author | mchung |
Fri, 22 May 2015 16:43:39 -0700 | |
changeset 30789 | 9eca83469588 |
parent 29489 | fe7624d92790 |
child 31644 | dbca10d053fd |
permissions | -rw-r--r-- |
17167 | 1 |
/* |
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* Copyright (c) 2013, 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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||
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import java.nio.charset.Charset; |
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import java.nio.file.Files; |
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import java.nio.file.Path; |
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import java.util.Arrays; |
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import java.util.Collection; |
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import java.util.LongSummaryStatistics; |
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import java.util.Objects; |
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import java.util.OptionalDouble; |
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import java.util.OptionalLong; |
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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.concurrent.ConcurrentHashMap; |
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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.LongBinaryOperator; |
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import java.util.function.LongConsumer; |
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import java.util.function.LongFunction; |
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import java.util.function.LongPredicate; |
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import java.util.function.LongSupplier; |
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import java.util.function.LongToDoubleFunction; |
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import java.util.function.LongToIntFunction; |
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import java.util.function.LongUnaryOperator; |
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import java.util.function.ObjLongConsumer; |
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import java.util.function.Supplier; |
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/** |
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* A sequence of primitive long-valued elements supporting sequential and parallel |
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* aggregate operations. This is the {@code long} 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 LongStream}, 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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* long sum = widgets.stream() |
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* .filter(w -> w.getColor() == RED) |
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* .mapToLong(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 LongStream extends BaseStream<Long, LongStream> { |
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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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LongStream filter(LongPredicate 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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LongStream map(LongUnaryOperator 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(LongFunction<? extends U> mapper); |
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/** |
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* Returns an {@code IntStream} 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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IntStream mapToInt(LongToIntFunction 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(LongToDoubleFunction 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 a |
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* {@code LongStream} 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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LongStream flatMap(LongFunction<? extends LongStream> mapper); |
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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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LongStream 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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LongStream 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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* LongStream.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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* @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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LongStream peek(LongConsumer 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(LongSupplier)}) 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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LongStream 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(LongSupplier)}) 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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LongStream skip(long n); |
