1240 lines
52 KiB
Java
1240 lines
52 KiB
Java
/*
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* Copyright (c) 2012, 2020, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation. Oracle designates this
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* particular file as subject to the "Classpath" exception as provided
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* by Oracle in the LICENSE file that accompanied this code.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*/
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package java.util.stream;
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import java.util.Arrays;
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import java.util.IntSummaryStatistics;
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import java.util.Objects;
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import java.util.OptionalDouble;
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import java.util.OptionalInt;
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import java.util.PrimitiveIterator;
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import java.util.Spliterator;
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import java.util.Spliterators;
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import java.util.function.BiConsumer;
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import java.util.function.Function;
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import java.util.function.IntBinaryOperator;
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import java.util.function.IntConsumer;
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import java.util.function.IntFunction;
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import java.util.function.IntPredicate;
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import java.util.function.IntSupplier;
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import java.util.function.IntToDoubleFunction;
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import java.util.function.IntToLongFunction;
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import java.util.function.IntUnaryOperator;
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import java.util.function.ObjIntConsumer;
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import java.util.function.Supplier;
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/**
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* A sequence of primitive int-valued elements supporting sequential and parallel
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* aggregate operations. This is the {@code int} primitive specialization of
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* {@link Stream}.
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*
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* <p>The following example illustrates an aggregate operation using
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* {@link Stream} and {@link IntStream}, computing the sum of the weights of the
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* red widgets:
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*
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* <pre>{@code
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* int sum = widgets.stream()
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* .filter(w -> w.getColor() == RED)
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* .mapToInt(w -> w.getWeight())
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* .sum();
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* }</pre>
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*
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* See the class documentation for {@link Stream} and the package documentation
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* for <a href="package-summary.html">java.util.stream</a> for additional
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* specification of streams, stream operations, stream pipelines, and
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* parallelism.
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*
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* @since 1.8
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* @see Stream
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* @see <a href="package-summary.html">java.util.stream</a>
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*/
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public interface IntStream extends BaseStream<Integer, IntStream> {
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/**
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* Returns a stream consisting of the elements of this stream that match
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* the given predicate.
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*
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* <p>This is an <a href="package-summary.html#StreamOps">intermediate
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* operation</a>.
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*
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* @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>,
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* <a href="package-summary.html#Statelessness">stateless</a>
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* predicate to apply to each element to determine if it
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* should be included
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* @return the new stream
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*/
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IntStream filter(IntPredicate predicate);
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/**
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* Returns a stream consisting of the results of applying the given
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* function to the elements of this stream.
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*
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* <p>This is an <a href="package-summary.html#StreamOps">intermediate
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* operation</a>.
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*
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* @param mapper a <a href="package-summary.html#NonInterference">non-interfering</a>,
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* <a href="package-summary.html#Statelessness">stateless</a>
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* function to apply to each element
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* @return the new stream
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*/
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IntStream map(IntUnaryOperator mapper);
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/**
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* Returns an object-valued {@code Stream} consisting of the results of
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* applying the given function to the elements of this stream.
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*
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* <p>This is an <a href="package-summary.html#StreamOps">
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* intermediate operation</a>.
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*
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* @param <U> the element type of the new stream
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* @param mapper a <a href="package-summary.html#NonInterference">non-interfering</a>,
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* <a href="package-summary.html#Statelessness">stateless</a>
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* function to apply to each element
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* @return the new stream
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*/
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<U> Stream<U> mapToObj(IntFunction<? extends U> mapper);
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/**
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* Returns a {@code LongStream} consisting of the results of applying the
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* given function to the elements of this stream.
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*
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* <p>This is an <a href="package-summary.html#StreamOps">intermediate
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* operation</a>.
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*
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* @param mapper a <a href="package-summary.html#NonInterference">non-interfering</a>,
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* <a href="package-summary.html#Statelessness">stateless</a>
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* function to apply to each element
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* @return the new stream
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*/
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LongStream mapToLong(IntToLongFunction mapper);
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/**
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* Returns a {@code DoubleStream} consisting of the results of applying the
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* given function to the elements of this stream.
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*
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* <p>This is an <a href="package-summary.html#StreamOps">intermediate
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* operation</a>.
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*
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* @param mapper a <a href="package-summary.html#NonInterference">non-interfering</a>,
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* <a href="package-summary.html#Statelessness">stateless</a>
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* function to apply to each element
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* @return the new stream
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*/
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DoubleStream mapToDouble(IntToDoubleFunction mapper);
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/**
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* Returns a stream consisting of the results of replacing each element of
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* this stream with the contents of a mapped stream produced by applying
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* the provided mapping function to each element. Each mapped stream is
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* {@link java.util.stream.BaseStream#close() closed} after its contents
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* have been placed into this stream. (If a mapped stream is {@code null}
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* an empty stream is used, instead.)
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*
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* <p>This is an <a href="package-summary.html#StreamOps">intermediate
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* operation</a>.
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*
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* @param mapper a <a href="package-summary.html#NonInterference">non-interfering</a>,
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* <a href="package-summary.html#Statelessness">stateless</a>
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* function to apply to each element which produces an
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* {@code IntStream} of new values
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* @return the new stream
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* @see Stream#flatMap(Function)
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*/
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IntStream flatMap(IntFunction<? extends IntStream> mapper);
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/**
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* Returns a stream consisting of the results of replacing each element of
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* this stream with multiple elements, specifically zero or more elements.
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* Replacement is performed by applying the provided mapping function to each
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* element in conjunction with a {@linkplain IntConsumer consumer} argument
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* that accepts replacement elements. The mapping function calls the consumer
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* zero or more times to provide the replacement elements.
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*
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* <p>This is an <a href="package-summary.html#StreamOps">intermediate
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* operation</a>.
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*
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* <p>If the {@linkplain IntConsumer consumer} argument is used outside the scope of
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* its application to the mapping function, the results are undefined.
