| /* |
| * Copyright (c) 2013, 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| package java.util.stream; |
| |
| import java.util.LongSummaryStatistics; |
| import java.util.Objects; |
| import java.util.OptionalDouble; |
| import java.util.OptionalLong; |
| import java.util.PrimitiveIterator; |
| import java.util.Spliterator; |
| import java.util.Spliterators; |
| import java.util.function.BiConsumer; |
| import java.util.function.BinaryOperator; |
| import java.util.function.IntFunction; |
| import java.util.function.LongBinaryOperator; |
| import java.util.function.LongConsumer; |
| import java.util.function.LongFunction; |
| import java.util.function.LongPredicate; |
| import java.util.function.LongToDoubleFunction; |
| import java.util.function.LongToIntFunction; |
| import java.util.function.LongUnaryOperator; |
| import java.util.function.ObjLongConsumer; |
| import java.util.function.Supplier; |
| |
| /** |
| * Abstract base class for an intermediate pipeline stage or pipeline source |
| * stage implementing whose elements are of type {@code long}. |
| * |
| * @param <E_IN> type of elements in the upstream source |
| * @since 1.8 |
| */ |
| abstract class LongPipeline<E_IN> |
| extends AbstractPipeline<E_IN, Long, LongStream> |
| implements LongStream { |
| |
| /** |
| * Constructor for the head of a stream pipeline. |
| * |
| * @param source {@code Supplier<Spliterator>} describing the stream source |
| * @param sourceFlags the source flags for the stream source, described in |
| * {@link StreamOpFlag} |
| * @param parallel {@code true} if the pipeline is parallel |
| */ |
| LongPipeline(Supplier<? extends Spliterator<Long>> source, |
| int sourceFlags, boolean parallel) { |
| super(source, sourceFlags, parallel); |
| } |
| |
| /** |
| * Constructor for the head of a stream pipeline. |
| * |
| * @param source {@code Spliterator} describing the stream source |
| * @param sourceFlags the source flags for the stream source, described in |
| * {@link StreamOpFlag} |
| * @param parallel {@code true} if the pipeline is parallel |
| */ |
| LongPipeline(Spliterator<Long> source, |
| int sourceFlags, boolean parallel) { |
| super(source, sourceFlags, parallel); |
| } |
| |
| /** |
| * Constructor for appending an intermediate operation onto an existing pipeline. |
| * |
| * @param upstream the upstream element source. |
| * @param opFlags the operation flags |
| */ |
| LongPipeline(AbstractPipeline<?, E_IN, ?> upstream, int opFlags) { |
| super(upstream, opFlags); |
| } |
| |
| /** |
| * Adapt a {@code Sink<Long> to an {@code LongConsumer}, ideally simply |
| * by casting. |
| */ |
| private static LongConsumer adapt(Sink<Long> sink) { |
| if (sink instanceof LongConsumer) { |
| return (LongConsumer) sink; |
| } else { |
| if (Tripwire.ENABLED) |
| Tripwire.trip(AbstractPipeline.class, |
| "using LongStream.adapt(Sink<Long> s)"); |
| return sink::accept; |
| } |
| } |
| |
| /** |
| * Adapt a {@code Spliterator<Long>} to a {@code Spliterator.OfLong}. |
| * |
| * @implNote |
| * The implementation attempts to cast to a Spliterator.OfLong, and throws |
| * an exception if this cast is not possible. |
| */ |
| private static Spliterator.OfLong adapt(Spliterator<Long> s) { |
| if (s instanceof Spliterator.OfLong) { |
| return (Spliterator.OfLong) s; |
| } else { |
| if (Tripwire.ENABLED) |
| Tripwire.trip(AbstractPipeline.class, |
| "using LongStream.adapt(Spliterator<Long> s)"); |
| throw new UnsupportedOperationException("LongStream.adapt(Spliterator<Long> s)"); |
| } |
| } |
| |
| |
| // Shape-specific methods |
| |
| @Override |
| final StreamShape getOutputShape() { |
| return StreamShape.LONG_VALUE; |
| } |
| |
| @Override |
| final <P_IN> Node<Long> evaluateToNode(PipelineHelper<Long> helper, |
| Spliterator<P_IN> spliterator, |
| boolean flattenTree, |
| IntFunction<Long[]> generator) { |
| return Nodes.collectLong(helper, spliterator, flattenTree); |
| } |
| |
| @Override |
| final <P_IN> Spliterator<Long> wrap(PipelineHelper<Long> ph, |
| Supplier<Spliterator<P_IN>> supplier, |
| boolean isParallel) { |
| return new StreamSpliterators.LongWrappingSpliterator<>(ph, supplier, isParallel); |
| } |
| |
| @Override |
| @SuppressWarnings("unchecked") |
| final Spliterator.OfLong lazySpliterator(Supplier<? extends Spliterator<Long>> supplier) { |
| return new StreamSpliterators.DelegatingSpliterator.OfLong((Supplier<Spliterator.OfLong>) supplier); |
| } |