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/** |
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* Performs an action for each element of this stream. |
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* |
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* <p>This is a <a href="package-summary.html#StreamOps">terminal |
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* operation</a>. |
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* |
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* <p>For parallel stream pipelines, this operation does <em>not</em> |
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* guarantee to respect the encounter order of the stream, as doing so |
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* would sacrifice the benefit of parallelism. For any given element, the |
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* action may be performed at whatever time and in whatever thread the |
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* library chooses. If the action accesses shared state, it is |
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* responsible for providing the required synchronization. |
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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 |
|
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*/ |
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void forEach(LongConsumer action); |
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/** |
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* Performs an action for each element of this stream, guaranteeing that |
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* each element is processed in encounter order for streams that have a |
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* defined encounter order. |
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* |
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* <p>This is a <a href="package-summary.html#StreamOps">terminal |
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* operation</a>. |
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* |
|
306 |
* @param action a <a href="package-summary.html#NonInterference"> |
|
307 |
* non-interfering</a> action to perform on the elements |
|
308 |
* @see #forEach(LongConsumer) |
|
309 |
*/ |
|
310 |
void forEachOrdered(LongConsumer action); |
|
311 |
||
312 |
/** |
|
313 |
* Returns an array containing the elements of this stream. |
|
314 |
* |
|
315 |
* <p>This is a <a href="package-summary.html#StreamOps">terminal |
|
316 |
* operation</a>. |
|
317 |
* |
|
318 |
* @return an array containing the elements of this stream |
|
319 |
*/ |
|
320 |
long[] toArray(); |
|
321 |
||
322 |
/** |
|
323 |
* Performs a <a href="package-summary.html#Reduction">reduction</a> on the |
|
324 |
* elements of this stream, using the provided identity value and an |
|
325 |
* <a href="package-summary.html#Associativity">associative</a> |
|
326 |
* accumulation function, and returns the reduced value. This is equivalent |
|
327 |
* to: |
|
328 |
* <pre>{@code |
|
329 |
* long result = identity; |
|
330 |
* for (long element : this stream) |
|
22996
0ce70f4ef909
8029944: Primitive Stream reduce method documentation pseudo code misidentifies apply method
michaelm
parents:
22352
diff
changeset
|
331 |
* result = accumulator.applyAsLong(result, element) |
17167 | 332 |
* return result; |
333 |
* }</pre> |
|
334 |
* |
|
335 |
* but is not constrained to execute sequentially. |
|
336 |
* |
|
337 |
* <p>The {@code identity} value must be an identity for the accumulator |
|
338 |
* function. This means that for all {@code x}, |
|
339 |
* {@code accumulator.apply(identity, x)} is equal to {@code x}. |
|
340 |
* The {@code accumulator} function must be an |
|
341 |
* <a href="package-summary.html#Associativity">associative</a> function. |
|
342 |
* |
|
343 |
* <p>This is a <a href="package-summary.html#StreamOps">terminal |
|
344 |
* operation</a>. |
|
345 |
* |
|
346 |
* @apiNote Sum, min, max, and average are all special cases of reduction. |
|
347 |
* Summing a stream of numbers can be expressed as: |
|
348 |
* |
|
349 |
* <pre>{@code |
|
350 |
* long sum = integers.reduce(0, (a, b) -> a+b); |
|
351 |
* }</pre> |
|
352 |
* |
|
353 |
* or more compactly: |
|
354 |
* |
|
355 |
* <pre>{@code |
|
356 |
* long sum = integers.reduce(0, Long::sum); |
|
357 |
* }</pre> |
|
358 |
* |
|
359 |
* <p>While this may seem a more roundabout way to perform an aggregation |
|
360 |
* compared to simply mutating a running total in a loop, reduction |
|
361 |
* operations parallelize more gracefully, without needing additional |
|
362 |
* synchronization and with greatly reduced risk of data races. |
|
363 |
* |
|
364 |
* @param identity the identity value for the accumulating function |
|
21339 | 365 |
* @param op an <a href="package-summary.html#Associativity">associative</a>, |
366 |