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*
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* @implSpec
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* The default implementation invokes {@link #flatMap flatMap} on this stream,
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* passing a function that behaves as follows. First, it calls the mapper function
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* with an {@code IntConsumer} that accumulates replacement elements into a newly created
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* internal buffer. When the mapper function returns, it creates an {@code IntStream} from the
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* internal buffer. Finally, it returns this stream to {@code flatMap}.
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*
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* @param mapper a <a href="package-summary.html#NonInterference">non-interfering</a>,
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* <a href="package-summary.html#Statelessness">stateless</a>
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* function that generates replacement elements
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* @return the new stream
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* @see Stream#mapMulti Stream.mapMulti
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* @since 16
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*/
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default IntStream mapMulti(IntMapMultiConsumer mapper) {
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Objects.requireNonNull(mapper);
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return flatMap(e -> {
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SpinedBuffer.OfInt buffer = new SpinedBuffer.OfInt();
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mapper.accept(e, buffer);
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return StreamSupport.intStream(buffer.spliterator(), false);
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});
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}
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/**
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* Returns a stream consisting of the distinct elements of this stream.
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*
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* <p>This is a <a href="package-summary.html#StreamOps">stateful
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* intermediate operation</a>.
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*
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* @return the new stream
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*/
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IntStream distinct();
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/**
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* Returns a stream consisting of the elements of this stream in sorted
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* order.
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*
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* <p>This is a <a href="package-summary.html#StreamOps">stateful
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* intermediate operation</a>.
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*
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* @return the new stream
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*/
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IntStream sorted();
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/**
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* Returns a stream consisting of the elements of this stream, additionally
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* performing the provided action on each element as elements are consumed
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* from the resulting stream.
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*
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* <p>This is an <a href="package-summary.html#StreamOps">intermediate
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* operation</a>.
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*
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* <p>For parallel stream pipelines, the action may be called at
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* whatever time and in whatever thread the element is made available by the
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* upstream operation. If the action modifies shared state,
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* it is responsible for providing the required synchronization.
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*
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* @apiNote This method exists mainly to support debugging, where you want
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* to see the elements as they flow past a certain point in a pipeline:
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* <pre>{@code
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* IntStream.of(1, 2, 3, 4)
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* .filter(e -> e > 2)
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* .peek(e -> System.out.println("Filtered value: " + e))
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* .map(e -> e * e)
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* .peek(e -> System.out.println("Mapped value: " + e))
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* .sum();
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* }</pre>
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*
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* <p>In cases where the stream implementation is able to optimize away the
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* production of some or all the elements (such as with short-circuiting
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* operations like {@code findFirst}, or in the example described in
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* {@link #count}), the action will not be invoked for those elements.
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*
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* @param action a <a href="package-summary.html#NonInterference">
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* non-interfering</a> action to perform on the elements as
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* they are consumed from the stream
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* @return the new stream
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*/
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IntStream peek(IntConsumer action);
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/**
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* Returns a stream consisting of the elements of this stream, truncated
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* to be no longer than {@code maxSize} in length.
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*
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* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
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* stateful intermediate operation</a>.
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*
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* @apiNote
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* While {@code limit()} is generally a cheap operation on sequential
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* stream pipelines, it can be quite expensive on ordered parallel pipelines,
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* especially for large values of {@code maxSize}, since {@code limit(n)}
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* is constrained to return not just any <em>n</em> elements, but the
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* <em>first n</em> elements in the encounter order. Using an unordered
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* stream source (such as {@link #generate(IntSupplier)}) or removing the
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* ordering constraint with {@link #unordered()} may result in significant
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* speedups of {@code limit()} in parallel pipelines, if the semantics of
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* your situation permit. If consistency with encounter order is required,
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* and you are experiencing poor performance or memory utilization with
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* {@code limit()} in parallel pipelines, switching to sequential execution
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* with {@link #sequential()} may improve performance.
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*
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* @param maxSize the number of elements the stream should be limited to
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* @return the new stream
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* @throws IllegalArgumentException if {@code maxSize} is negative
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*/
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IntStream limit(long maxSize);
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/**
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* Returns a stream consisting of the remaining elements of this stream
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* after discarding the first {@code n} elements of the stream.
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* If this stream contains fewer than {@code n} elements then an
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* empty stream will be returned.
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*
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* <p>This is a <a href="package-summary.html#StreamOps">stateful
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* intermediate operation</a>.
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*
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* @apiNote
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* While {@code skip()} is generally a cheap operation on sequential
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* stream pipelines, it can be quite expensive on ordered parallel pipelines,
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* especially for large values of {@code n}, since {@code skip(n)}
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* is constrained to skip not just any <em>n</em> elements, but the
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* <em>first n</em> elements in the encounter order. Using an unordered
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* stream source (such as {@link #generate(IntSupplier)}) or removing the
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* ordering constraint with {@link #unordered()} may result in significant
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* speedups of {@code skip()} in parallel pipelines, if the semantics of
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* your situation permit. If consistency with encounter order is required,
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* and you are experiencing poor performance or memory utilization with
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* {@code skip()} in parallel pipelines, switching to sequential execution
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* with {@link #sequential()} may improve performance.
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*
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* @param n the number of leading elements to skip
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* @return the new stream
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* @throws IllegalArgumentException if {@code n} is negative
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*/
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IntStream skip(long n);
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/**
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* Returns, if this stream is ordered, a stream consisting of the longest
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* prefix of elements taken from this stream that match the given predicate.
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* Otherwise returns, if this stream is unordered, a stream consisting of a
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* subset of elements taken from this stream that match the given predicate.
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*
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* <p>If this stream is ordered then the longest prefix is a contiguous
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* sequence of elements of this stream that match the given predicate. The
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* first element of the sequence is the first element of this stream, and
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* the element immediately following the last element of the sequence does
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* not match the given predicate.
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*
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* <p>If this stream is unordered, and some (but not all) elements of this
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* stream match the given predicate, then the behavior of this operation is
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* nondeterministic; it is free to take any subset of matching elements
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* (which includes the empty set).
