
if (a.hasNext()) {
if (nextSelector.apply((nextA = a.nextLong()), nextB) == Nth.FIRST) {
return nextA;
} else {
hasNextA = true;
hasNextB = false;
return nextB;
}
} else {
hasNextB = false;
return nextB;
}
} else if (a.hasNext()) {
if (b.hasNext()) {
if (nextSelector.apply((nextA = a.nextLong()), (nextB = b.nextLong())) == Nth.FIRST) {
hasNextB = true;
return nextA;
} else {
hasNextA = true;
return nextB;
}
} else {
return a.nextLong();
}
} else if (b.hasNext()) {
return b.nextLong();
} else {
throw new NoSuchElementException();
}
}
});
}
/**
*
* @param a
* @param b
* @param c
* @param nextSelector first parameter is selected if Nth.FIRST is returned, otherwise the second parameter is selected.
* @return
*/
public static LongStream merge(final LongIterator a, final LongIterator b, final LongIterator c, final LongBiFunction nextSelector) {
return merge(merge(a, b, nextSelector).iteratorEx(), c, nextSelector);
}
/**
*
* @param a
* @param b
* @param nextSelector first parameter is selected if Nth.FIRST is returned, otherwise the second parameter is selected.
* @return
*/
public static LongStream merge(final LongStream a, final LongStream b, final LongBiFunction nextSelector) {
return merge(a.iteratorEx(), b.iteratorEx(), nextSelector).onClose(newCloseHandler(N.asList(a, b)));
}
/**
*
* @param a
* @param b
* @param c
* @param nextSelector first parameter is selected if Nth.FIRST is returned, otherwise the second parameter is selected.
* @return
*/
public static LongStream merge(final LongStream a, final LongStream b, final LongStream c, final LongBiFunction nextSelector) {
return merge(N.asList(a, b, c), nextSelector);
}
/**
*
* @param c
* @param nextSelector first parameter is selected if Nth.FIRST is returned, otherwise the second parameter is selected.
* @return
*/
public static LongStream merge(final Collection c, final LongBiFunction nextSelector) {
if (N.isNullOrEmpty(c)) {
return empty();
} else if (c.size() == 1) {
return c.iterator().next();
} else if (c.size() == 2) {
final Iterator iter = c.iterator();
return merge(iter.next(), iter.next(), nextSelector);
}
final Iterator iter = c.iterator();
LongStream result = merge(iter.next().iteratorEx(), iter.next().iteratorEx(), nextSelector);
while (iter.hasNext()) {
result = merge(result.iteratorEx(), iter.next().iteratorEx(), nextSelector);
}
return result.onClose(newCloseHandler(c));
}
/**
*
* @param c
* @param nextSelector first parameter is selected if Nth.FIRST is returned, otherwise the second parameter is selected.
* @return
*/
public static LongStream parallelMerge(final Collection c, final LongBiFunction nextSelector) {
return parallelMerge(c, nextSelector, DEFAULT_MAX_THREAD_NUM);
}
/**
*
* @param c
* @param nextSelector first parameter is selected if Nth.FIRST is returned, otherwise the second parameter is selected.
* @param maxThreadNum
* @return
*/
public static LongStream parallelMerge(final Collection c, final LongBiFunction nextSelector, final int maxThreadNum) {
checkMaxThreadNum(maxThreadNum);
if (N.isNullOrEmpty(c)) {
return empty();
} else if (c.size() == 1) {
return c.iterator().next();
} else if (c.size() == 2) {
final Iterator iter = c.iterator();
return merge(iter.next(), iter.next(), nextSelector);
} else if (maxThreadNum <= 1) {
return merge(c, nextSelector);
}
final Queue queue = N.newLinkedList();
for (LongStream e : c) {
queue.add(e.iteratorEx());
}
final Holder eHolder = new Holder<>();
final MutableInt cnt = MutableInt.of(c.size());
final List> futureList = new ArrayList<>(c.size() - 1);
for (int i = 0, n = N.min(maxThreadNum, c.size() / 2 + 1); i < n; i++) {
futureList.add(asyncExecutor.execute(new Runnable() {
@Override
public void run() {
LongIterator a = null;
LongIterator b = null;
LongIterator c = null;
try {
while (eHolder.value() == null) {
synchronized (queue) {
if (cnt.intValue() > 2 && queue.size() > 1) {
a = queue.poll();
b = queue.poll();
cnt.decrement();
} else {
break;
}
}
c = LongIteratorEx.of(merge(a, b, nextSelector).toArray());
synchronized (queue) {
queue.offer(c);
}
}
} catch (Exception e) {
setError(eHolder, e);
}
}
}));
}
complete(futureList, eHolder);
// Should never happen.
if (queue.size() != 2) {
throw new AbacusException("Unknown error happened.");
}
return merge(queue.poll(), queue.poll(), nextSelector).onClose(newCloseHandler(c));
}
public static abstract class LongStreamEx extends LongStream {
private LongStreamEx(boolean sorted, Collection closeHandlers) {
super(sorted, closeHandlers);
// Factory class.
}
}
}