* <a href="package-summary.html#NonInterference">non-interfering</a>, |
|
367 |
* <a href="package-summary.html#Statelessness">stateless</a> |
|
368 |
* function for combining two values |
|
17167 | 369 |
* @return the result of the reduction |
370 |
* @see #sum() |
|
371 |
* @see #min() |
|
372 |
* @see #max() |
|
373 |
* @see #average() |
|
374 |
*/ |
|
375 |
long reduce(long identity, LongBinaryOperator op); |
|
376 |
||
377 |
/** |
|
378 |
* Performs a <a href="package-summary.html#Reduction">reduction</a> on the |
|
379 |
* elements of this stream, using an |
|
380 |
* <a href="package-summary.html#Associativity">associative</a> accumulation |
|
381 |
* function, and returns an {@code OptionalLong} describing the reduced value, |
|
382 |
* if any. This is equivalent to: |
|
383 |
* <pre>{@code |
|
384 |
* boolean foundAny = false; |
|
385 |
* long result = null; |
|
386 |
* for (long element : this stream) { |
|
387 |
* if (!foundAny) { |
|
388 |
* foundAny = true; |
|
389 |
* result = element; |
|
390 |
* } |
|
391 |
* else |
|
22996
0ce70f4ef909
8029944: Primitive Stream reduce method documentation pseudo code misidentifies apply method
michaelm
parents:
22352
diff
changeset
|
392 |
* result = accumulator.applyAsLong(result, element); |
17167 | 393 |
* } |
394 |
* return foundAny ? OptionalLong.of(result) : OptionalLong.empty(); |
|
395 |
* }</pre> |
|
396 |
* |
|
397 |
* but is not constrained to execute sequentially. |
|
398 |
* |
|
399 |
* <p>The {@code accumulator} function must be an |
|
400 |
* <a href="package-summary.html#Associativity">associative</a> function. |
|
401 |
* |
|
402 |
* <p>This is a <a href="package-summary.html#StreamOps">terminal |
|
403 |
* operation</a>. |
|
404 |
* |
|
21339 | 405 |
* @param op an <a href="package-summary.html#Associativity">associative</a>, |
406 |
* <a href="package-summary.html#NonInterference">non-interfering</a>, |
|
407 |
* <a href="package-summary.html#Statelessness">stateless</a> |
|
408 |
* function for combining two values |
|
17167 | 409 |
* @return the result of the reduction |
410 |
* @see #reduce(long, LongBinaryOperator) |
|
411 |
*/ |
|
412 |
OptionalLong reduce(LongBinaryOperator op); |
|
413 |
||
414 |
/** |
|
415 |
* Performs a <a href="package-summary.html#MutableReduction">mutable |
|
416 |
* reduction</a> operation on the elements of this stream. A mutable |
|
19850 | 417 |
* reduction is one in which the reduced value is a mutable result container, |
17167 | 418 |
* such as an {@code ArrayList}, and elements are incorporated by updating |
19850 | 419 |
* the state of the result rather than by replacing the result. This |
17167 | 420 |
* produces a result equivalent to: |
421 |
* <pre>{@code |
|
19850 | 422 |
* R result = supplier.get(); |
17167 | 423 |
* for (long element : this stream) |
424 |
* accumulator.accept(result, element); |
|
425 |
* return result; |
|
426 |
* }</pre> |
|
427 |
* |
|
428 |
* <p>Like {@link #reduce(long, LongBinaryOperator)}, {@code collect} operations |
|
429 |
* can be parallelized without requiring additional synchronization. |
|
430 |
* |
|
431 |
* <p>This is a <a href="package-summary.html#StreamOps">terminal |
|
432 |
* operation</a>. |
|
433 |
* |
|
434 |
* @param <R> type of the result |
|
19850 | 435 |
* @param supplier a function that creates a new result container. For a |
436 |
* parallel execution, this function may be called |
|
437 |
* multiple times and must return a fresh value each time. |
|
21339 | 438 |
* @param accumulator an <a href="package-summary.html#Associativity">associative</a>, |
439 |
* <a href="package-summary.html#NonInterference">non-interfering</a>, |
|
440 |
* <a href="package-summary.html#Statelessness">stateless</a> |
|
441 |
* function for incorporating an additional element into a result |
|
442 |
* @param combiner an <a href="package-summary.html#Associativity">associative</a>, |
|
443 |
* <a href="package-summary.html#NonInterference">non-interfering</a>, |
|
444 |
* <a href="package-summary.html#Statelessness">stateless</a> |
|
445 |
* function for combining two values, which must be |
|
446 |
* compatible with the accumulator function |
|
17167 | 447 |
* @return the result of the reduction |
448 |
* @see Stream#collect(Supplier, BiConsumer, BiConsumer) |
|
449 |
*/ |
|
19850 | 450 |
<R> R collect(Supplier<R> supplier, |
17167 | 451 |
ObjLongConsumer<R> accumulator, |
452 |
BiConsumer<R, R> combiner); |
|
453 |
||
454 |
/** |
|
455 |
* Returns the sum of elements in this stream. This is a special case |
|
19850 | 456 |
* of a <a href="package-summary.html#Reduction">reduction</a> |
17167 | 457 |
* and is equivalent to: |
458 |
* <pre>{@code |
|
459 |
* return reduce(0, Long::sum); |
|
460 |
* }</pre> |
|
461 |
* |
|
19850 | 462 |
* <p>This is a <a href="package-summary.html#StreamOps">terminal |
463 |
* operation</a>. |
|
464 |
* |
|
17167 | 465 |
* @return the sum of elements in this stream |
466 |
*/ |
|
467 |
long sum(); |
|
468 |
||
469 |
/** |
|
470 |
* Returns an {@code OptionalLong} describing the minimum element of this |