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*
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* <p>Independent of whether this stream is ordered or unordered if all
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* elements of this stream match the given predicate then this operation
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* takes all elements (the result is the same as the input), or if no
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* elements of the stream match the given predicate then no elements are
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* taken (the result is an empty stream).
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*
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* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
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* stateful intermediate operation</a>.
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*
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* @implSpec
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* The default implementation obtains the {@link #spliterator() spliterator}
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* of this stream, wraps that spliterator so as to support the semantics
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* of this operation on traversal, and returns a new stream associated with
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* the wrapped spliterator. The returned stream preserves the execution
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* characteristics of this stream (namely parallel or sequential execution
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* as per {@link #isParallel()}) but the wrapped spliterator may choose to
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* not support splitting. When the returned stream is closed, the close
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* handlers for both the returned and this stream are invoked.
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*
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* @apiNote
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* While {@code takeWhile()} is generally a cheap operation on sequential
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* stream pipelines, it can be quite expensive on ordered parallel
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* pipelines, since the operation is constrained to return not just any
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* valid prefix, but the longest prefix of elements in the encounter order.
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* Using an unordered stream source (such as {@link #generate(IntSupplier)})
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* or removing the ordering constraint with {@link #unordered()} may result
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* in significant speedups of {@code takeWhile()} in parallel pipelines, if
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* the semantics of your situation permit. If consistency with encounter
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* order is required, and you are experiencing poor performance or memory
|
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* utilization with {@code takeWhile()} in parallel pipelines, switching to
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* sequential execution with {@link #sequential()} may improve performance.
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*
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* @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>,
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* <a href="package-summary.html#Statelessness">stateless</a>
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* predicate to apply to elements to determine the longest
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* prefix of elements.
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* @return the new stream
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* @since 9
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*/
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default IntStream takeWhile(IntPredicate predicate) {
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Objects.requireNonNull(predicate);
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// Reuses the unordered spliterator, which, when encounter is present,
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// is safe to use as long as it configured not to split
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return StreamSupport.intStream(
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new WhileOps.UnorderedWhileSpliterator.OfInt.Taking(spliterator(), true, predicate),
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isParallel()).onClose(this::close);
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}
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/**
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* Returns, if this stream is ordered, a stream consisting of the remaining
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* elements of this stream after dropping the longest prefix of elements
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* that match the given predicate. Otherwise returns, if this stream is
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* unordered, a stream consisting of the remaining elements of this stream
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* after dropping a subset of elements that match the given predicate.
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*
|
|
* <p>If this stream is ordered then the longest prefix is a contiguous
|
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* sequence of elements of this stream that match the given predicate. The
|
|
* first element of the sequence is the first element of this stream, and
|
|
* the element immediately following the last element of the sequence does
|
|
* not match the given predicate.
|
|
*
|
|
* <p>If this stream is unordered, and some (but not all) elements of this
|
|
* stream match the given predicate, then the behavior of this operation is
|
|
* nondeterministic; it is free to drop any subset of matching elements
|
|
* (which includes the empty set).
|
|
*
|
|
* <p>Independent of whether this stream is ordered or unordered if all
|
|
* elements of this stream match the given predicate then this operation
|
|
* drops all elements (the result is an empty stream), or if no elements of
|
|
* the stream match the given predicate then no elements are dropped (the
|
|
* result is the same as the input).
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">stateful
|
|
* intermediate operation</a>.
|
|
*
|
|
* @implSpec
|
|
* The default implementation obtains the {@link #spliterator() spliterator}
|
|
* of this stream, wraps that spliterator so as to support the semantics
|
|
* of this operation on traversal, and returns a new stream associated with
|
|
* the wrapped spliterator. The returned stream preserves the execution
|
|
* characteristics of this stream (namely parallel or sequential execution
|
|
* as per {@link #isParallel()}) but the wrapped spliterator may choose to
|
|
* not support splitting. When the returned stream is closed, the close
|
|
* handlers for both the returned and this stream are invoked.
|
|
*
|
|
* @apiNote
|
|
* While {@code dropWhile()} is generally a cheap operation on sequential
|
|
* stream pipelines, it can be quite expensive on ordered parallel
|
|
* pipelines, since the operation is constrained to return not just any
|
|
* valid prefix, but the longest prefix of elements in the encounter order.
|
|
* Using an unordered stream source (such as {@link #generate(IntSupplier)})
|
|
* or removing the ordering constraint with {@link #unordered()} may result
|
|
* in significant speedups of {@code dropWhile()} in parallel pipelines, if
|
|
* the semantics of your situation permit. If consistency with encounter
|
|
* order is required, and you are experiencing poor performance or memory
|
|
* utilization with {@code dropWhile()} in parallel pipelines, switching to
|
|
* sequential execution with {@link #sequential()} may improve performance.
|
|
*
|
|
* @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>,
|
|
* <a href="package-summary.html#Statelessness">stateless</a>
|
|
* predicate to apply to elements to determine the longest
|
|
* prefix of elements.
|
|
* @return the new stream
|
|
* @since 9
|
|
*/
|
|
default IntStream dropWhile(IntPredicate predicate) {
|
|
Objects.requireNonNull(predicate);
|
|
// Reuses the unordered spliterator, which, when encounter is present,
|
|
// is safe to use as long as it configured not to split
|
|
return StreamSupport.intStream(
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|
new WhileOps.UnorderedWhileSpliterator.OfInt.Dropping(spliterator(), true, predicate),
|
|
isParallel()).onClose(this::close);
|
|
}
|
|
|
|
/**
|
|
* Performs an action for each element of this stream.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal
|
|
* operation</a>.
|
|
*
|
|
* <p>For parallel stream pipelines, this operation does <em>not</em>
|
|
* guarantee to respect the encounter order of the stream, as doing so
|
|
* would sacrifice the benefit of parallelism. For any given element, the
|
|
* action may be performed at whatever time and in whatever thread the
|
|
* library chooses. If the action accesses shared state, it is
|
|
* responsible for providing the required synchronization.
