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/*
* Copyright (C) 2016, 2017, 2018, 2019 HaiYang Li
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
* in compliance with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software distributed under the License
* is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
* or implied. See the License for the specific language governing permissions and limitations under
* the License.
*/
package com.landawn.abacus.util.stream;
import java.io.File;
import java.io.IOException;
import java.io.Reader;
import java.nio.CharBuffer;
import java.security.SecureRandom;
import java.util.Arrays;
import java.util.Collection;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.NoSuchElementException;
import java.util.Random;
import java.util.function.BiConsumer;
import java.util.function.BiFunction;
import java.util.function.BiPredicate;
import java.util.function.BinaryOperator;
import java.util.function.BooleanSupplier;
import java.util.function.Function;
import java.util.function.Predicate;
import java.util.function.Supplier;
import java.util.function.UnaryOperator;
import java.util.stream.Collector;
import com.landawn.abacus.annotation.*;
import com.landawn.abacus.exception.UncheckedIOException;
import com.landawn.abacus.util.Array;
import com.landawn.abacus.util.CharIterator;
import com.landawn.abacus.util.CharList;
import com.landawn.abacus.util.CharSummaryStatistics;
import com.landawn.abacus.util.Fn;
import com.landawn.abacus.util.Fn.BiConsumers;
import com.landawn.abacus.util.Fn.FC;
import com.landawn.abacus.util.IOUtil;
import com.landawn.abacus.util.IndexedChar;
import com.landawn.abacus.util.MergeResult;
import com.landawn.abacus.util.N;
import com.landawn.abacus.util.Pair;
import com.landawn.abacus.util.Percentage;
import com.landawn.abacus.util.Strings;
import com.landawn.abacus.util.Throwables;
import com.landawn.abacus.util.cs;
import com.landawn.abacus.util.function.*;
import com.landawn.abacus.util.u.Optional;
import com.landawn.abacus.util.u.OptionalChar;
import com.landawn.abacus.util.u.OptionalDouble;
/**
* The CharStream class is an abstract class that represents a stream of char elements and supports different kinds of computations.
* The Stream operations are divided into intermediate and terminal operations, and are combined to form stream pipelines.
*
*
* The Stream will be automatically closed after a terminal method is called/triggered.
*
*
*
* Refer to {@code com.landawn.abacus.util.stream.BaseStream} and {@code com.landawn.abacus.util.stream.Stream} for more APIs docs.
*
* @see Stream
* @see BaseStream
*/
@Immutable
@LazyEvaluation
public abstract class CharStream extends StreamBase {
static final Random RAND = new SecureRandom();
CharStream(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
*/
@ParallelSupported
@IntermediateOp
public abstract CharStream map(CharUnaryOperator mapper);
/**
* Returns a {@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
*/
@ParallelSupported
@IntermediateOp
public abstract IntStream mapToInt(CharToIntFunction 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
*/
@ParallelSupported
@IntermediateOp
public abstract Stream mapToObj(CharFunction 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 an
* {@code CharStream} of new values
* @return
* @see Stream#flatMap(Function)
*/
@ParallelSupported
@IntermediateOp
public abstract CharStream flatMap(CharFunction mapper);
// public abstract CharStream flatmap(CharFunction mapper);
/**
*
* @param mapper
* @return
*/
@ParallelSupported
@IntermediateOp
public abstract CharStream flatmap(CharFunction mapper); //NOSONAR
/**
*
* @param mapper
* @return
*/
@ParallelSupported
@IntermediateOp
public abstract IntStream flatMapToInt(CharFunction mapper);
/**
*
* @param
* @param mapper
* @return
*/
@ParallelSupported
@IntermediateOp
public abstract Stream flatMapToObj(CharFunction> mapper);
/**
*
* @param
* @param mapper
* @return
*/
@ParallelSupported
@IntermediateOp
public abstract Stream flatmapToObj(CharFunction> mapper); //NOSONAR
/**
*
* @param
* @param mapper
* @return
*/
@Beta
@ParallelSupported
@IntermediateOp
public abstract Stream flattMapToObj(CharFunction mapper);
/**
* Note: copied from StreamEx: StreamEx
*
* @param mapper
* @return
*/
@Beta
@ParallelSupported
@IntermediateOp
public abstract CharStream mapPartial(CharFunction mapper);
/**
* Note: copied from StreamEx: StreamEx
*
*
* Returns a stream consisting of results of applying the given function to
* the ranges created from the source elements.
* This is a quasi-intermediate
* partial reduction operation.
*
* @param sameRange a non-interfering, stateless predicate to apply to
* the leftmost and next elements which returns {@code true} for elements
* which belong to the same range.
* @param mapper a non-interfering, stateless function to apply to the
* range borders and produce the resulting element. If value was
* not merged to the interval, then mapper will receive the same
* value twice, otherwise it will receive the leftmost and the
* rightmost values which were merged to the range.
* @return
* @see #collapse(CharBiPredicate, CharBinaryOperator)
* @see Stream#rangeMap(BiPredicate, BiFunction)
*/
@SequentialOnly
@IntermediateOp
public abstract CharStream rangeMap(final CharBiPredicate sameRange, final CharBinaryOperator mapper);
/**
* Note: copied from StreamEx: StreamEx
*
*
* Returns a stream consisting of results of applying the given function to
* the ranges created from the source elements.
* This is a quasi-intermediate
* partial reduction operation.
*
* @param
* @param sameRange a non-interfering, stateless predicate to apply to
* the leftmost and next elements which returns {@code true} for elements
* which belong to the same range.
* @param mapper a non-interfering, stateless function to apply to the
* range borders and produce the resulting element. If value was
* not merged to the interval, then mapper will receive the same
* value twice, otherwise it will receive the leftmost and the
* rightmost values which were merged to the range.
* @return
* @see Stream#rangeMap(BiPredicate, BiFunction)
*/
@SequentialOnly
@IntermediateOp
public abstract Stream rangeMapToObj(final CharBiPredicate sameRange, final CharBiFunction mapper);
/**
* Merges a series of adjacent elements in the stream which satisfy the given predicate into a List.
* The predicate takes two parameters: the previous element and the current element in the stream.
* If the predicate returns {@code true}, the current element and its previous element are considered as a series of adjacent elements.
* These elements are then collapsed into a List.
*
* This is an intermediate operation, meaning it's always lazy. It doesn't start processing the data until a terminal operation is invoked on the stream pipeline.
* It's also a stateful operation since it needs to remember the previous element when processing the current element.
*
* This operation is not parallelizable and requires the stream to be ordered.
*
* @param collapsible a BiPredicate that takes two parameters: the previous element and the current element in the stream.
* @return a new Stream where each element is a List of adjacent elements which satisfy the given predicate.
* @see Stream#collapse(BiPredicate)
*/
@SequentialOnly
@IntermediateOp
public abstract Stream collapse(final CharBiPredicate collapsible);
/**
* Merges a series of adjacent elements in the stream which satisfy the given predicate using the merger function and returns a new stream.
* The predicate takes two parameters: the previous element and the current element in the stream.
* If the predicate returns {@code true}, the current element and its previous element are considered as a series of adjacent elements.
* These elements are then merged using the provided BiFunction.
*
* This is an intermediate operation, meaning it's always lazy. It doesn't start processing the data until a terminal operation is invoked on the stream pipeline.
* It's also a stateful operation since it needs to remember the previous element when processing the current element.
*
* This operation is not parallelizable and requires the stream to be ordered.
*
* @param collapsible a BiPredicate that takes two parameters: the previous element and the current element in the stream.
* @param mergeFunction a BiFunction that takes two parameters: the result of the previous merge operation (or the first element if no merge has been performed yet) and the current element, and returns the result of the merge operation.
* @return a new Stream where each element is the result of merging adjacent elements which satisfy the given predicate.
* @see Stream#collapse(BiPredicate, BiFunction)
*/
@SequentialOnly
@IntermediateOp
public abstract CharStream collapse(final CharBiPredicate collapsible, final CharBinaryOperator mergeFunction);
/**
* Merges a series of adjacent elements in the stream which satisfy the given predicate into a single element and returns a new stream.
* The predicate takes three parameters: the first element of the series, the previous element and the current element in the stream.
* If the predicate returns {@code true}, the current element, its previous element and the first element of the series are considered as a series of adjacent elements.
* These elements are then collapsed into a single element using the provided merge function.
*
* This is an intermediate operation, meaning it's always lazy. It doesn't start processing the data until a terminal operation is invoked on the stream pipeline.
* It's also a stateful operation since it needs to remember the first and previous elements when processing the current element.
*
* This operation is not parallelizable and requires the stream to be ordered.
*
* @param collapsible a TriPredicate that takes three parameters: the first element of the series, the previous element and the current element in the stream.
* @param mergeFunction a BiFunction that takes two parameters: the current element and its previous element. It returns a single element that represents the collapsed elements.
* @return a new Stream where each element is the result of collapsing adjacent elements which satisfy the given predicate.