|
471 |
* stream, or an empty optional if this stream is empty. This is a special |
|
19850 | 472 |
* case of a <a href="package-summary.html#Reduction">reduction</a> |
17167 | 473 |
* and is equivalent to: |
474 |
* <pre>{@code |
|
475 |
* return reduce(Long::min); |
|
476 |
* }</pre> |
|
477 |
* |
|
478 |
* <p>This is a <a href="package-summary.html#StreamOps">terminal operation</a>. |
|
479 |
* |
|
480 |
* @return an {@code OptionalLong} containing the minimum element of this |
|
481 |
* stream, or an empty {@code OptionalLong} if the stream is empty |
|
482 |
*/ |
|
483 |
OptionalLong min(); |
|
484 |
||
485 |
/** |
|
486 |
* Returns an {@code OptionalLong} describing the maximum element of this |
|
487 |
* stream, or an empty optional if this stream is empty. This is a special |
|
19850 | 488 |
* case of a <a href="package-summary.html#Reduction">reduction</a> |
17167 | 489 |
* and is equivalent to: |
490 |
* <pre>{@code |
|
491 |
* return reduce(Long::max); |
|
492 |
* }</pre> |
|
493 |
* |
|
494 |
* <p>This is a <a href="package-summary.html#StreamOps">terminal |
|
495 |
* operation</a>. |
|
496 |
* |
|
497 |
* @return an {@code OptionalLong} containing the maximum element of this |
|
498 |
* stream, or an empty {@code OptionalLong} if the stream is empty |
|
499 |
*/ |
|
500 |
OptionalLong max(); |
|
501 |
||
502 |
/** |
|
503 |
* Returns the count of elements in this stream. This is a special case of |
|
19850 | 504 |
* a <a href="package-summary.html#Reduction">reduction</a> and is |
17167 | 505 |
* equivalent to: |
506 |
* <pre>{@code |
|
507 |
* return map(e -> 1L).sum(); |
|
508 |
* }</pre> |
|
509 |
* |
|
510 |
* <p>This is a <a href="package-summary.html#StreamOps">terminal operation</a>. |
|
511 |
* |
|
29489 | 512 |
* @apiNote |
513 |
* An implementation may choose to not execute the stream pipeline (either |
|
514 |
* sequentially or in parallel) if it is capable of computing the count |
|
515 |
* directly from the stream source. In such cases no source elements will |
|
516 |
* be traversed and no intermediate operations will be evaluated. |
|
517 |
* Behavioral parameters with side-effects, which are strongly discouraged |
|
518 |
* except for harmless cases such as debugging, may be affected. For |
|
519 |
* example, consider the following stream: |
|
520 |
* <pre>{@code |
|
521 |
* LongStream s = LongStream.of(1, 2, 3, 4); |
|
522 |
* long count = s.peek(System.out::println).count(); |
|
523 |
* }</pre> |
|
524 |
* The number of elements covered by the stream source is known and the |
|
525 |
* intermediate operation, {@code peek}, does not inject into or remove |
|
526 |
* elements from the stream (as may be the case for {@code flatMap} or |
|
527 |
* {@code filter} operations). Thus the count is 4 and there is no need to |
|
528 |
* execute the pipeline and, as a side-effect, print out the elements. |
|
529 |
* |
|
17167 | 530 |
* @return the count of elements in this stream |
531 |
*/ |
|
532 |
long count(); |
|
533 |
||
534 |
/** |
|
19214
e5901820c3c1
8015318: Extend Collector with 'finish' operation
briangoetz
parents:
18825
diff
changeset
|
535 |
* Returns an {@code OptionalDouble} describing the arithmetic mean of elements of |
17167 | 536 |
* this stream, or an empty optional if this stream is empty. This is a |
537 |
* special case of a |
|
19850 | 538 |
* <a href="package-summary.html#Reduction">reduction</a>. |
539 |
* |
|
540 |
* <p>This is a <a href="package-summary.html#StreamOps">terminal |
|
541 |
* operation</a>. |
|
17167 | 542 |
* |
543 |
* @return an {@code OptionalDouble} containing the average element of this |
|
544 |
* stream, or an empty optional if the stream is empty |
|
545 |
*/ |
|
546 |
OptionalDouble average(); |
|
547 |
||
548 |
/** |
|
549 |
* Returns a {@code LongSummaryStatistics} describing various summary data |
|
550 |
* about the elements of this stream. This is a special case of a |
|
19850 | 551 |
* <a href="package-summary.html#Reduction">reduction</a>. |
552 |
* |
|
553 |
* <p>This is a <a href="package-summary.html#StreamOps">terminal |
|
554 |
* operation</a>. |
|
17167 | 555 |
* |
556 |
* @return a {@code LongSummaryStatistics} describing various summary data |
|
557 |
* about the elements of this stream |
|
558 |
*/ |
|
559 |
LongSummaryStatistics summaryStatistics(); |
|
560 |
||
561 |
/** |
|
562 |
* Returns whether any elements of this stream match the provided |
|
563 |
* predicate. May not evaluate the predicate on all elements if not |
|
21339 | 564 |
* necessary for determining the result. If the stream is empty then |
565 |
* {@code false} is returned and the predicate is not evaluated. |
|
17167 | 566 |
* |
567 |
* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting |
|
568 |
* terminal operation</a>. |
|
569 |
* |
|
21339 | 570 |
* @apiNote |
571 |
* This method evaluates the <em>existential quantification</em> of the |
|
572 |
* predicate over the elements of the stream (for some x P(x)). |
|
573 |
* |
|
574 |
* @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>, |
|
575 |