|
|
*
|
|
* @param action a <a href="package-summary.html#NonInterference">
|
|
* non-interfering</a> action to perform on the elements
|
|
*/
|
|
void forEach(IntConsumer action);
|
|
|
|
/**
|
|
* Performs an action for each element of this stream, guaranteeing that
|
|
* each element is processed in encounter order for streams that have a
|
|
* defined encounter order.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal
|
|
* operation</a>.
|
|
*
|
|
* @param action a <a href="package-summary.html#NonInterference">
|
|
* non-interfering</a> action to perform on the elements
|
|
* @see #forEach(IntConsumer)
|
|
*/
|
|
void forEachOrdered(IntConsumer action);
|
|
|
|
/**
|
|
* Returns an array containing the elements of this stream.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal
|
|
* operation</a>.
|
|
*
|
|
* @return an array containing the elements of this stream
|
|
*/
|
|
int[] toArray();
|
|
|
|
/**
|
|
* Performs a <a href="package-summary.html#Reduction">reduction</a> on the
|
|
* elements of this stream, using the provided identity value and an
|
|
* <a href="package-summary.html#Associativity">associative</a>
|
|
* accumulation function, and returns the reduced value. This is equivalent
|
|
* to:
|
|
* <pre>{@code
|
|
* int result = identity;
|
|
* for (int element : this stream)
|
|
* result = accumulator.applyAsInt(result, element)
|
|
* return result;
|
|
* }</pre>
|
|
*
|
|
* but is not constrained to execute sequentially.
|
|
*
|
|
* <p>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
|
|
* <a href="package-summary.html#Associativity">associative</a> function.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal
|
|
* operation</a>.
|
|
*
|
|
* @apiNote Sum, min and max are all special cases of reduction that can be
|
|
* expressed using this method.
|
|
* For example, summing a stream can be expressed as:
|
|
*
|
|
* <pre>{@code
|
|
* int sum = integers.reduce(0, (a, b) -> a+b);
|
|
* }</pre>
|
|
*
|
|
* or more compactly:
|
|
*
|
|
* <pre>{@code
|
|
* int sum = integers.reduce(0, Integer::sum);
|
|
* }</pre>
|
|
*
|
|
* <p>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 <a href="package-summary.html#Associativity">associative</a>,
|
|
* <a href="package-summary.html#NonInterference">non-interfering</a>,
|
|
* <a href="package-summary.html#Statelessness">stateless</a>
|
|
* function for combining two values
|
|
* @return the result of the reduction
|
|
* @see #sum()
|
|
* @see #min()
|
|
* @see #max()
|
|
* @see #average()
|
|
*/
|
|
int reduce(int identity, IntBinaryOperator op);
|
|
|
|
/**
|
|
* Performs a <a href="package-summary.html#Reduction">reduction</a> on the
|
|
* elements of this stream, using an
|
|
* <a href="package-summary.html#Associativity">associative</a> accumulation
|
|
* function, and returns an {@code OptionalInt} describing the reduced value,
|
|
* if any. This is equivalent to:
|
|
* <pre>{@code
|
|
* boolean foundAny = false;
|
|
* int result = null;
|
|
* for (int element : this stream) {
|
|
* if (!foundAny) {
|
|
* foundAny = true;
|
|
* result = element;
|
|
* }
|
|
* else
|
|
* result = accumulator.applyAsInt(result, element);
|
|
* }
|
|
* return foundAny ? OptionalInt.of(result) : OptionalInt.empty();
|
|
* }</pre>
|
|
*
|
|
* but is not constrained to execute sequentially.
|
|
*
|
|
* <p>The {@code accumulator} function must be an
|
|
* <a href="package-summary.html#Associativity">associative</a> function.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal
|
|
* operation</a>.
|
|
*
|
|
* @param op an <a href="package-summary.html#Associativity">associative</a>,
|
|
* <a href="package-summary.html#NonInterference">non-interfering</a>,
|
|
* <a href="package-summary.html#Statelessness">stateless</a>
|
|
* function for combining two values
|
|
* @return the result of the reduction
|
|
* @see #reduce(int, IntBinaryOperator)
|
|
*/
|
|
OptionalInt reduce(IntBinaryOperator op);
|
|
|
|
/**
|
|
* Performs a <a href="package-summary.html#MutableReduction">mutable
|
|
* reduction</a> 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:
|
|
* <pre>{@code
|
|
* R result = supplier.get();
|
|
* for (int element : this stream)
|
|
* accumulator.accept(result, element);
|
|
* return result;
|
|
* }</pre>
|
|
*
|
|
* <p>Like {@link #reduce(int, IntBinaryOperator)}, {@code collect} operations
|
|
* can be parallelized without requiring additional synchronization.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal
|
|
* operation</a>.
|
|
*
|
|
* @param <R> the type of the mutable result container
|
|
* @param supplier a function that creates a new mutable result container.
|
|
* For a parallel execution, this function may be called
|
|
* multiple times and must return a fresh value each time.
|
|
* @param accumulator an <a href="package-summary.html#Associativity">associative</a>,
|
|
* <a href="package-summary.html#NonInterference">non-interfering</a>,
|
|
* <a href="package-summary.html#Statelessness">stateless</a>
|
|
* function that must fold an element into a result
|
|
* container.
|
|
* @param combiner an <a href="package-summary.html#Associativity">associative</a>,
|
|
* <a href="package-summary.html#NonInterference">non-interfering</a>,
|
|
* <a href="package-summary.html#Statelessness">stateless</a>
|
|
* function that accepts two partial result containers
|
|
* and merges them, which must be compatible with the
|
|
* accumulator function. The combiner function must fold
|
|
* the elements from the second result container into the
|
|
* first result container.
|
|
* @return the result of the reduction
|
|
* @see Stream#collect(Supplier, BiConsumer, BiConsumer)
|
|
*/
|
|
<R> R collect(Supplier<R> supplier,
|
|
ObjIntConsumer<R> accumulator,
|
|
BiConsumer<R, R> combiner);
|
|
|
|
/**
|
|
* Returns the sum of elements in this stream. This is a special case
|
|
* of a <a href="package-summary.html#Reduction">reduction</a>
|
|
* and is equivalent to:
|
|
* <pre>{@code
|
|
* return reduce(0, Integer::sum);
|
|
* }</pre>
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal
|
|
* operation</a>.