* @see Stream#collapse(TriPredicate, BiFunction)
*/
@SequentialOnly
@IntermediateOp
public abstract CharStream collapse(final CharTriPredicate collapsible, final CharBinaryOperator mergeFunction);
/**
* Performs a scan (also known as prefix sum, cumulative sum, running total, or integral) operation on the elements of the stream.
* The scan operation takes a binary operator (the accumulator) and applies it cumulatively on the stream elements,
* successively combining each element in order from the start to produce a stream of accumulated results.
*
* For example, given a stream of numbers [1, 2, 3, 4], and an accumulator that performs addition,
* the output would be a stream of numbers [1, 3, 6, 10].
*
* This is an intermediate operation.
* This operation is sequential only, even when called on a parallel stream.
*
* @param accumulator a {@code CharBinaryOperator} that takes two parameters: the current accumulated value and the current stream element, and returns a new accumulated value.
* @return a new {@code CharStream} consisting of the results of the scan operation on the elements of the original stream.
* @see Stream#scan(BiFunction)
*/
@SequentialOnly
@IntermediateOp
public abstract CharStream scan(final CharBinaryOperator accumulator);
/**
* Performs a scan (also known as prefix sum, cumulative sum, running total, or integral) operation on the elements of the stream.
* The scan operation takes an initial value and a binary operator (the accumulator) and applies it cumulatively on the stream elements,
* successively combining each element in order from the start to produce a stream of accumulated results.
*
* For example, given a stream of numbers [1, 2, 3, 4], an initial value of 10, and an accumulator that performs addition,
* the output would be a stream of numbers [11, 13, 16, 20].
* This is an intermediate operation.
* This operation is sequential only, even when called on a parallel stream.
*
* @param init the initial value. It's only used once by the accumulator to calculate the first 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 a {@code CharBinaryOperator} that takes two parameters: the current accumulated value and the current stream element, and returns a new accumulated value.
* @return a new {@code CharStream} consisting of the results of the scan operation on the elements of the original stream.
* @see Stream#scan(Object, BiFunction)
*/
@SequentialOnly
@IntermediateOp
public abstract CharStream scan(final char init, final CharBinaryOperator accumulator);
/**
* Performs a scan (also known as prefix sum, cumulative sum, running total, or integral) operation on the elements of the stream.
* The scan operation takes an initial value and a binary operator (the accumulator) and applies it cumulatively on the stream elements,
* successively combining each element in order from the start to produce a stream of accumulated results.
*
* This is an intermediate operation.
* This operation is sequential only, even when called on a parallel stream.
*
* @param init the initial value. It's only used once by the accumulator to calculate the first element in the returned stream.
* @param initIncluded a boolean value that determines if the initial value should be included as the first element in the returned stream.
* @param accumulator a {@code CharBinaryOperator} that takes two parameters: the current accumulated value and the current stream element, and returns a new accumulated value.
* @return a new {@code CharStream} consisting of the results of the scan operation on the elements of the original stream.
* @see Stream#scan(Object, boolean, BiFunction)
*/
@SequentialOnly
@IntermediateOp
public abstract CharStream scan(final char init, final boolean initIncluded, final CharBinaryOperator accumulator);
/**
*
* @param a
* @return
*/
@SequentialOnly
@IntermediateOp
public abstract CharStream prepend(final char... a);
/**
*
* @param a
* @return
*/
@SequentialOnly
@IntermediateOp
public abstract CharStream append(final char... a);
/**
*
* @param a
* @return
*/
@SequentialOnly
@IntermediateOp
public abstract CharStream appendIfEmpty(final char... a);
@SequentialOnly
@TerminalOp
public abstract CharList toCharList();
/**
*
* @param
* @param
* @param
* @param
* @param keyMapper
* @param valueMapper
* @return
* @throws E
* @throws E2
* @see Collectors#toMap(Function, Function)
*/
@ParallelSupported
@TerminalOp
public abstract Map toMap(Throwables.CharFunction keyMapper,
Throwables.CharFunction valueMapper) throws E, E2;
/**
*
* @param
* @param
* @param
* @param
* @param
* @param keyMapper
* @param valueMapper
* @param mapFactory
* @return
* @throws E
* @throws E2
* @see Collectors#toMap(Function, Function, Supplier)
*/
@ParallelSupported
@TerminalOp
public abstract , E extends Exception, E2 extends Exception> M toMap(Throwables.CharFunction keyMapper,
Throwables.CharFunction valueMapper, Supplier mapFactory) throws E, E2;
/**
*
* @param
* @param
* @param
* @param
* @param keyMapper
* @param valueMapper
* @param mergeFunction
* @return
* @throws E
* @throws E2
* @see Collectors#toMap(Function, Function, BinaryOperator)
*/
@ParallelSupported
@TerminalOp
public abstract Map toMap(Throwables.CharFunction keyMapper,
Throwables.CharFunction valueMapper, BinaryOperator mergeFunction) throws E, E2;
/**
*
* @param
* @param
* @param
* @param
* @param
* @param keyMapper
* @param valueMapper
* @param mergeFunction
* @param mapFactory
* @return
* @throws E
* @throws E2
* @see Collectors#toMap(Function, Function, BinaryOperator, Supplier)
*/
@ParallelSupported
@TerminalOp
public abstract , E extends Exception, E2 extends Exception> M toMap(Throwables.CharFunction keyMapper,
Throwables.CharFunction valueMapper, BinaryOperator mergeFunction, Supplier mapFactory) throws E, E2;
/**
*
* @param
* @param
* @param
* @param keyMapper
* @param downstream
* @return
* @throws E
* @see Collectors#groupingBy(Function, Collector)
*/
@ParallelSupported
@TerminalOp
public abstract Map groupTo(Throwables.CharFunction keyMapper,
final Collector downstream) throws E;
/**
*
* @param
* @param
* @param
* @param
* @param keyMapper
* @param downstream
* @param mapFactory
* @return
* @throws E
* @see Collectors#groupingBy(Function, Collector, Supplier)
*/
@ParallelSupported
@TerminalOp
public abstract , E extends Exception> M groupTo(Throwables.CharFunction keyMapper,
final Collector downstream, final Supplier mapFactory) throws E;
/**
* Performs a reduction on the elements of this stream, using the provided accumulator function, and returns the reduced value.
* The accumulator function takes two parameters: the current reduced value (or the initial value for the first element), and the current stream element.
*
* @param identity the initial value of the reduction operation
* @param op the function for combining the current reduced value and the current stream element
* @return the result of the reduction
* @see Stream#reduce(Object, BinaryOperator)
*/
@ParallelSupported
@TerminalOp
public abstract char reduce(char identity, CharBinaryOperator op);
/**
* Performs a reduction on the elements of this stream, using the provided accumulator function, and returns the reduced value.
* The accumulator function takes two parameters: the current reduced value and the current stream element.
*
* @param op the function for combining the current reduced value and the current stream element
* @return an OptionalChar describing the result of the reduction. If the stream is empty, an empty OptionalChar is returned.
* @see Stream#reduce(BinaryOperator)
*/
@ParallelSupported
@TerminalOp
public abstract OptionalChar reduce(CharBinaryOperator op);
/**
* Performs a mutable reduction operation on the elements of this stream using a Collector.
*
* @param The 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.
* It's unnecessary to specify {@code combiner} if {@code R} is a {@code Map/Collection/StringBuilder/Multiset/LongMultiset/Multimap/BooleanList/IntList/.../DoubleList}.
* @return the result of the reduction
* @see Stream#collect(Supplier, BiConsumer, BiConsumer)
* @see BiConsumers#ofAddAll()
* @see BiConsumers#ofPutAll()
*/
@ParallelSupported
@TerminalOp
public abstract R collect(Supplier supplier, ObjCharConsumer accumulator, BiConsumer combiner);
/**
* Performs a mutable reduction operation on the elements of this stream using a Collector.
*
*
* Only call this method when the returned type {@code R} is one types: {@code Collection/Map/StringBuilder/Multiset/LongMultiset/Multimap/BooleanList/IntList/.../DoubleList}.
* Otherwise, please call {@link #collect(Supplier, ObjCharConsumer, BiConsumer)}.
*
* @param The type of the result. It must be {@code Collection/Map/StringBuilder/Multiset/LongMultiset/Multimap/BooleanList/IntList/.../DoubleList}.
* @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.
* @throws IllegalArgumentException if the returned type {@code R} is not one of the types: {@code Collection/Map/StringBuilder/Multiset/LongMultiset/Multimap/BooleanList/IntList/.../DoubleList}.