* <a href="package-summary.html#Statelessness">stateless</a> |
|
576 |
* predicate to apply to elements of this stream |
|
17167 | 577 |
* @return {@code true} if any elements of the stream match the provided |
21339 | 578 |
* predicate, otherwise {@code false} |
17167 | 579 |
*/ |
580 |
boolean anyMatch(LongPredicate predicate); |
|
581 |
||
582 |
/** |
|
583 |
* Returns whether all elements of this stream match the provided predicate. |
|
584 |
* May not evaluate the predicate on all elements if not necessary for |
|
21339 | 585 |
* determining the result. If the stream is empty then {@code true} is |
586 |
* returned and the predicate is not evaluated. |
|
17167 | 587 |
* |
588 |
* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting |
|
589 |
* terminal operation</a>. |
|
590 |
* |
|
21339 | 591 |
* @apiNote |
592 |
* This method evaluates the <em>universal quantification</em> of the |
|
593 |
* predicate over the elements of the stream (for all x P(x)). If the |
|
594 |
* stream is empty, the quantification is said to be <em>vacuously |
|
595 |
* satisfied</em> and is always {@code true} (regardless of P(x)). |
|
596 |
* |
|
597 |
* @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>, |
|
598 |
* <a href="package-summary.html#Statelessness">stateless</a> |
|
599 |
* predicate to apply to elements of this stream |
|
600 |
* @return {@code true} if either all elements of the stream match the |
|
601 |
* provided predicate or the stream is empty, otherwise {@code false} |
|
17167 | 602 |
*/ |
603 |
boolean allMatch(LongPredicate predicate); |
|
604 |
||
605 |
/** |
|
21339 | 606 |
* Returns whether no elements of this stream match the provided predicate. |
17167 | 607 |
* May not evaluate the predicate on all elements if not necessary for |
21339 | 608 |
* determining the result. If the stream is empty then {@code true} is |
609 |
* returned and the predicate is not evaluated. |
|
17167 | 610 |
* |
611 |
* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting |
|
612 |
* terminal operation</a>. |
|
613 |
* |
|
21339 | 614 |
* @apiNote |
615 |
* This method evaluates the <em>universal quantification</em> of the |
|
616 |
* negated predicate over the elements of the stream (for all x ~P(x)). If |
|
617 |
* the stream is empty, the quantification is said to be vacuously satisfied |
|
618 |
* and is always {@code true}, regardless of P(x). |
|
619 |
* |
|
620 |
* @param predicate a <a href="package-summary.html#NonInterference">non-interfering</a>, |
|
621 |
* <a href="package-summary.html#Statelessness">stateless</a> |
|
622 |
* predicate to apply to elements of this stream |
|
623 |
* @return {@code true} if either no elements of the stream match the |
|
624 |
* provided predicate or the stream is empty, otherwise {@code false} |
|
17167 | 625 |
*/ |
626 |
boolean noneMatch(LongPredicate predicate); |
|
627 |
||
628 |
/** |
|
629 |
* Returns an {@link OptionalLong} describing the first element of this |
|
19850 | 630 |
* stream, or an empty {@code OptionalLong} if the stream is empty. If the |
631 |
* stream has no encounter order, then any element may be returned. |
|
17167 | 632 |
* |
633 |
* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting |
|
634 |
* terminal operation</a>. |
|
635 |
* |
|
636 |
* @return an {@code OptionalLong} describing the first element of this |
|
637 |
* stream, or an empty {@code OptionalLong} if the stream is empty |
|
638 |
*/ |
|
639 |
OptionalLong findFirst(); |
|
640 |
||
641 |
/** |
|
642 |
* Returns an {@link OptionalLong} describing some element of the stream, or |
|
643 |
* an empty {@code OptionalLong} if the stream is empty. |
|
644 |
* |
|
645 |
* <p>This is a <a href="package-summary.html#StreamOps">short-circuiting |
|
646 |
* terminal operation</a>. |
|
647 |
* |
|
648 |
* <p>The behavior of this operation is explicitly nondeterministic; it is |
|
649 |
* free to select any element in the stream. This is to allow for maximal |
|
650 |
* performance in parallel operations; the cost is that multiple invocations |
|
19850 | 651 |
* on the same source may not return the same result. (If a stable result |
652 |
* is desired, use {@link #findFirst()} instead.) |
|
17167 | 653 |
* |
654 |
* @return an {@code OptionalLong} describing some element of this stream, |
|
655 |
* or an empty {@code OptionalLong} if the stream is empty |
|
656 |
* @see #findFirst() |
|
657 |
*/ |
|
658 |
OptionalLong findAny(); |
|
659 |
||
660 |
/** |
|
661 |
* Returns a {@code DoubleStream} consisting of the elements of this stream, |
|
662 |
* converted to {@code double}. |
|
663 |
* |
|
19850 | 664 |
* <p>This is an <a href="package-summary.html#StreamOps">intermediate |
665 |
* operation</a>. |
|
666 |
* |
|
17167 | 667 |
* @return a {@code DoubleStream} consisting of the elements of this stream, |
668 |
* converted to {@code double} |
|
669 |
*/ |
|
18154
5ede18269905
8015798: Rename IntStream.longs/doubles and LongStream.doubles to asXxxStream
psandoz
parents:
17914
diff
changeset
|
670 |
DoubleStream asDoubleStream(); |
17167 | 671 |
|