|
|
*
|
|
* @return the sum of elements in this stream
|
|
*/
|
|
int sum();
|
|
|
|
/**
|
|
* Returns an {@code OptionalInt} describing the minimum element of this
|
|
* stream, or an empty optional if this stream is empty. This is a special
|
|
* case of a <a href="package-summary.html#Reduction">reduction</a>
|
|
* and is equivalent to:
|
|
* <pre>{@code
|
|
* return reduce(Integer::min);
|
|
* }</pre>
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal operation</a>.
|
|
*
|
|
* @return an {@code OptionalInt} containing the minimum element of this
|
|
* stream, or an empty {@code OptionalInt} if the stream is empty
|
|
*/
|
|
OptionalInt min();
|
|
|
|
/**
|
|
* Returns an {@code OptionalInt} describing the maximum element of this
|
|
* stream, or an empty optional if this stream is empty. This is a special
|
|
* case of a <a href="package-summary.html#Reduction">reduction</a>
|
|
* and is equivalent to:
|
|
* <pre>{@code
|
|
* return reduce(Integer::max);
|
|
* }</pre>
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal
|
|
* operation</a>.
|
|
*
|
|
* @return an {@code OptionalInt} containing the maximum element of this
|
|
* stream, or an empty {@code OptionalInt} if the stream is empty
|
|
*/
|
|
OptionalInt max();
|
|
|
|
/**
|
|
* Returns the count of elements in this stream. This is a special case of
|
|
* a <a href="package-summary.html#Reduction">reduction</a> and is
|
|
* equivalent to:
|
|
* <pre>{@code
|
|
* return mapToLong(e -> 1L).sum();
|
|
* }</pre>
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal operation</a>.
|
|
*
|
|
* @apiNote
|
|
* An implementation may choose to not execute the stream pipeline (either
|
|
* sequentially or in parallel) if it is capable of computing the count
|
|
* directly from the stream source. In such cases no source elements will
|
|
* be traversed and no intermediate operations will be evaluated.
|
|
* Behavioral parameters with side-effects, which are strongly discouraged
|
|
* except for harmless cases such as debugging, may be affected. For
|
|
* example, consider the following stream:
|
|
* <pre>{@code
|
|
* IntStream s = IntStream.of(1, 2, 3, 4);
|
|
* long count = s.peek(System.out::println).count();
|
|
* }</pre>
|
|
* The number of elements covered by the stream source is known and the
|
|
* intermediate operation, {@code peek}, does not inject into or remove
|
|
* elements from the stream (as may be the case for {@code flatMap} or
|
|
* {@code filter} operations). Thus the count is 4 and there is no need to
|
|
* execute the pipeline and, as a side-effect, print out the elements.
|
|
*
|
|
* @return the count of elements in this stream
|
|
*/
|
|
long count();
|
|
|
|
/**
|
|
* 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
|
|
* <a href="package-summary.html#Reduction">reduction</a>.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal
|
|
* operation</a>.
|
|
*
|
|
* @return an {@code OptionalDouble} containing the average element of this
|
|
* stream, or an empty optional if the stream is empty
|
|
*/
|
|
OptionalDouble average();
|
|
|
|
/**
|
|
* Returns an {@code IntSummaryStatistics} describing various
|
|
* summary data about the elements of this stream. This is a special
|
|
* case of a <a href="package-summary.html#Reduction">reduction</a>.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">terminal
|
|
* operation</a>.
|
|
*
|
|
* @return an {@code IntSummaryStatistics} describing various summary data
|
|
* about the elements of this stream
|
|
*/
|
|
IntSummaryStatistics summaryStatistics();
|
|
|
|
/**
|
|
* Returns whether any elements of this stream match the provided
|
|
* predicate. May not evaluate the predicate on all elements if not
|
|
* necessary for determining the result. If the stream is empty then
|
|
* {@code false} is returned and the predicate is not evaluated.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
|
|
* terminal operation</a>.
|
|
*
|
|
* @apiNote
|
|
* This method evaluates the <em>existential quantification</em> of the
|
|
* predicate over the elements of the stream (for some x P(x)).
|
|
*
|
|
* @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>,
|
|
* <a href="package-summary.html#Statelessness">stateless</a>
|
|
* predicate to apply to elements of this stream
|
|
* @return {@code true} if any elements of the stream match the provided
|
|
* predicate, otherwise {@code false}
|
|
*/
|
|
boolean anyMatch(IntPredicate predicate);
|
|
|
|
/**
|
|
* Returns whether all elements of this stream match the provided predicate.
|
|
* May not evaluate the predicate on all elements if not necessary for
|
|
* determining the result. If the stream is empty then {@code true} is
|
|
* returned and the predicate is not evaluated.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
|
|
* terminal operation</a>.
|
|
*
|
|
* @apiNote
|
|
* This method evaluates the <em>universal quantification</em> of the
|
|
* predicate over the elements of the stream (for all x P(x)). If the
|
|
* stream is empty, the quantification is said to be <em>vacuously
|
|
* satisfied</em> and is always {@code true} (regardless of P(x)).
|
|
*
|
|
* @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>,
|
|
* <a href="package-summary.html#Statelessness">stateless</a>
|
|
* predicate to apply to elements of this stream
|
|
* @return {@code true} if either all elements of the stream match the
|
|
* provided predicate or the stream is empty, otherwise {@code false}
|
|
*/
|
|
boolean allMatch(IntPredicate predicate);
|
|
|
|
/**
|
|
* Returns whether no elements of this stream match the provided predicate.
|
|
* May not evaluate the predicate on all elements if not necessary for
|
|
* determining the result. If the stream is empty then {@code true} is
|
|
* returned and the predicate is not evaluated.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
|
|
* terminal operation</a>.