* @return the result of the reduction
* @see #collect(Supplier, ObjCharConsumer, BiConsumer)
* @see Stream#collect(Supplier, BiConsumer)
* @see Stream#collect(Supplier, BiConsumer, BiConsumer)
*/
@ParallelSupported
@TerminalOp
public abstract R collect(Supplier supplier, ObjCharConsumer accumulator);
/**
*
* @param
* @param action
* @throws E
*/
@ParallelSupported
@TerminalOp
public abstract void forEach(final Throwables.CharConsumer action) throws E;
/**
*
* @param
* @param action
* @throws E
*/
@ParallelSupported
@TerminalOp
public abstract void forEachIndexed(Throwables.IntCharConsumer action) throws E;
/**
*
* @param
* @param predicate
* @return
* @throws E
*/
@ParallelSupported
@TerminalOp
public abstract boolean anyMatch(final Throwables.CharPredicate predicate) throws E;
/**
*
* @param
* @param predicate
* @return
* @throws E
*/
@ParallelSupported
@TerminalOp
public abstract boolean allMatch(final Throwables.CharPredicate predicate) throws E;
/**
*
* @param
* @param predicate
* @return
* @throws E
*/
@ParallelSupported
@TerminalOp
public abstract boolean noneMatch(final Throwables.CharPredicate predicate) throws E;
/**
*
* @param
* @param predicate
* @return
* @throws E
*/
@ParallelSupported
@TerminalOp
public abstract OptionalChar findFirst(final Throwables.CharPredicate predicate) throws E;
/**
*
* @param
* @param predicate
* @return
* @throws E
*/
@ParallelSupported
@TerminalOp
public abstract OptionalChar findAny(final Throwables.CharPredicate predicate) throws E;
/**
* Consider using: {@code stream.reversed().findFirst(predicate)} for better performance if possible.
*
* @param
* @param predicate
* @return
* @throws E
*/
@Beta
@ParallelSupported
@TerminalOp
public abstract OptionalChar findLast(final Throwables.CharPredicate predicate) throws E;
// /**
// * Returns the first element matched by {@code predicateForFirst} if found or the first element if this stream is not empty
// * Otherwise an empty {@code OptionalChar} will be returned.
// *
// * @param
// * @param predicateForFirst
// * @return
// * @throws E
// */
// @ParallelSupported
// @TerminalOp
// public abstract OptionalChar findFirstOrElseAny(Throwables.CharPredicate predicateForFirst) throws E;
//
// /**
// * Returns the first element matched by {@code predicateForFirst} if found or the last element if this stream is not empty
// * Otherwise an empty {@code OptionalChar} will be returned.
// *
// * @param
// * @param predicateForFirst
// * @return
// * @throws E
// */
// @ParallelSupported
// @TerminalOp
// public abstract OptionalChar findFirstOrElseLast(Throwables.CharPredicate predicateForFirst) throws E;
/**
* Returns an {@code OptionalChar} 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(Character::min);
* }
*
* This is a terminal operation.
*
* @return an {@code OptionalChar} containing the minimum element of this
* stream, or an empty {@code OptionalChar} if the stream is empty
*/
@SequentialOnly
@TerminalOp
public abstract OptionalChar min();
/**
* Returns an {@code OptionalChar} 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(Character::max);
* }
*
* This is a terminal
* operation.
*
* @return an {@code OptionalChar} containing the maximum element of this
* stream, or an empty {@code OptionalChar} if the stream is empty
*/
@SequentialOnly
@TerminalOp
public abstract OptionalChar max();
/**
* Returns the k-th largest element in the stream.
* If the stream is empty or the count of elements is less than k, an empty OptionalChar is returned.
*
* @param k the position (1-based) of the largest element to retrieve
* @return an OptionalChar containing the k-th largest element, or an empty OptionalChar if the stream is empty or the count of elements is less than k
*/
@SequentialOnly
@TerminalOp
public abstract OptionalChar kthLargest(int k);
@SequentialOnly
@TerminalOp
public abstract int sum();
@SequentialOnly
@TerminalOp
public abstract OptionalDouble average();
@SequentialOnly
@TerminalOp
public abstract CharSummaryStatistics summarize();
@SequentialOnly
@TerminalOp
public abstract Pair>> summarizeAndPercentiles();
// /**
// *
// * @param b
// * @param nextSelector a function to determine which element should be selected as next element.
// * The first parameter is selected if {@code MergeResult.TAKE_FIRST} is returned, otherwise the second parameter is selected.
// * @return
// * @deprecated replaced by {@code mergeWith(CharStream, CharBiFunction)}
// * @see #mergeWith(CharStream, CharBiFunction)
// */
// @SequentialOnly
// @IntermediateOp
// @Deprecated
// public CharStream merge(final CharStream b, final CharBiFunction nextSelector) {
// return mergeWith(b, nextSelector);
// }
/**
*
* @param b
* @param nextSelector a function to determine which element should be selected as next element.
* The first parameter is selected if {@code MergeResult.TAKE_FIRST} is returned, otherwise the second parameter is selected.
* @return
*/
@SequentialOnly
@IntermediateOp
public abstract CharStream mergeWith(final CharStream b, final CharBiFunction nextSelector);
/**
*
* @param b
* @param zipFunction
* @return
*/
@ParallelSupported
@IntermediateOp
public abstract CharStream zipWith(CharStream b, CharBinaryOperator zipFunction);
/**
*
* @param b
* @param c
* @param zipFunction
* @return
*/
@ParallelSupported
@IntermediateOp
public abstract CharStream zipWith(CharStream b, CharStream c, CharTernaryOperator zipFunction);
/**
*
* @param b
* @param valueForNoneA
* @param valueForNoneB
* @param zipFunction
* @return
*/
@ParallelSupported
@IntermediateOp
public abstract CharStream zipWith(CharStream b, char valueForNoneA, char valueForNoneB, CharBinaryOperator zipFunction);
/**
*
* @param b
* @param c
* @param valueForNoneA
* @param valueForNoneB
* @param valueForNoneC
* @param zipFunction
* @return
*/
@ParallelSupported
@IntermediateOp
public abstract CharStream zipWith(CharStream b, CharStream c, char valueForNoneA, char valueForNoneB, char valueForNoneC, CharTernaryOperator zipFunction);
/**
* Returns a {@code LongStream} consisting of the elements of this stream,
* converted to {@code long}.
*
* This is an intermediate
* operation.
*
* @return a {@code LongStream} consisting of the elements of this stream,
* converted to {@code long}
*/
@SequentialOnly
@IntermediateOp
public abstract IntStream asIntStream();
/**
* Returns a {@code Stream} consisting of the elements of this stream,
* each boxed to an {@code Character}.
*
*
This is an intermediate
* operation.
*
* @return a {@code Stream} consistent of the elements of this stream,
* each boxed to an {@code Character}
*/
@SequentialOnly
@IntermediateOp
public abstract Stream boxed();
abstract CharIteratorEx iteratorEx();
// private static final CharStream EMPTY_STREAM = new ArrayCharStream(N.EMPTY_CHAR_ARRAY, true, null);
/**
* Returns an empty CharStream.
*
* @return an empty CharStream
*/
public static CharStream empty() {
return new ArrayCharStream(N.EMPTY_CHAR_ARRAY, true, null);
}
/**
* Creates a new CharStream that is supplied by the given supplier.
* The supplier is only invoked when the stream is actually used.
* This allows for lazy evaluation of the stream.
*
* @implNote it's equivalent to {@code Stream.just(supplier).flatMapToChar(it -> it.get())}.
*
* @param supplier the supplier that provides the CharStream
* @return a new CharStream supplied by the given supplier
* @throws IllegalArgumentException if the supplier is null
* @see Stream#defer(Supplier)
*/
public static CharStream defer(final Supplier supplier) throws IllegalArgumentException {
N.checkArgNotNull(supplier, cs.supplier);
//noinspection resource
return Stream.just(supplier).flatMapToChar(Supplier::get);
}
/**
*
* @param e
* @return
*/
public static CharStream ofNullable(final Character e) {
return e == null ? empty() : of(e);
}
/**
*
* @param a
* @return
*/
@SafeVarargs
public static CharStream of(final char... a) {
return N.isEmpty(a) ? empty() : new ArrayCharStream(a);
}
/**
*
* @param a
* @param startIndex
* @param endIndex
* @return
*/
public static CharStream of(final char[] a, final int startIndex, final int endIndex) {
return N.isEmpty(a) && (startIndex == 0 && endIndex == 0) ? empty() : new ArrayCharStream(a, startIndex, endIndex);
}
/**
* Takes the chars in the specified String as the elements of the Stream.
*
* @param str
* @return
*/
public static CharStream of(final CharSequence str) {
return Strings.isEmpty(str) ? empty() : of(str, 0, str.length());
}
/**
* Takes the chars in the specified String as the elements of the Stream.