672 |
/** |
|
673 |
* Returns a {@code Stream} consisting of the elements of this stream, |
|
674 |
* each boxed to a {@code Long}. |
|
675 |
* |
|
19850 | 676 |
* <p>This is an <a href="package-summary.html#StreamOps">intermediate |
677 |
* operation</a>. |
|
678 |
* |
|
17167 | 679 |
* @return a {@code Stream} consistent of the elements of this stream, |
680 |
* each boxed to {@code Long} |
|
681 |
*/ |
|
682 |
Stream<Long> boxed(); |
|
683 |
||
684 |
@Override |
|
685 |
LongStream sequential(); |
|
686 |
||
687 |
@Override |
|
688 |
LongStream parallel(); |
|
689 |
||
690 |
@Override |
|
691 |
PrimitiveIterator.OfLong iterator(); |
|
692 |
||
693 |
@Override |
|
694 |
Spliterator.OfLong spliterator(); |
|
17195 | 695 |
|
696 |
// Static factories |
|
697 |
||
698 |
/** |
|
699 |
* Returns a builder for a {@code LongStream}. |
|
700 |
* |
|
701 |
* @return a stream builder |
|
702 |
*/ |
|
18825
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
703 |
public static Builder builder() { |
17195 | 704 |
return new Streams.LongStreamBuilderImpl(); |
705 |
} |
|
706 |
||
707 |
/** |
|
708 |
* Returns an empty sequential {@code LongStream}. |
|
709 |
* |
|
710 |
* @return an empty sequential stream |
|
711 |
*/ |
|
712 |
public static LongStream empty() { |
|
18822
4b6be7c19547
8019395: Consolidate StreamSupport.{stream,parallelStream} into a single method
psandoz
parents:
18820
diff
changeset
|
713 |
return StreamSupport.longStream(Spliterators.emptyLongSpliterator(), false); |
17195 | 714 |
} |
715 |
||
716 |
/** |
|
717 |
* Returns a sequential {@code LongStream} containing a single element. |
|
718 |
* |
|
719 |
* @param t the single element |
|
720 |
* @return a singleton sequential stream |
|
721 |
*/ |
|
722 |
public static LongStream of(long t) { |
|
18822
4b6be7c19547
8019395: Consolidate StreamSupport.{stream,parallelStream} into a single method
psandoz
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|
723 |
return StreamSupport.longStream(new Streams.LongStreamBuilderImpl(t), false); |
17195 | 724 |
} |
725 |
||
726 |
/** |
|
19850 | 727 |
* Returns a sequential ordered stream whose elements are the specified values. |
17195 | 728 |
* |
729 |
* @param values the elements of the new stream |
|
730 |
* @return the new stream |
|
731 |
*/ |
|
732 |
public static LongStream of(long... values) { |
|
733 |
return Arrays.stream(values); |
|
734 |
} |
|
735 |
||
736 |
/** |
|
19850 | 737 |
* Returns an infinite sequential ordered {@code LongStream} produced by iterative |
17195 | 738 |
* application of a function {@code f} to an initial element {@code seed}, |
739 |
* producing a {@code Stream} consisting of {@code seed}, {@code f(seed)}, |
|
740 |
* {@code f(f(seed))}, etc. |
|
741 |
* |
|
742 |
* <p>The first element (position {@code 0}) in the {@code LongStream} will |
|
743 |
* be the provided {@code seed}. For {@code n > 0}, the element at position |
|
744 |
* {@code n}, will be the result of applying the function {@code f} to the |
|
745 |
* element at position {@code n - 1}. |
|
746 |
* |
|
747 |
* @param seed the initial element |
|
25526 | 748 |
* @param f a function to be applied to the previous element to produce |
17195 | 749 |
* a new element |
750 |
* @return a new sequential {@code LongStream} |
|
751 |
*/ |
|
752 |
public static LongStream iterate(final long seed, final LongUnaryOperator f) { |
|
753 |
Objects.requireNonNull(f); |
|
754 |
final PrimitiveIterator.OfLong iterator = new PrimitiveIterator.OfLong() { |
|
755 |
long t = seed; |
|
756 |
||
757 |
@Override |
|
758 |
public boolean hasNext() { |
|
759 |
return true; |
|
760 |
} |
|
761 |
||
762 |
@Override |
|
763 |
public long nextLong() { |
|
764 |
long v = t; |
|
765 |
t = f.applyAsLong(t); |
|
766 |
return v; |
|
767 |
} |
|
768 |
}; |
|
769 |
return StreamSupport.longStream(Spliterators.spliteratorUnknownSize( |
|
770 |
iterator, |
|
18822
4b6be7c19547
8019395: Consolidate StreamSupport.{stream,parallelStream} into a single method
psandoz
parents:
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diff
changeset
|
771 |
Spliterator.ORDERED | Spliterator.IMMUTABLE | Spliterator.NONNULL), false); |
17195 | 772 |
} |
773 |
||
774 |
/** |
|
21339 | 775 |
* Returns an infinite sequential unordered stream where each element is |
776 |
* generated by the provided {@code LongSupplier}. This is suitable for |
|
777 |
* generating constant streams, streams of random elements, etc. |
|
17195 | 778 |
* |
779 |
* @param s the {@code LongSupplier} for generated elements |
|
21339 | 780 |
* @return a new infinite sequential unordered {@code LongStream} |
17195 | 781 |
*/ |
782 |
public static LongStream generate(LongSupplier s) { |
|
783 |
Objects.requireNonNull(s); |
|
18572
53b8b8c30086
8012987: Optimizations for Stream.limit/substream
psandoz
parents:
18158
diff
changeset
|
784 |
return StreamSupport.longStream( |
18822
4b6be7c19547
8019395: Consolidate StreamSupport.{stream,parallelStream} into a single method
psandoz
parents:
18820
diff
changeset
|
785 |