|
|
*
|
|
* @apiNote
|
|
* This method evaluates the <em>universal quantification</em> of the
|
|
* negated predicate over the elements of the stream (for all x ~P(x)). If
|
|
* the stream is empty, the quantification is said to be vacuously satisfied
|
|
* and is always {@code true}, regardless of P(x).
|
|
*
|
|
* @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>,
|
|
* <a href="package-summary.html#Statelessness">stateless</a>
|
|
* predicate to apply to elements of this stream
|
|
* @return {@code true} if either no elements of the stream match the
|
|
* provided predicate or the stream is empty, otherwise {@code false}
|
|
*/
|
|
boolean noneMatch(IntPredicate predicate);
|
|
|
|
/**
|
|
* Returns an {@link OptionalInt} describing the first element of this
|
|
* stream, or an empty {@code OptionalInt} if the stream is empty. If the
|
|
* stream has no encounter order, then any element may be returned.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
|
|
* terminal operation</a>.
|
|
*
|
|
* @return an {@code OptionalInt} describing the first element of this stream,
|
|
* or an empty {@code OptionalInt} if the stream is empty
|
|
*/
|
|
OptionalInt findFirst();
|
|
|
|
/**
|
|
* Returns an {@link OptionalInt} describing some element of the stream, or
|
|
* an empty {@code OptionalInt} if the stream is empty.
|
|
*
|
|
* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting
|
|
* terminal operation</a>.
|
|
*
|
|
* <p>The behavior of this operation is explicitly nondeterministic; it is
|
|
* free to select any element in the stream. This is to allow for maximal
|
|
* performance in parallel operations; the cost is that multiple invocations
|
|
* on the same source may not return the same result. (If a stable result
|
|
* is desired, use {@link #findFirst()} instead.)
|
|
*
|
|
* @return an {@code OptionalInt} describing some element of this stream, or
|
|
* an empty {@code OptionalInt} if the stream is empty
|
|
* @see #findFirst()
|
|
*/
|
|
OptionalInt findAny();
|
|
|
|
/**
|
|
* Returns a {@code LongStream} consisting of the elements of this stream,
|
|
* converted to {@code long}.
|
|
*
|
|
* <p>This is an <a href="package-summary.html#StreamOps">intermediate
|
|
* operation</a>.
|
|
*
|
|
* @return a {@code LongStream} consisting of the elements of this stream,
|
|
* converted to {@code long}
|
|
*/
|
|
LongStream asLongStream();
|
|
|
|
/**
|
|
* Returns a {@code DoubleStream} consisting of the elements of this stream,
|
|
* converted to {@code double}.
|
|
*
|
|
* <p>This is an <a href="package-summary.html#StreamOps">intermediate
|
|
* operation</a>.
|
|
*
|
|
* @return a {@code DoubleStream} consisting of the elements of this stream,
|
|
* converted to {@code double}
|
|
*/
|
|
DoubleStream asDoubleStream();
|
|
|
|
/**
|
|
* Returns a {@code Stream} consisting of the elements of this stream,
|
|
* each boxed to an {@code Integer}.
|
|
*
|
|
* <p>This is an <a href="package-summary.html#StreamOps">intermediate
|
|
* operation</a>.
|
|
*
|
|
* @return a {@code Stream} consistent of the elements of this stream,
|
|
* each boxed to an {@code Integer}
|
|
*/
|
|
Stream<Integer> boxed();
|
|
|
|
@Override
|
|
IntStream sequential();
|
|
|
|
@Override
|
|
IntStream parallel();
|
|
|
|
@Override
|
|
PrimitiveIterator.OfInt iterator();
|
|
|
|
@Override
|
|
Spliterator.OfInt spliterator();
|
|
|
|
// Static factories
|
|
|
|
/**
|
|
* Returns a builder for an {@code IntStream}.
|
|
*
|
|
* @return a stream builder
|
|
*/
|
|
public static Builder builder() {
|
|
return new Streams.IntStreamBuilderImpl();
|
|
}
|
|
|
|
/**
|
|
* Returns an empty sequential {@code IntStream}.
|
|
*
|
|
* @return an empty sequential stream
|
|
*/
|
|
public static IntStream empty() {
|
|
return StreamSupport.intStream(Spliterators.emptyIntSpliterator(), false);
|
|
}
|
|
|
|
/**
|
|
* Returns a sequential {@code IntStream} containing a single element.
|
|
*
|
|
* @param t the single element
|
|
* @return a singleton sequential stream
|
|
*/
|
|
public static IntStream of(int t) {
|
|
return StreamSupport.intStream(new Streams.IntStreamBuilderImpl(t), false);
|
|
}
|
|
|
|
/**
|
|
* Returns a sequential ordered stream whose elements are the specified values.
|
|
*
|
|
* @param values the elements of the new stream
|
|
* @return the new stream
|
|
*/
|
|
public static IntStream of(int... values) {
|
|
return Arrays.stream(values);
|
|
}
|
|
|
|
/**
|
|
* Returns an infinite sequential ordered {@code IntStream} produced by iterative
|
|
* application of a function {@code f} to an initial element {@code seed},
|
|
* producing a {@code Stream} consisting of {@code seed}, {@code f(seed)},
|
|
* {@code f(f(seed))}, etc.
|
|
*
|
|
* <p>The first element (position {@code 0}) in the {@code IntStream} will be
|
|
* the provided {@code seed}. For {@code n > 0}, the element at position
|
|
* {@code n}, will be the result of applying the function {@code f} to the
|
|
* element at position {@code n - 1}.
|
|
*
|
|
* <p>The action of applying {@code f} for one element
|
|
* <a href="../concurrent/package-summary.html#MemoryVisibility"><i>happens-before</i></a>
|
|
* the action of applying {@code f} for subsequent elements. For any given
|
|
* element the action may be performed in whatever thread the library
|
|
* chooses.