*
* @param str
* @param startIndex
* @param endIndex
* @return
* @throws IndexOutOfBoundsException
*/
public static CharStream of(final CharSequence str, final int startIndex, final int endIndex) throws IndexOutOfBoundsException {
N.checkFromToIndex(startIndex, endIndex, N.len(str));
if (Strings.isEmpty(str)) {
return empty();
}
// if (str instanceof String && IOUtil.JAVA_VERSION.atMost(JavaVersion.JAVA_1_8)) {
// return of(com.landawn.abacus.util.InternalUtil.getCharsForReadOnly((String) str), startIndex, endIndex);
// }
final CharIteratorEx iter = new CharIteratorEx() {
private int cursor = startIndex;
@Override
public boolean hasNext() {
return cursor < endIndex;
}
@Override
public char nextChar() {
return str.charAt(cursor++);
}
@Override
public long count() {
return endIndex - cursor; //NOSONAR
}
};
return new IteratorCharStream(iter);
}
/**
*
* @param a
* @return
*/
public static CharStream of(final Character[] a) {
//noinspection resource
return Stream.of(a).mapToChar(FC.unbox());
}
/**
*
* @param a
* @param startIndex
* @param endIndex
* @return
*/
public static CharStream of(final Character[] a, final int startIndex, final int endIndex) {
//noinspection resource
return Stream.of(a, startIndex, endIndex).mapToChar(FC.unbox());
}
/**
*
* @param c
* @return
*/
public static CharStream of(final Collection c) {
//noinspection resource
return Stream.of(c).mapToChar(FC.unbox());
}
/**
*
* @param iterator
* @return
*/
public static CharStream of(final CharIterator iterator) {
return iterator == null ? empty() : new IteratorCharStream(iterator);
}
/**
*
* @param buf
* @return
*/
public static CharStream of(final CharBuffer buf) {
if (buf == null) {
return empty();
}
//noinspection resource
return IntStream.range(buf.position(), buf.limit()).mapToChar(buf::get);
}
/**
*
* @param file
* @return
*/
public static CharStream of(final File file) {
return of(IOUtil.newFileReader(file), true);
}
/**
*
* @param reader
* @return
*/
public static CharStream of(final Reader reader) {
return of(reader, false);
}
/**
*
* @param reader
* @param closeReaderWhenStreamIsClosed
* @return
*/
public static CharStream of(final Reader reader, final boolean closeReaderWhenStreamIsClosed) {
if (reader == null) {
return empty();
}
final CharIterator iter = new CharIterator() {
private final char[] buf = new char[8192];
private boolean isEnd = false;
private int count = 0;
private int idx = 0;
@Override
public boolean hasNext() {
if (idx >= count && !isEnd) {
try {
count = reader.read(buf);
idx = 0;
isEnd = count <= 0;
} catch (final IOException e) {
throw new UncheckedIOException(e);
}
}
return count > idx;
}
@Override
public char nextChar() {
if (!hasNext()) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
return buf[idx++];
}
};
if (closeReaderWhenStreamIsClosed) {
//noinspection resource
return of(iter).onClose(Fn.close(reader));
} else {
return of(iter);
}
}
private static final Function flatMapper = CharStream::of;
private static final Function flattMapper = CharStream::flatten;
/**
*
* @param a
* @return
*/
public static CharStream flatten(final char[][] a) {
//noinspection resource
return N.isEmpty(a) ? empty() : Stream.of(a).flatMapToChar(flatMapper);
}
/**
*
* @param a
* @param vertically
* @return
*/
public static CharStream flatten(final char[][] a, final boolean vertically) {
if (N.isEmpty(a)) {
return empty();
} else if (a.length == 1) {
return of(a[0]);
} else if (!vertically) {
//noinspection resource
return Stream.of(a).flatMapToChar(flatMapper);
}
long n = 0;
for (final char[] e : a) {
n += N.len(e);
}
if (n == 0) {
return empty();
}
final int rows = N.len(a);
final long count = n;
final CharIterator iter = new CharIteratorEx() {
private int rowNum = 0;
private int colNum = 0;
private long cnt = 0;
@Override
public boolean hasNext() {
return cnt < count;
}
@Override
public char nextChar() {
if (cnt++ >= count) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
if (rowNum == rows) {
rowNum = 0;
colNum++;
}
while (a[rowNum] == null || colNum >= a[rowNum].length) {
if (rowNum < rows - 1) {
rowNum++;
} else {
rowNum = 0;
colNum++;
}
}
return a[rowNum++][colNum];
}
};
return of(iter);
}
/**
*
* @param a
* @param valueForAlignment element to append so there are same size of elements in all rows/columns
* @param vertically
* @return
*/
public static CharStream flatten(final char[][] a, final char valueForAlignment, final boolean vertically) {
if (N.isEmpty(a)) {
return empty();
} else if (a.length == 1) {
return of(a[0]);
}
long n = 0;
int maxLen = 0;
for (final char[] e : a) {
n += N.len(e);
maxLen = N.max(maxLen, N.len(e));
}
if (n == 0) {
return empty();
}
final int rows = N.len(a);
final int cols = maxLen;
final long count = (long) rows * cols;
CharIterator iter = null;
if (vertically) {
iter = new CharIteratorEx() {
private int rowNum = 0;
private int colNum = 0;
private long cnt = 0;
@Override
public boolean hasNext() {
return cnt < count;
}
@Override
public char nextChar() {
if (cnt++ >= count) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
if (rowNum == rows) {
rowNum = 0;
colNum++;
}
if (a[rowNum] == null || colNum >= a[rowNum].length) {
rowNum++;
return valueForAlignment;
} else {
return a[rowNum++][colNum];
}
}
};
} else {
iter = new CharIteratorEx() {
private int rowNum = 0;
private int colNum = 0;
private long cnt = 0;
@Override
public boolean hasNext() {
return cnt < count;
}
@Override
public char nextChar() {
if (cnt++ >= count) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
if (colNum >= cols) {
colNum = 0;
rowNum++;
}
if (a[rowNum] == null || colNum >= a[rowNum].length) {
colNum++;
return valueForAlignment;
} else {
return a[rowNum][colNum++];
}
}
};
}
return of(iter);
}
/**
*
* @param a
* @return
*/
public static CharStream flatten(final char[][][] a) {
//noinspection resource
return N.isEmpty(a) ? empty() : Stream.of(a).flatMapToChar(flattMapper);
}
/**
*
* @param startInclusive
* @param endExclusive
* @return
*/
public static CharStream range(final char startInclusive, final char endExclusive) {
if (startInclusive >= endExclusive) {
return empty();
}
return new IteratorCharStream(new CharIteratorEx() {
private char next = startInclusive;
private int cnt = endExclusive - startInclusive;
@Override
public boolean hasNext() {
return cnt > 0;
}
@Override
public char nextChar() {
if (cnt-- <= 0) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
return next++;
}
@Override
public void advance(final long n) {
cnt = n >= cnt ? 0 : cnt - (int) n;
next += (char) n;
}
@Override
public long count() {
return cnt;
}
@Override
public char[] toArray() {
final char[] result = new char[cnt];
for (int i = 0; i < cnt; i++) {
result[i] = next++;
}
cnt = 0;
return result;
}
});
}
/**
*
* @param startInclusive
* @param endExclusive
* @param by
* @return
*/
public static CharStream range(final char startInclusive, final char endExclusive, final int by) {
if (by == 0) {
throw new IllegalArgumentException("'by' can't be zero");
}
if (endExclusive == startInclusive || endExclusive > startInclusive != by > 0) {
return empty();
}
return new IteratorCharStream(new CharIteratorEx() {
private char next = startInclusive;
private int cnt = (endExclusive - startInclusive) / by + ((endExclusive - startInclusive) % by == 0 ? 0 : 1);
@Override
public boolean hasNext() {
return cnt > 0;
}
@Override
public char nextChar() {
if (cnt-- <= 0) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
final char result = next;
next += (char) by;
return result;
}
@Override
public void advance(final long n) {
cnt = n >= cnt ? 0 : cnt - (int) n;
next += (char) (n * by);
}
@Override
public long count() {
return cnt;
}
@Override
public char[] toArray() {
final char[] result = new char[cnt];
for (int i = 0; i < cnt; i++, next += (char) by) {
result[i] = next;
}
cnt = 0;
return result;
}
});
}
/**
*
* @param startInclusive
* @param endInclusive
* @return
*/
public static CharStream rangeClosed(final char startInclusive, final char endInclusive) {
if (startInclusive > endInclusive) {
return empty();
} else if (startInclusive == endInclusive) {
return of(startInclusive);
}
return new IteratorCharStream(new CharIteratorEx() {
private char next = startInclusive;
private int cnt = endInclusive - startInclusive + 1;
@Override
public boolean hasNext() {
return cnt > 0;
}
@Override
public char nextChar() {
if (cnt-- <= 0) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
return next++;
}
@Override
public void advance(final long n) {
cnt = n >= cnt ? 0 : cnt - (int) n;
next += (char) n;
}
@Override
public long count() {
return cnt;
}
@Override
public char[] toArray() {
final char[] result = new char[cnt];
for (int i = 0; i < cnt; i++) {
result[i] = next++;
}
cnt = 0;
return result;
}
});
}
/**
*
* @param startInclusive
* @param endInclusive
* @param by
* @return
*/
public static CharStream rangeClosed(final char startInclusive, final char endInclusive, final int 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();
}
return new IteratorCharStream(new CharIteratorEx() {
private char next = startInclusive;
private int cnt = (endInclusive - startInclusive) / by + 1;
@Override
public boolean hasNext() {
return cnt > 0;
}
@Override
public char nextChar() {
if (cnt-- <= 0) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
final char result = next;
next += (char) by;
return result;
}
@Override
public void advance(final long n) {
cnt = n >= cnt ? 0 : cnt - (int) n;
next += (char) (n * by);
}
@Override
public long count() {
return cnt;
}
@Override
public char[] toArray() {
final char[] result = new char[cnt];
for (int i = 0; i < cnt; i++, next += (char) by) {
result[i] = next;
}
cnt = 0;
return result;
}
});
}
/**
*
* @param element
* @param n
* @return
* @throws IllegalArgumentException
*/
public static CharStream repeat(final char element, final long n) throws IllegalArgumentException {
N.checkArgNotNegative(n, cs.n);
if (n == 0) {
return empty();
} else if (n < 10) {
return of(Array.repeat(element, (int) n));
}
return new IteratorCharStream(new CharIteratorEx() {
private long cnt = n;
@Override
public boolean hasNext() {
return cnt > 0;
}
@Override
public char nextChar() {
if (cnt-- <= 0) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
return element;
}
@Override
public void advance(final long n) {
cnt = n >= cnt ? 0 : cnt - (int) n;
}
@Override
public long count() {
return cnt;
}
@Override
public char[] toArray() {
final char[] result = new char[(int) cnt];
for (int i = 0; i < cnt; i++) {
result[i] = element;
}
cnt = 0;
return result;
}
});
}
public static CharStream random() {
final int mod = Character.MAX_VALUE + 1;
return generate(() -> (char) RAND.nextInt(mod));
}
/**
*
* @param startInclusive
* @param endExclusive
* @return
*/
public static CharStream random(final char startInclusive, final char endExclusive) {
if (startInclusive >= endExclusive) {
throw new IllegalArgumentException("'startInclusive' must be less than 'endExclusive'");
}
final int mod = endExclusive - startInclusive;
return generate(() -> (char) (RAND.nextInt(mod) + startInclusive));
}
/**
*
* @param candidates
* @return
*/
public static CharStream random(final char[] candidates) {
if (N.isEmpty(candidates)) {
return empty();
} else if (candidates.length == Integer.MAX_VALUE) {
throw new IllegalArgumentException();
}
final int n = candidates.length;
return generate(() -> candidates[RAND.nextInt(n)]);
}
/**
* Creates a stream that iterates using the given hasNext and next suppliers.