new StreamSpliterators.InfiniteSupplyingSpliterator.OfLong(Long.MAX_VALUE, s), false); |
17195 | 786 |
} |
787 |
||
788 |
/** |
|
19850 | 789 |
* Returns a sequential ordered {@code LongStream} from {@code startInclusive} |
17195 | 790 |
* (inclusive) to {@code endExclusive} (exclusive) by an incremental step of |
18158 | 791 |
* {@code 1}. |
17195 | 792 |
* |
18158 | 793 |
* @apiNote |
794 |
* <p>An equivalent sequence of increasing values can be produced |
|
795 |
* sequentially using a {@code for} loop as follows: |
|
17195 | 796 |
* <pre>{@code |
18158 | 797 |
* for (long i = startInclusive; i < endExclusive ; i++) { ... } |
17195 | 798 |
* }</pre> |
799 |
* |
|
800 |
* @param startInclusive the (inclusive) initial value |
|
801 |
* @param endExclusive the exclusive upper bound |
|
802 |
* @return a sequential {@code LongStream} for the range of {@code long} |
|
803 |
* elements |
|
804 |
*/ |
|
805 |
public static LongStream range(long startInclusive, final long endExclusive) { |
|
18158 | 806 |
if (startInclusive >= endExclusive) { |
807 |
return empty(); |
|
808 |
} else if (endExclusive - startInclusive < 0) { |
|
809 |
// Size of range > Long.MAX_VALUE |
|
810 |
// Split the range in two and concatenate |
|
811 |
// Note: if the range is [Long.MIN_VALUE, Long.MAX_VALUE) then |
|
812 |
// the lower range, [Long.MIN_VALUE, 0) will be further split in two |
|
18820 | 813 |
long m = startInclusive + Long.divideUnsigned(endExclusive - startInclusive, 2) + 1; |
814 |
return concat(range(startInclusive, m), range(m, endExclusive)); |
|
18158 | 815 |
} else { |
816 |
return StreamSupport.longStream( |
|
18822
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psandoz
parents:
18820
diff
changeset
|
817 |
new Streams.RangeLongSpliterator(startInclusive, endExclusive, false), false); |
18158 | 818 |
} |
17195 | 819 |
} |
820 |
||
821 |
/** |
|
19850 | 822 |
* Returns a sequential ordered {@code LongStream} from {@code startInclusive} |
18158 | 823 |
* (inclusive) to {@code endInclusive} (inclusive) by an incremental step of |
824 |
* {@code 1}. |
|
17195 | 825 |
* |
18158 | 826 |
* @apiNote |
17195 | 827 |
* <p>An equivalent sequence of increasing values can be produced |
828 |
* sequentially using a {@code for} loop as follows: |
|
829 |
* <pre>{@code |
|
18158 | 830 |
* for (long i = startInclusive; i <= endInclusive ; i++) { ... } |
17195 | 831 |
* }</pre> |
832 |
* |
|
833 |
* @param startInclusive the (inclusive) initial value |
|
18158 | 834 |
* @param endInclusive the inclusive upper bound |
17195 | 835 |
* @return a sequential {@code LongStream} for the range of {@code long} |
836 |
* elements |
|
837 |
*/ |
|
18158 | 838 |
public static LongStream rangeClosed(long startInclusive, final long endInclusive) { |
839 |
if (startInclusive > endInclusive) { |
|
17195 | 840 |
return empty(); |
18158 | 841 |
} else if (endInclusive - startInclusive + 1 <= 0) { |
842 |
// Size of range > Long.MAX_VALUE |
|
843 |
// Split the range in two and concatenate |
|
844 |
// Note: if the range is [Long.MIN_VALUE, Long.MAX_VALUE] then |
|
845 |
// the lower range, [Long.MIN_VALUE, 0), and upper range, |
|
846 |
// [0, Long.MAX_VALUE], will both be further split in two |
|
18820 | 847 |
long m = startInclusive + Long.divideUnsigned(endInclusive - startInclusive, 2) + 1; |
848 |
return concat(range(startInclusive, m), rangeClosed(m, endInclusive)); |
|
17195 | 849 |
} else { |
18158 | 850 |
return StreamSupport.longStream( |
18822
4b6be7c19547
8019395: Consolidate StreamSupport.{stream,parallelStream} into a single method
psandoz
parents:
18820
diff
changeset
|
851 |
new Streams.RangeLongSpliterator(startInclusive, endInclusive, true), false); |
17195 | 852 |
} |
853 |
} |
|
18820 | 854 |
|
855 |
/** |
|
19850 | 856 |
* Creates a lazily concatenated stream whose elements are all the |
857 |
* elements of the first stream followed by all the elements of the |
|
21339 | 858 |
* second stream. The resulting stream is ordered if both |
18820 | 859 |
* of the input streams are ordered, and parallel if either of the input |
19800 | 860 |
* streams is parallel. When the resulting stream is closed, the close |
861 |
* handlers for both input streams are invoked. |
|
18820 | 862 |
* |
21339 | 863 |
* @implNote |
864 |
* Use caution when constructing streams from repeated concatenation. |
|
865 |
* Accessing an element of a deeply concatenated stream can result in deep |
|
29103
1dbde34ad64c
8073779: StackOverflowError called StackOverflowException in javadoc
igerasim
parents:
25859
diff
changeset
|
866 |
* call chains, or even {@code StackOverflowError}. |
21339 | 867 |
* |
18820 | 868 |
* @param a the first stream |
19850 | 869 |
* @param b the second stream |
870 |
* @return the concatenation of the two input streams |
|
18820 | 871 |
*/ |
872 |
public static LongStream concat(LongStream a, LongStream b) { |
|
873 |
Objects.requireNonNull(a); |
|
874 |
Objects.requireNonNull(b); |
|
875 |
||
876 |
Spliterator.OfLong split = new Streams.ConcatSpliterator.OfLong( |
|
877 |
a.spliterator(), b.spliterator()); |
|
19800 | 878 |