|
|
*
|
|
* @param seed the initial element
|
|
* @param f a function to be applied to the previous element to produce
|
|
* a new element
|
|
* @return a new sequential {@code IntStream}
|
|
*/
|
|
public static IntStream iterate(final int seed, final IntUnaryOperator f) {
|
|
Objects.requireNonNull(f);
|
|
Spliterator.OfInt spliterator = new Spliterators.AbstractIntSpliterator(Long.MAX_VALUE,
|
|
Spliterator.ORDERED | Spliterator.IMMUTABLE | Spliterator.NONNULL) {
|
|
int prev;
|
|
boolean started;
|
|
|
|
@Override
|
|
public boolean tryAdvance(IntConsumer action) {
|
|
Objects.requireNonNull(action);
|
|
int t;
|
|
if (started)
|
|
t = f.applyAsInt(prev);
|
|
else {
|
|
t = seed;
|
|
started = true;
|
|
}
|
|
action.accept(prev = t);
|
|
return true;
|
|
}
|
|
};
|
|
return StreamSupport.intStream(spliterator, false);
|
|
}
|
|
|
|
/**
|
|
* Returns a sequential ordered {@code IntStream} produced by iterative
|
|
* application of the given {@code next} function to an initial element,
|
|
* conditioned on satisfying the given {@code hasNext} predicate. The
|
|
* stream terminates as soon as the {@code hasNext} predicate returns false.
|
|
*
|
|
* <p>{@code IntStream.iterate} should produce the same sequence of elements as
|
|
* produced by the corresponding for-loop:
|
|
* <pre>{@code
|
|
* for (int index=seed; hasNext.test(index); index = next.applyAsInt(index)) {
|
|
* ...
|
|
* }
|
|
* }</pre>
|
|
*
|
|
* <p>The resulting sequence may be empty if the {@code hasNext} predicate
|
|
* does not hold on the seed value. Otherwise the first element will be the
|
|
* supplied {@code seed} value, the next element (if present) will be the
|
|
* result of applying the {@code next} function to the {@code seed} value,
|
|
* and so on iteratively until the {@code hasNext} predicate indicates that
|
|
* the stream should terminate.
|
|
*
|
|
* <p>The action of applying the {@code hasNext} predicate to an element
|
|
* <a href="../concurrent/package-summary.html#MemoryVisibility"><i>happens-before</i></a>
|
|
* the action of applying the {@code next} function to that element. The
|
|
* action of applying the {@code next} function for one element
|
|
* <i>happens-before</i> the action of applying the {@code hasNext}
|
|
* predicate for subsequent elements. For any given element an action may
|
|
* be performed in whatever thread the library chooses.
|
|
*
|
|
* @param seed the initial element
|
|
* @param hasNext a predicate to apply to elements to determine when the
|
|
* stream must terminate.
|
|
* @param next a function to be applied to the previous element to produce
|
|
* a new element
|
|
* @return a new sequential {@code IntStream}
|
|
* @since 9
|
|
*/
|
|
public static IntStream iterate(int seed, IntPredicate hasNext, IntUnaryOperator next) {
|
|
Objects.requireNonNull(next);
|
|
Objects.requireNonNull(hasNext);
|
|
Spliterator.OfInt spliterator = new Spliterators.AbstractIntSpliterator(Long.MAX_VALUE,
|
|
Spliterator.ORDERED | Spliterator.IMMUTABLE | Spliterator.NONNULL) {
|
|
int prev;
|
|
boolean started, finished;
|
|
|
|
@Override
|
|
public boolean tryAdvance(IntConsumer action) {
|
|
Objects.requireNonNull(action);
|
|
if (finished)
|
|
return false;
|
|
int t;
|
|
if (started)
|
|
t = next.applyAsInt(prev);
|
|
else {
|
|
t = seed;
|
|
started = true;
|
|
}
|
|
if (!hasNext.test(t)) {
|
|
finished = true;
|
|
return false;
|
|
}
|
|
action.accept(prev = t);
|
|
return true;
|
|
}
|
|
|
|
@Override
|
|
public void forEachRemaining(IntConsumer action) {
|
|
Objects.requireNonNull(action);
|
|
if (finished)
|
|
return;
|
|
finished = true;
|
|
int t = started ? next.applyAsInt(prev) : seed;
|
|
while (hasNext.test(t)) {
|
|
action.accept(t);
|
|
t = next.applyAsInt(t);
|
|
}
|
|
}
|
|
};
|
|
return StreamSupport.intStream(spliterator, false);
|
|
}
|
|
|
|
/**
|
|
* Returns an infinite sequential unordered stream where each element is
|
|
* generated by the provided {@code IntSupplier}. This is suitable for
|
|
* generating constant streams, streams of random elements, etc.
|
|
*
|
|
* @param s the {@code IntSupplier} for generated elements
|
|
* @return a new infinite sequential unordered {@code IntStream}
|
|
*/
|
|
public static IntStream generate(IntSupplier s) {
|
|
Objects.requireNonNull(s);
|
|
return StreamSupport.intStream(
|
|
new StreamSpliterators.InfiniteSupplyingSpliterator.OfInt(Long.MAX_VALUE, s), false);
|
|
}
|
|
|
|
/**
|
|
* Returns a sequential ordered {@code IntStream} from {@code startInclusive}
|
|
* (inclusive) to {@code endExclusive} (exclusive) by an incremental step of
|
|
* {@code 1}.
|
|
*
|
|
* @apiNote
|
|
* <p>An equivalent sequence of increasing values can be produced
|
|
* sequentially using a {@code for} loop as follows:
|
|
* <pre>{@code
|
|
* for (int i = startInclusive; i < endExclusive ; i++) { ... }
|
|
* }</pre>
|
|
*
|
|
* @param startInclusive the (inclusive) initial value
|
|
* @param endExclusive the exclusive upper bound
|
|
* @return a sequential {@code IntStream} for the range of {@code int}
|
|
* elements
|
|
*/
|
|
public static IntStream range(int startInclusive, int endExclusive) {
|
|
if (startInclusive >= endExclusive) {
|
|
return empty();
|
|
} else {
|
|
return StreamSupport.intStream(
|
|
new Streams.RangeIntSpliterator(startInclusive, endExclusive, false), false);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Returns a sequential ordered {@code IntStream} from {@code startInclusive}
|
|
* (inclusive) to {@code endInclusive} (inclusive) by an incremental step of
|
|
* {@code 1}.