*
* @param hasNext a BooleanSupplier that returns {@code true} if the iteration should continue
* @param next a CharSupplier that provides the next char in the iteration
* @return a CharStream of elements generated by the iteration
* @throws IllegalArgumentException if hasNext or next is null
* @see Stream#iterate(BooleanSupplier, Supplier)
*/
public static CharStream iterate(final BooleanSupplier hasNext, final CharSupplier next) throws IllegalArgumentException {
N.checkArgNotNull(hasNext);
N.checkArgNotNull(next);
return new IteratorCharStream(new CharIteratorEx() {
private boolean hasNextVal = false;
@Override
public boolean hasNext() {
if (!hasNextVal) {
hasNextVal = hasNext.getAsBoolean();
}
return hasNextVal;
}
@Override
public char nextChar() {
if (!hasNextVal && !hasNext()) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
hasNextVal = false;
return next.getAsChar();
}
});
}
/**
* Creates a stream that iterates from an initial value, applying a function to generate subsequent values,
* and continues as long as a predicate is satisfied.
*
* @param init the initial value
* @param hasNext a BooleanSupplier that returns {@code true} if the iteration should continue
* @param f a function to apply to the previous element to generate the next element
* @return a CharStream of elements generated by the iteration
* @throws IllegalArgumentException if hasNext or f is null
* @see Stream#iterate(Object, BooleanSupplier, UnaryOperator)
*/
public static CharStream iterate(final char init, final BooleanSupplier hasNext, final CharUnaryOperator f) throws IllegalArgumentException {
N.checkArgNotNull(hasNext);
N.checkArgNotNull(f);
return new IteratorCharStream(new CharIteratorEx() {
private char cur = 0;
private boolean isFirst = true;
private boolean hasNextVal = false;
@Override
public boolean hasNext() {
if (!hasNextVal) {
hasNextVal = hasNext.getAsBoolean();
}
return hasNextVal;
}
@Override
public char nextChar() {
if (!hasNextVal && !hasNext()) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
hasNextVal = false;
if (isFirst) {
isFirst = false;
cur = init;
} else {
cur = f.applyAsChar(cur);
}
return cur;
}
});
}
/**
* Creates a stream that iterates from an initial value, applying a function to generate subsequent values,
* and continues as long as a predicate is satisfied.
*
* @param init the initial value
* @param hasNext determinate if the returned stream has next by hasNext.test(init) for first time and hasNext.test(f.apply(previous)) for remaining.
* @param f a function to apply to the previous element to generate the next element
* @return a CharStream of elements generated by the iteration
* @throws IllegalArgumentException if hasNext or f is null
* @see Stream#iterate(Object, Predicate, UnaryOperator)
*/
public static CharStream iterate(final char init, final CharPredicate hasNext, final CharUnaryOperator f) throws IllegalArgumentException {
N.checkArgNotNull(hasNext);
N.checkArgNotNull(f);
return new IteratorCharStream(new CharIteratorEx() {
private char cur = 0;
private boolean isFirst = true;
private boolean hasMore = true;
private boolean hasNextVal = false;
@Override
public boolean hasNext() {
if (!hasNextVal && hasMore) {
if (isFirst) {
isFirst = false;
hasNextVal = hasNext.test(cur = init);
} else {
hasNextVal = hasNext.test(cur = f.applyAsChar(cur));
}
if (!hasNextVal) {
hasMore = false;
}
}
return hasNextVal;
}
@Override
public char nextChar() {
if (!hasNextVal && !hasNext()) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
hasNextVal = false;
return cur;
}
});
}
/**
* Creates a stream that iterates from an initial value, applying a function to generate subsequent values.
*
* @param init the initial value
* @param f a function to apply to the previous element to generate the next element
* @return a CharStream of elements generated by the iteration
* @throws IllegalArgumentException if f is null
* @see Stream#iterate(Object, UnaryOperator)
*/
public static CharStream iterate(final char init, final CharUnaryOperator f) throws IllegalArgumentException {
N.checkArgNotNull(f);
return new IteratorCharStream(new CharIteratorEx() {
private char cur = 0;
private boolean isFirst = true;
@Override
public boolean hasNext() {
return true;
}
@Override
public char nextChar() {
if (isFirst) {
isFirst = false;
cur = init;
} else {
cur = f.applyAsChar(cur);
}
return cur;
}
});
}
/**
* Generates a CharStream using the provided CharSupplier.
* The supplier is used to generate each element of the stream.
*
* @param s the CharSupplier that provides the elements of the stream
* @return a CharStream generated by the given supplier
* @throws IllegalArgumentException if the supplier is null
* @see Stream#generate(Supplier)
*/
public static CharStream generate(final CharSupplier s) throws IllegalArgumentException {
N.checkArgNotNull(s);
return new IteratorCharStream(new CharIteratorEx() {
@Override
public boolean hasNext() {
return true;
}
@Override
public char nextChar() {
return s.getAsChar();
}
});
}
/**
* Concatenates multiple arrays of chars into a single CharStream.
*
* @param a the arrays of chars to concatenate
* @return a CharStream containing all the chars from the input arrays
* @see Stream#concat(Object[][])
*/
@SafeVarargs
public static CharStream concat(final char[]... a) {
if (N.isEmpty(a)) {
return empty();
}
return concat(Arrays.asList(a));
}
/**
* Concatenates multiple CharIterators into a single CharStream.
*
* @param a the arrays of CharIterator to concatenate
* @return a CharStream containing all the chars from the input CharIterators
* @see Stream#concat(Iterator[])
*/
@SafeVarargs
public static CharStream concat(final CharIterator... a) {
if (N.isEmpty(a)) {
return empty();
}
return concatIterators(Array.asList(a));
}
/**
* Concatenates multiple CharStreams into a single CharStream.
*
* @param a the arrays of CharStream to concatenate
* @return a CharStream containing all the chars from the input CharStreams
* @see Stream#concat(Stream[])
*/
@SafeVarargs
public static CharStream concat(final CharStream... a) {
if (N.isEmpty(a)) {
return empty();
}
return concat(Array.asList(a));
}
/**
* Concatenates a list of char array into a single CharStream.
*
* @param c the list of char array to concatenate
* @return a CharStream containing all the chars from the input list of char array
* @see Stream#concat(Object[][])
*/
@Beta
public static CharStream concat(final List c) {
if (N.isEmpty(c)) {
return empty();
}
return of(new CharIteratorEx() {
private final Iterator iter = c.iterator();
private char[] cur;
private int cursor = 0;
@Override
public boolean hasNext() {
while ((N.isEmpty(cur) || cursor >= cur.length) && iter.hasNext()) {
cur = iter.next();
cursor = 0;
}
return cur != null && cursor < cur.length;
}
@Override
public char nextChar() {
if ((cur == null || cursor >= cur.length) && !hasNext()) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
return cur[cursor++];
}
});
}
/**
* Concatenates a collection of CharStream into a single CharStream.