LongStream stream = StreamSupport.longStream(split, a.isParallel() || b.isParallel()); |
879 |
return stream.onClose(Streams.composedClose(a, b)); |
|
18820 | 880 |
} |
18825
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
881 |
|
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
882 |
/** |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
883 |
* A mutable builder for a {@code LongStream}. |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
884 |
* |
19850 | 885 |
* <p>A stream builder has a lifecycle, which starts in a building |
886 |
* phase, during which elements can be added, and then transitions to a built |
|
887 |
* phase, after which elements may not be added. The built phase begins |
|
18825
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
888 |
* begins when the {@link #build()} method is called, which creates an |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
889 |
* ordered stream whose elements are the elements that were added to the |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
890 |
* stream builder, in the order they were added. |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
891 |
* |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
892 |
* @see LongStream#builder() |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
893 |
* @since 1.8 |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
894 |
*/ |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
895 |
public interface Builder extends LongConsumer { |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
896 |
|
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
897 |
/** |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
898 |
* Adds an element to the stream being built. |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
899 |
* |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
900 |
* @throws IllegalStateException if the builder has already transitioned |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
901 |
* to the built state |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
902 |
*/ |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
903 |
@Override |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
904 |
void accept(long t); |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
905 |
|
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
906 |
/** |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
907 |
* Adds an element to the stream being built. |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
908 |
* |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
909 |
* @implSpec |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
910 |
* The default implementation behaves as if: |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
911 |
* <pre>{@code |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
912 |
* accept(t) |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
913 |
* return this; |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
914 |
* }</pre> |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
915 |
* |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
916 |
* @param t the element to add |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
917 |
* @return {@code this} builder |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
918 |
* @throws IllegalStateException if the builder has already transitioned |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
919 |
* to the built state |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
920 |
*/ |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
921 |
default Builder add(long t) { |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
922 |
accept(t); |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
923 |
return this; |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
924 |
} |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
925 |
|
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
926 |
/** |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
927 |
* Builds the stream, transitioning this builder to the built state. |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
928 |
* An {@code IllegalStateException} is thrown if there are further |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
929 |
* attempts to operate on the builder after it has entered the built |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
930 |
* state. |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
931 |
* |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
932 |
* @return the built stream |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
933 |
* @throws IllegalStateException if the builder has already transitioned |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
934 |
* to the built state |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
935 |
*/ |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
936 |
LongStream build(); |
06636235cd12
8020062: Nest StreamBuilder interfaces inside relevant Stream interfaces
henryjen
parents:
18822
diff
changeset
|
937 |
} |
17167 | 938 |
} |