|
|
*
|
|
* @apiNote
|
|
* <p>An equivalent sequence of increasing values can be produced
|
|
* sequentially using a {@code for} loop as follows:
|
|
* <pre>{@code
|
|
* for (int i = startInclusive; i <= endInclusive ; i++) { ... }
|
|
* }</pre>
|
|
*
|
|
* @param startInclusive the (inclusive) initial value
|
|
* @param endInclusive the inclusive upper bound
|
|
* @return a sequential {@code IntStream} for the range of {@code int}
|
|
* elements
|
|
*/
|
|
public static IntStream rangeClosed(int startInclusive, int endInclusive) {
|
|
if (startInclusive > endInclusive) {
|
|
return empty();
|
|
} else {
|
|
return StreamSupport.intStream(
|
|
new Streams.RangeIntSpliterator(startInclusive, endInclusive, true), false);
|
|
}
|
|
}
|
|
|
|
/**
|
|
* Creates a lazily concatenated stream whose elements are all the
|
|
* elements of the first stream followed by all the elements of the
|
|
* second stream. The resulting stream is ordered if both
|
|
* of the input streams are ordered, and parallel if either of the input
|
|
* streams is parallel. When the resulting stream is closed, the close
|
|
* handlers for both input streams are invoked.
|
|
*
|
|
* <p>This method operates on the two input streams and binds each stream
|
|
* to its source. As a result subsequent modifications to an input stream
|
|
* source may not be reflected in the concatenated stream result.
|
|
*
|
|
* @implNote
|
|
* Use caution when constructing streams from repeated concatenation.
|
|
* Accessing an element of a deeply concatenated stream can result in deep
|
|
* call chains, or even {@code StackOverflowError}.
|
|
*
|
|
* @apiNote
|
|
* To preserve optimization opportunities this method binds each stream to
|
|
* its source and accepts only two streams as parameters. For example, the
|
|
* exact size of the concatenated stream source can be computed if the exact
|
|
* size of each input stream source is known.
|
|
* To concatenate more streams without binding, or without nested calls to
|
|
* this method, try creating a stream of streams and flat-mapping with the
|
|
* identity function, for example:
|
|
* <pre>{@code
|
|
* IntStream concat = Stream.of(s1, s2, s3, s4).flatMapToInt(s -> s);
|
|
* }</pre>
|
|
*
|
|
* @param a the first stream
|
|
* @param b the second stream
|
|
* @return the concatenation of the two input streams
|
|
*/
|
|
public static IntStream concat(IntStream a, IntStream b) {
|
|
Objects.requireNonNull(a);
|
|
Objects.requireNonNull(b);
|
|
|
|
Spliterator.OfInt split = new Streams.ConcatSpliterator.OfInt(
|
|
a.spliterator(), b.spliterator());
|
|
IntStream stream = StreamSupport.intStream(split, a.isParallel() || b.isParallel());
|
|
return stream.onClose(Streams.composedClose(a, b));
|
|
}
|
|
|
|
/**
|
|
* A mutable builder for an {@code IntStream}.
|
|
*
|
|
* <p>A stream builder has a lifecycle, which starts in a building
|
|
* phase, during which elements can be added, and then transitions to a built
|
|
* phase, after which elements may not be added. The built phase
|
|
* begins when the {@link #build()} method is called, which creates an
|
|
* ordered stream whose elements are the elements that were added to the
|
|
* stream builder, in the order they were added.
|
|
*
|
|
* @see IntStream#builder()
|
|
* @since 1.8
|
|
*/
|
|
public interface Builder extends IntConsumer {
|
|
|
|
/**
|
|
* Adds an element to the stream being built.
|
|
*
|
|
* @throws IllegalStateException if the builder has already transitioned
|
|
* to the built state
|
|
*/
|
|
@Override
|
|
void accept(int t);
|
|
|
|
/**
|
|
* Adds an element to the stream being built.
|
|
*
|
|
* @implSpec
|
|
* The default implementation behaves as if:
|
|
* <pre>{@code
|
|
* accept(t)
|
|
* return this;
|
|
* }</pre>
|
|
*
|
|
* @param t the element to add
|
|
* @return {@code this} builder
|
|
* @throws IllegalStateException if the builder has already transitioned
|
|
* to the built state
|
|
*/
|
|
default Builder add(int t) {
|
|
accept(t);
|
|
return this;
|
|
}
|
|
|
|
/**
|
|
* Builds the stream, transitioning this builder to the built state.
|
|
* An {@code IllegalStateException} is thrown if there are further
|
|
* attempts to operate on the builder after it has entered the built
|
|
* state.
|
|
*
|
|
* @return the built stream
|
|
* @throws IllegalStateException if the builder has already transitioned to
|
|
* the built state
|
|
*/
|
|
IntStream build();
|
|
}
|
|
|
|
/**
|
|
* Represents an operation that accepts an {@code int}-valued argument
|
|
* and an IntConsumer, and returns no result. This functional interface is
|
|
* used by {@link IntStream#mapMulti(IntMapMultiConsumer) IntStream.mapMulti}
|
|
* to replace an int value with zero or more int values.
|
|
*
|
|
* <p>This is a <a href="../function/package-summary.html">functional interface</a>
|
|
* whose functional method is {@link #accept(int, IntConsumer)}.
|
|
*
|
|
* @see IntStream#mapMulti(IntMapMultiConsumer)
|
|
*
|
|
* @since 16
|
|
*/
|
|
@FunctionalInterface
|
|
interface IntMapMultiConsumer {
|
|
|
|
/**
|
|
* Replaces the given {@code value} with zero or more values by feeding the mapped
|
|
* values to the {@code ic} consumer.
|
|
*
|
|
* @param value the int value coming from upstream
|
|
* @param ic an {@code IntConsumer} accepting the mapped values
|
|
*/
|
|
void accept(int value, IntConsumer ic);
|
|
}
|
|
}
|