*
* @param streams the collection of CharStream to concatenate
* @return a CharStream containing all the chars from the input collection of CharStream
* @see Stream#concat(Collection)
*/
public static CharStream concat(final Collection streams) {
return N.isEmpty(streams) ? empty() : new IteratorCharStream(new CharIteratorEx() { //NOSONAR
private final Iterator iterators = streams.iterator();
private CharStream cur;
private CharIterator iter;
@Override
public boolean hasNext() {
while ((iter == null || !iter.hasNext()) && iterators.hasNext()) {
if (cur != null) {
cur.close();
}
cur = iterators.next();
iter = cur == null ? null : cur.iteratorEx();
}
return iter != null && iter.hasNext();
}
@Override
public char nextChar() {
if ((iter == null || !iter.hasNext()) && !hasNext()) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
return iter.nextChar();
}
}).onClose(newCloseHandler(streams));
}
/**
* Concatenates a collection of CharIterator into a single CharStream.
*
* @param charIterators the collection of CharIterator to concatenate
* @return a CharStream containing all the chars from the input collection of CharIterator
* @see Stream#concatIterators(Collection)
*/
@Beta
public static CharStream concatIterators(final Collection charIterators) {
if (N.isEmpty(charIterators)) {
return empty();
}
return new IteratorCharStream(new CharIteratorEx() {
private final Iterator iter = charIterators.iterator();
private CharIterator cur;
@Override
public boolean hasNext() {
while ((cur == null || !cur.hasNext()) && iter.hasNext()) {
cur = iter.next();
}
return cur != null && cur.hasNext();
}
@Override
public char nextChar() {
if ((cur == null || !cur.hasNext()) && !hasNext()) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
return cur.nextChar();
}
});
}
/**
* Zips two char arrays into a single CharStream until one of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction.
*
* @param a the first char array
* @param b the second char array
* @param zipFunction the function to combine elements from both arrays
* @return a CharStream containing the results of applying the zip function to the elements of the input arrays
* @see Stream#zip(Object[], Object[], BiFunction)
*/
public static CharStream zip(final char[] a, final char[] b, final CharBinaryOperator zipFunction) {
if (N.isEmpty(a) || N.isEmpty(b)) {
return empty();
}
return new IteratorCharStream(new CharIteratorEx() {
private final int len = N.min(N.len(a), N.len(b));
private int cursor = 0;
@Override
public boolean hasNext() {
return cursor < len;
}
@Override
public char nextChar() {
if (cursor >= len) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
return zipFunction.applyAsChar(a[cursor], b[cursor++]);
}
});
}
/**
* Zips three char arrays into a single CharStream until one of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction.
*
* @param a the first char array
* @param b the second char array
* @param c the third char array
* @param zipFunction the function to combine elements from all three arrays
* @return a CharStream containing the results of applying the zip function to the elements of the input arrays
* @see Stream#zip(Object[], Object[], Object[], TriFunction)
*/
public static CharStream zip(final char[] a, final char[] b, final char[] c, final CharTernaryOperator zipFunction) {
if (N.isEmpty(a) || N.isEmpty(b) || N.isEmpty(c)) {
return empty();
}
return new IteratorCharStream(new CharIteratorEx() {
private final int len = N.min(N.len(a), N.len(b), N.len(c));
private int cursor = 0;
@Override
public boolean hasNext() {
return cursor < len;
}
@Override
public char nextChar() {
if (cursor >= len) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
return zipFunction.applyAsChar(a[cursor], b[cursor], c[cursor++]);
}
});
}
/**
* Zips two CharIterators into a single CharStream until one of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction.
*
* @param a the first CharIterator
* @param b the second CharIterator
* @param zipFunction the function to combine elements from both iterators
* @return a CharStream containing the results of applying the zip function to the elements of the input iterators
* @see Stream#zip(Iterator, Iterator, BiFunction)
*/
public static CharStream zip(final CharIterator a, final CharIterator b, final CharBinaryOperator zipFunction) {
return new IteratorCharStream(new CharIteratorEx() {
private final CharIterator iterA = a == null ? CharIterator.empty() : a;
private final CharIterator iterB = b == null ? CharIterator.empty() : b;
@Override
public boolean hasNext() {
return iterA.hasNext() && iterB.hasNext();
}
@Override
public char nextChar() {
return zipFunction.applyAsChar(iterA.nextChar(), iterB.nextChar());
}
});
}
/**
* Zips three CharIterators into a single CharStream until one of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction.
*
* @param a the first CharIterator
* @param b the second CharIterator
* @param c the third CharIterator
* @param zipFunction the function to combine elements from all three iterators
* @return a CharStream containing the results of applying the zip function to the elements of the input iterators
* @see Stream#zip(Iterator, Iterator, Iterator, TriFunction)
*/
public static CharStream zip(final CharIterator a, final CharIterator b, final CharIterator c, final CharTernaryOperator zipFunction) {
return new IteratorCharStream(new CharIteratorEx() {
private final CharIterator iterA = a == null ? CharIterator.empty() : a;
private final CharIterator iterB = b == null ? CharIterator.empty() : b;
private final CharIterator iterC = c == null ? CharIterator.empty() : c;
@Override
public boolean hasNext() {
return iterA.hasNext() && iterB.hasNext() && iterC.hasNext();
}
@Override
public char nextChar() {
return zipFunction.applyAsChar(iterA.nextChar(), iterB.nextChar(), iterC.nextChar());
}
});
}
/**
* Zips two CharStreams into a single CharStream until one of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction.
*
* @param a the first CharStream
* @param b the second CharStream
* @param zipFunction the function to combine elements from both streams
* @return a CharStream containing the results of applying the zip function to the elements of the input streams
* @see Stream#zip(Stream, Stream, BiFunction)
*/
public static CharStream zip(final CharStream a, final CharStream b, final CharBinaryOperator zipFunction) {
return zip(iterate(a), iterate(b), zipFunction).onClose(newCloseHandler(a, b));
}
/**
* Zips three CharStreams into a single CharStream until one of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction.
*
* @param a the first CharStream
* @param b the second CharStream
* @param c the third CharStream
* @param zipFunction the function to combine elements from all three streams
* @return a CharStream containing the results of applying the zip function to the elements of the input streams
* @see Stream#zip(Stream, Stream, Stream, TriFunction)
*/
public static CharStream zip(final CharStream a, final CharStream b, final CharStream c, final CharTernaryOperator zipFunction) {
return zip(iterate(a), iterate(b), iterate(c), zipFunction).onClose(newCloseHandler(Array.asList(a, b, c)));
}
/**
* Zips multiple CharStreams into a single CharStream until one of them runs out of values.
* Each list of values is combined into a single value using the supplied zipFunction.
*
* @param streams the collection of CharStream to zip
* @param zipFunction the function to combine elements from all the streams
* @return a CharStream containing the results of applying the zip function to the elements of the input streams
* @see Stream#zip(Collection, Function)
*/
public static CharStream zip(final Collection streams, final CharNFunction zipFunction) {
//noinspection resource
return Stream.zip(streams, zipFunction).mapToChar(ToCharFunction.UNBOX);
}
/**
* Zips two char arrays into a single CharStream until all of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction.
* If one array runs out of values before the other, the specified valueForNoneA or valueForNoneB is used.
*
* @param a the first char array
* @param b the second char array
* @param valueForNoneA the default value to use if the first array is shorter
* @param valueForNoneB the default value to use if the second array is shorter
* @param zipFunction the function to combine elements from both arrays
* @return a CharStream containing the results of applying the zip function to the elements of the input arrays
* @see Stream#zip(Object[], Object[], Object, Object, BiFunction)
*/
public static CharStream zip(final char[] a, final char[] b, final char valueForNoneA, final char valueForNoneB, final CharBinaryOperator zipFunction) {
if (N.isEmpty(a) && N.isEmpty(b)) {
return empty();
}
return new IteratorCharStream(new CharIteratorEx() {
private final int aLen = N.len(a), bLen = N.len(b), len = N.max(aLen, bLen);
private int cursor = 0;
private char ret = 0;
@Override
public boolean hasNext() {
return cursor < len;
}
@Override
public char nextChar() {
if (cursor >= len) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
ret = zipFunction.applyAsChar(cursor < aLen ? a[cursor] : valueForNoneA, cursor < bLen ? b[cursor] : valueForNoneB);
cursor++;
return ret;
}
});
}
/**
* Zips three char arrays into a single CharStream until all of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction.
* If one array runs out of values before the other, the specified valueForNoneA, valueForNoneB or valueForNoneC is used.
*
* @param a the first char array
* @param b the second char array
* @param c the third char array
* @param valueForNoneA the default value to use if the first array is shorter
* @param valueForNoneB the default value to use if the second array is shorter
* @param valueForNoneC the default value to use if the third array is shorter
* @param zipFunction the function to combine elements from all three arrays
* @return a CharStream containing the results of applying the zip function to the elements of the input arrays
* @see Stream#zip(Object[], Object[], Object[], Object, Object, Object, TriFunction)
*/
public static CharStream zip(final char[] a, final char[] b, final char[] c, final char valueForNoneA, final char valueForNoneB, final char valueForNoneC,
final CharTernaryOperator zipFunction) {
if (N.isEmpty(a) && N.isEmpty(b) && N.isEmpty(c)) {
return empty();
}
return new IteratorCharStream(new CharIteratorEx() {
private final int aLen = N.len(a), bLen = N.len(b), cLen = N.len(c), len = N.max(aLen, bLen, cLen);
private int cursor = 0;
private char ret = 0;
@Override
public boolean hasNext() {
return cursor < len;
}
@Override
public char nextChar() {
if (cursor >= len) {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
ret = zipFunction.applyAsChar(cursor < aLen ? a[cursor] : valueForNoneA, cursor < bLen ? b[cursor] : valueForNoneB,
cursor < cLen ? c[cursor] : valueForNoneC);
cursor++;
return ret;
}
});
}
/**
* Zips two CharIterators into a single CharStream until all of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction.
* If one iterator runs out of values before the other, the specified valueForNoneA or valueForNoneB is used.
*
* @param a the first CharIterator
* @param b the second CharIterator
* @param valueForNoneA the default value to use if the first iterator is shorter
* @param valueForNoneB the default value to use if the second iterator is shorter
* @param zipFunction the function to combine elements from both iterators
* @return a CharStream containing the results of applying the zip function to the elements of the input iterators
* @see Stream#zip(Iterator, Iterator, Object, Object, BiFunction)
*/
public static CharStream zip(final CharIterator a, final CharIterator b, final char valueForNoneA, final char valueForNoneB,
final CharBinaryOperator zipFunction) {
return new IteratorCharStream(new CharIteratorEx() {
private final CharIterator iterA = a == null ? CharIterator.empty() : a;
private final CharIterator iterB = b == null ? CharIterator.empty() : b;
@Override
public boolean hasNext() {
return iterA.hasNext() || iterB.hasNext();
}
@Override
public char nextChar() {
if (iterA.hasNext()) {
return zipFunction.applyAsChar(iterA.nextChar(), iterB.hasNext() ? iterB.nextChar() : valueForNoneB);
} else {
return zipFunction.applyAsChar(valueForNoneA, iterB.nextChar());
}
}
});
}
/**
* Zips three CharIterators into a single CharStream until all of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction.
* If one iterator runs out of values before the other, the specified valueForNoneA, valueForNoneB or valueForNoneC is used.
*
* @param a the first CharIterator
* @param b the second CharIterator
* @param c the third CharIterator
* @param valueForNoneA the default value to use if the first iterator is shorter
* @param valueForNoneB the default value to use if the second iterator is shorter
* @param valueForNoneC the default value to use if the third iterator is shorter
* @param zipFunction the function to combine elements from all three iterators
* @return a CharStream containing the results of applying the zip function to the elements of the input iterators
* @see Stream#zip(Iterator, Iterator, Iterator, Object, Object, Object, TriFunction)
*/
public static CharStream zip(final CharIterator a, final CharIterator b, final CharIterator c, final char valueForNoneA, final char valueForNoneB,
final char valueForNoneC, final CharTernaryOperator zipFunction) {
return new IteratorCharStream(new CharIteratorEx() {
private final CharIterator iterA = a == null ? CharIterator.empty() : a;
private final CharIterator iterB = b == null ? CharIterator.empty() : b;
private final CharIterator iterC = c == null ? CharIterator.empty() : c;
@Override
public boolean hasNext() {
return iterA.hasNext() || iterB.hasNext() || iterC.hasNext();
}
@Override
public char nextChar() {
if (iterA.hasNext()) {
return zipFunction.applyAsChar(iterA.nextChar(), iterB.hasNext() ? iterB.nextChar() : valueForNoneB,
iterC.hasNext() ? iterC.nextChar() : valueForNoneC);
} else if (iterB.hasNext()) {
return zipFunction.applyAsChar(valueForNoneA, iterB.nextChar(), iterC.hasNext() ? iterC.nextChar() : valueForNoneC);
} else {
return zipFunction.applyAsChar(valueForNoneA, valueForNoneB, iterC.nextChar());
}
}
});
}
/**
* Zips two CharStreams into a single CharStream until all of them runs out of values.
* Each pair of values is combined into a single value using the supplied zipFunction.
* If one stream runs out of values before the other, the specified valueForNoneA or valueForNoneB is used.
*
* @param a the first CharStream
* @param b the second CharStream
* @param valueForNoneA the default value to use if the first stream is shorter
* @param valueForNoneB the default value to use if the second stream is shorter
* @param zipFunction the function to combine elements from both streams
* @return a CharStream containing the results of applying the zip function to the elements of the input streams
* @see Stream#zip(Stream, Stream, Object, Object, BiFunction)
*/
public static CharStream zip(final CharStream a, final CharStream b, final char valueForNoneA, final char valueForNoneB,
final CharBinaryOperator zipFunction) {
return zip(iterate(a), iterate(b), valueForNoneA, valueForNoneB, zipFunction).onClose(newCloseHandler(a, b));
}
/**
* Zips three CharStreams into a single CharStream until all of them runs out of values.
* Each triple of values is combined into a single value using the supplied zipFunction.
* If one stream runs out of values before the other, the specified valueForNoneA, valueForNoneB or valueForNoneC is used.
*
* @param a the first CharStream
* @param b the second CharStream
* @param c the third CharStream
* @param valueForNoneA the default value to use if the first stream is shorter
* @param valueForNoneB the default value to use if the second stream is shorter
* @param valueForNoneC the default value to use if the third stream is shorter
* @param zipFunction the function to combine elements from all three streams
* @return a CharStream containing the results of applying the zip function to the elements of the input streams
* @see Stream#zip(Stream, Stream, Stream, Object, Object, Object, TriFunction)
*/
public static CharStream zip(final CharStream a, final CharStream b, final CharStream c, final char valueForNoneA, final char valueForNoneB,
final char valueForNoneC, final CharTernaryOperator zipFunction) {
return zip(iterate(a), iterate(b), iterate(c), valueForNoneA, valueForNoneB, valueForNoneC, zipFunction)
.onClose(newCloseHandler(Array.asList(a, b, c)));
}
/**
* Zips multiple CharStreams into a single CharStream until all of them runs out of values.
* Each list of values is combined into a single value using the supplied zipFunction.
* If one stream runs out of values before the other, the specified valuesForNone is used.
*
* @param streams the collection of CharStream instances to zip
* @param valuesForNone the default value to use if the corresponding stream is shorter
* @param zipFunction the function to combine elements from all the streams
* @return a CharStream containing the results of applying the zip function to the elements of the input streams
* @see Stream#zip(Collection, List, Function)
*/
public static CharStream zip(final Collection streams, final char[] valuesForNone, final CharNFunction zipFunction) {
//noinspection resource
return Stream.zip(streams, valuesForNone, zipFunction).mapToChar(ToCharFunction.UNBOX);
}
/**
* Merges two char arrays into a single CharStream based on the provided nextSelector function.
* The nextSelector function determines which element to take next from the two arrays.
*
* @param a the first char array
* @param b the second char array
* @param nextSelector a function to determine which element should be selected as the next element.
* The first parameter is selected if {@code MergeResult.TAKE_FIRST} is returned, otherwise the second parameter is selected.
* @return a CharStream containing the merged elements from the two input arrays
* @see Stream#merge(Object[], Object[], BiFunction)
*/
public static CharStream merge(final char[] a, final char[] b, final CharBiFunction nextSelector) {
if (N.isEmpty(a)) {
return of(b);
} else if (N.isEmpty(b)) {
return of(a);
}
return new IteratorCharStream(new CharIteratorEx() {
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 char nextChar() {
if (cursorA < lenA) {
if ((cursorB >= lenB) || (nextSelector.apply(a[cursorA], b[cursorB]) == MergeResult.TAKE_FIRST)) {
return a[cursorA++];
} else {
return b[cursorB++];
}
} else if (cursorB < lenB) {
return b[cursorB++];
} else {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
}
});
}
/**
* Merges three char arrays into a single CharStream based on the provided nextSelector function.
* The nextSelector function determines which element to take next from the three arrays.
*
* @param a the first char array
* @param b the second char array
* @param c the third char array
* @param nextSelector a function to determine which element should be selected as the next element.
* The first parameter is selected if {@code MergeResult.TAKE_FIRST} is returned, otherwise the second parameter is selected.
* @return a CharStream containing the merged elements from the three input arrays
* @see Stream#merge(Object[], Object[], Object[], BiFunction)
*/
public static CharStream merge(final char[] a, final char[] b, final char[] c, final CharBiFunction nextSelector) {
//noinspection resource
return merge(merge(a, b, nextSelector).iteratorEx(), CharStream.of(c).iteratorEx(), nextSelector);
}
/**
* Merges two CharIterators into a single CharStream based on the provided nextSelector function.
* The nextSelector function determines which element to take next from the two iterators.
*
* @param a the first CharIterator
* @param b the second CharIterator
* @param nextSelector a function to determine which element should be selected as the next element.
* The first parameter is selected if {@code MergeResult.TAKE_FIRST} is returned, otherwise the second parameter is selected.
* @return a CharStream containing the merged elements from the two input iterators
* @see Stream#merge(Iterator, Iterator, BiFunction)
*/
public static CharStream merge(final CharIterator a, final CharIterator b, final CharBiFunction nextSelector) {
return new IteratorCharStream(new CharIteratorEx() {
private final CharIterator iterA = a == null ? CharIterator.empty() : a;
private final CharIterator iterB = b == null ? CharIterator.empty() : b;
private char nextA = 0;
private char nextB = 0;
private boolean hasNextA = false;
private boolean hasNextB = false;
@Override
public boolean hasNext() {
return iterA.hasNext() || iterB.hasNext() || hasNextA || hasNextB;
}
@Override
public char nextChar() {
if (hasNextA) {
if (iterB.hasNext()) {
if (nextSelector.apply(nextA, (nextB = iterB.nextChar())) == MergeResult.TAKE_FIRST) {
hasNextA = false;
hasNextB = true;
return nextA;
} else {
return nextB;
}
} else {
hasNextA = false;
return nextA;
}
} else if (hasNextB) {
if (iterA.hasNext()) {
if (nextSelector.apply((nextA = iterA.nextChar()), nextB) == MergeResult.TAKE_FIRST) {
return nextA;
} else {
hasNextA = true;
hasNextB = false;
return nextB;
}
} else {
hasNextB = false;
return nextB;
}
} else if (iterA.hasNext()) {
if (iterB.hasNext()) {
if (nextSelector.apply((nextA = iterA.nextChar()), (nextB = iterB.nextChar())) == MergeResult.TAKE_FIRST) {
hasNextB = true;
return nextA;
} else {
hasNextA = true;
return nextB;
}
} else {
return iterA.nextChar();
}
} else if (iterB.hasNext()) {
return iterB.nextChar();
} else {
throw new NoSuchElementException(ERROR_MSG_FOR_NO_SUCH_EX);
}
}
});
}
/**
* Merges three CharIterators into a single CharStream based on the provided nextSelector function.
* The nextSelector function determines which element to take next from the three iterators.
*
* @param a the first CharIterator
* @param b the second CharIterator
* @param c the third CharIterator
* @param nextSelector a function to determine which element should be selected as the next element.
* The first parameter is selected if {@code MergeResult.TAKE_FIRST} is returned, otherwise the second parameter is selected.
* @return a CharStream containing the merged elements from the three input iterators
* @see Stream#merge(Iterator, Iterator, Iterator, BiFunction)
*/
public static CharStream merge(final CharIterator a, final CharIterator b, final CharIterator c, final CharBiFunction nextSelector) {
//noinspection resource
return merge(merge(a, b, nextSelector).iteratorEx(), c, nextSelector);
}
/**
* Merges two CharStreams into a single CharStream based on the provided nextSelector function.
* The nextSelector function determines which element to take next from the two streams.
*
* @param a the first CharStream
* @param b the second CharStream
* @param nextSelector a function to determine which element should be selected as the next element.
* The first parameter is selected if {@code MergeResult.TAKE_FIRST} is returned, otherwise the second parameter is selected.
* @return a CharStream containing the merged elements from the two input streams
* @see Stream#merge(Stream, Stream, BiFunction)
*/
public static CharStream merge(final CharStream a, final CharStream b, final CharBiFunction nextSelector) {
return merge(iterate(a), iterate(b), nextSelector).onClose(newCloseHandler(a, b));
}
/**
* Merges three CharStreams into a single CharStream based on the provided nextSelector function.
* The nextSelector function determines which element to take next from the three streams.
*
* @param a the first CharStream
* @param b the second CharStream
* @param c the third CharStream
* @param nextSelector a function to determine which element should be selected as the next element.
* The first parameter is selected if {@code MergeResult.TAKE_FIRST} is returned, otherwise the second parameter is selected.
* @return a CharStream containing the merged elements from the three input streams
* @see Stream#merge(Stream, Stream, Stream, BiFunction)
*/
public static CharStream merge(final CharStream a, final CharStream b, final CharStream c, final CharBiFunction nextSelector) {
return merge(merge(a, b, nextSelector), c, nextSelector);
}
/**
* Merges a collection of CharStream into a single CharStream based on the provided nextSelector function.
* The nextSelector function determines which element to take next from the multiple streams.
*
* @param streams the collection of CharStream instances to merge
* @param nextSelector a function to determine which element should be selected as the next element.
* The first parameter is selected if {@code MergeResult.TAKE_FIRST} is returned, otherwise the second parameter is selected.
* @return a CharStream containing the merged elements from the input CharStreams
* @see Stream#merge(Collection, BiFunction)
*/
public static CharStream merge(final Collection streams, final CharBiFunction nextSelector) {
if (N.isEmpty(streams)) {
return empty();
} else if (streams.size() == 1) {
return streams.iterator().next();
} else if (streams.size() == 2) {
final Iterator iter = streams.iterator();
return merge(iter.next(), iter.next(), nextSelector);
}
final Iterator iter = streams.iterator();
CharStream result = merge(iter.next(), iter.next(), nextSelector);
while (iter.hasNext()) {
result = merge(result, iter.next(), nextSelector);
}
return result;
}
// /**
// * Merges a collection of CharStream into a single CharStream in parallel.
// * All the elements from each input CharStream will be merged into two queues by multiple threads first.
// * Then these two new queues will be merged into one CharStream in current thread.
// * This method is not totally lazy evaluation and may cause out of memory error if there are too many elements merged into the two new queues.
// * Consider using {@code merge}, which is totally lazy evaluation.
// *
// * @param streams the collection of CharStream to be merged
// * @param nextSelector a function to determine which element should be selected as next element.
// * @return a CharStream containing the merged elements from the input CharStreams
// * @see Stream#parallelMerge(Collection, BiFunction)
// */
// public static CharStream parallelMerge(final Collection streams, final CharBiFunction nextSelector) {
// return parallelMerge(streams, nextSelector, DEFAULT_MAX_THREAD_NUM);
// }
//
// /**
// * Merges a collection of CharStream into a single CharStream in parallel.
// * All the elements from each input CharStream will be merged into two queues by multiple threads first.
// * Then these two new queues will be merged into one CharStream in current thread.
// * This method is not totally lazy evaluation and may cause out of memory error if there are too many elements merged into the two new queues.
// * Consider using {@code merge}, which is totally lazy evaluation.
// *
// * @param streams the collection of CharStream to be merged
// * @param nextSelector a function to determine which element should be selected as next element.
// * @param maxThreadNum the max thread number for the parallel merge.
// * @return a CharStream containing the merged elements from the input CharStreams
// * @see Stream#parallelMerge(Collection, BiFunction, int)
// */
// public static CharStream parallelMerge(final Collection streams, final CharBiFunction nextSelector,
// final int maxThreadNum) throws IllegalArgumentException {
// N.checkArgument(maxThreadNum > 0, "'maxThreadNum' must not less than 1");
//
// if (maxThreadNum <= 1) {
// return merge(streams, nextSelector);
// } else if (N.isEmpty(streams)) {
// return empty();
// } else if (streams.size() == 1) {
// return streams.iterator().next();
// } else if (streams.size() == 2) {
// final Iterator iter = streams.iterator();
// return merge(iter.next(), iter.next(), nextSelector);
// } else if (streams.size() == 3) {
// final Iterator iter = streams.iterator();
// return merge(iter.next(), iter.next(), iter.next(), nextSelector);
// }
//
// final Supplier supplier = () -> {
// final Queue queue = N.newLinkedList();
//
// queue.addAll(streams);
//
// final Holder eHolder = new Holder<>();
// final MutableInt cnt = MutableInt.of(streams.size());
// final List> futureList = new ArrayList<>(streams.size() - 1);
//
// final int threadNum = N.min(maxThreadNum, streams.size() / 2 + 1);
//
// AsyncExecutor asyncExecutorToUse = checkAsyncExecutor(DEFAULT_ASYNC_EXECUTOR, threadNum, 0);
//
// for (int i = 0; i < threadNum; i++) {
// asyncExecutorToUse = execute(asyncExecutorToUse, threadNum, 0, i, futureList, () -> {
// CharStream a = null;
// CharStream b = null;
// CharStream c1 = null;
//
// try {
// while (eHolder.value() == null) {
// synchronized (queue) {
// if (cnt.value() > 2 && queue.size() > 1) {
// a = queue.poll();
// b = queue.poll();
//
// cnt.decrement();
// } else {
// break;
// }
// }
//
// c1 = CharStream.of(merge(a, b, nextSelector).toArray());
//
// synchronized (queue) {
// queue.offer(c1);
// }
// }
// } catch (final Throwable e) { // NOSONAR
// setError(eHolder, e);
// }
// });
// }
//
// completeAndShutdownTempExecutor(futureList, eHolder, streams, asyncExecutorToUse);
//
// return merge(queue.poll(), queue.poll(), nextSelector);
// };
//
// return Stream.just(supplier).flatMapToChar(Supplier::get);
// }
public abstract static class CharStreamEx extends CharStream {
private CharStreamEx(final boolean sorted, final Collection closeHandlers) { //NOSONAR
super(sorted, closeHandlers);
}
}
}