| |
| @Override |
| final boolean forEachWithCancel(Spliterator<Long> spliterator, Sink<Long> sink) { |
| Spliterator.OfLong spl = adapt(spliterator); |
| LongConsumer adaptedSink = adapt(sink); |
| boolean cancelled; |
| do { } while (!(cancelled = sink.cancellationRequested()) && spl.tryAdvance(adaptedSink)); |
| return cancelled; |
| } |
| |
| @Override |
| final Node.Builder<Long> makeNodeBuilder(long exactSizeIfKnown, IntFunction<Long[]> generator) { |
| return Nodes.longBuilder(exactSizeIfKnown); |
| } |
| |
| private <U> Stream<U> mapToObj(LongFunction<? extends U> mapper, int opFlags) { |
| return new ReferencePipeline.StatelessOp<Long, U>(this, StreamShape.LONG_VALUE, opFlags) { |
| @Override |
| Sink<Long> opWrapSink(int flags, Sink<U> sink) { |
| return new Sink.ChainedLong<U>(sink) { |
| @Override |
| public void accept(long t) { |
| downstream.accept(mapper.apply(t)); |
| } |
| }; |
| } |
| }; |
| } |
| |
| // LongStream |
| |
| @Override |
| public final PrimitiveIterator.OfLong iterator() { |
| return Spliterators.iterator(spliterator()); |
| } |
| |
| @Override |
| public final Spliterator.OfLong spliterator() { |
| return adapt(super.spliterator()); |
| } |
| |
| // Stateless intermediate ops from LongStream |
| |
| @Override |
| public final DoubleStream asDoubleStream() { |
| return new DoublePipeline.StatelessOp<Long>(this, StreamShape.LONG_VALUE, StreamOpFlag.NOT_DISTINCT) { |
| @Override |
| Sink<Long> opWrapSink(int flags, Sink<Double> sink) { |
| return new Sink.ChainedLong<Double>(sink) { |
| @Override |
| public void accept(long t) { |
| downstream.accept((double) t); |
| } |
| }; |
| } |
| }; |
| } |
| |
| @Override |
| public final Stream<Long> boxed() { |
| return mapToObj(Long::valueOf, 0); |
| } |
| |
| @Override |
| public final LongStream map(LongUnaryOperator mapper) { |
| Objects.requireNonNull(mapper); |
| return new StatelessOp<Long>(this, StreamShape.LONG_VALUE, |
| StreamOpFlag.NOT_SORTED | StreamOpFlag.NOT_DISTINCT) { |
| @Override |
| Sink<Long> opWrapSink(int flags, Sink<Long> sink) { |
| return new Sink.ChainedLong<Long>(sink) { |
| @Override |
| public void accept(long t) { |
| downstream.accept(mapper.applyAsLong(t)); |
| } |
| }; |
| } |
| }; |
| } |
| |
| @Override |
| public final <U> Stream<U> mapToObj(LongFunction<? extends U> mapper) { |
| Objects.requireNonNull(mapper); |
| return mapToObj(mapper, StreamOpFlag.NOT_SORTED | StreamOpFlag.NOT_DISTINCT); |
| } |
| |
| @Override |
| public final IntStream mapToInt(LongToIntFunction mapper) { |
| Objects.requireNonNull(mapper); |
| return new IntPipeline.StatelessOp<Long>(this, StreamShape.LONG_VALUE, |
| StreamOpFlag.NOT_SORTED | StreamOpFlag.NOT_DISTINCT) { |
| @Override |
| Sink<Long> opWrapSink(int flags, Sink<Integer> sink) { |
| return new Sink.ChainedLong<Integer>(sink) { |
| @Override |
| public void accept(long t) { |
| downstream.accept(mapper.applyAsInt(t)); |
| } |
| }; |
| } |
| }; |
| } |
| |
| @Override |
| public final DoubleStream mapToDouble(LongToDoubleFunction mapper) { |
| Objects.requireNonNull(mapper); |
| return new DoublePipeline.StatelessOp<Long>(this, StreamShape.LONG_VALUE, |
| StreamOpFlag.NOT_SORTED | StreamOpFlag.NOT_DISTINCT) { |
| @Override |
| Sink<Long> opWrapSink(int flags, Sink<Double> sink) { |
| return new Sink.ChainedLong<Double>(sink) { |
| @Override |
| public void accept(long t) { |
| downstream.accept(mapper.applyAsDouble(t)); |
| } |
| }; |
| } |
| }; |
| } |
| |
| @Override |
| public final LongStream flatMap(LongFunction<? extends LongStream> mapper) { |
| Objects.requireNonNull(mapper); |
| return new StatelessOp<Long>(this, StreamShape.LONG_VALUE, |
| StreamOpFlag.NOT_SORTED | StreamOpFlag.NOT_DISTINCT | StreamOpFlag.NOT_SIZED) { |
| @Override |
| Sink<Long> opWrapSink(int flags, Sink<Long> sink) { |
| return new Sink.ChainedLong<Long>(sink) { |
| @Override |
| public void begin(long size) { |
| downstream.begin(-1); |
| } |
| |
| @Override |
| public void accept(long t) { |
| try (LongStream result = mapper.apply(t)) { |
| // We can do better that this too; optimize for depth=0 case and just grab spliterator and forEach it |
| if (result != null) |
| result.sequential().forEach(i -> downstream.accept(i)); |
| } |
| } |
| }; |
| } |
| }; |
| } |
| |
| @Override |
| public LongStream unordered() { |
| if (!isOrdered()) |
| return this; |
| return new StatelessOp<Long>(this, StreamShape.LONG_VALUE, StreamOpFlag.NOT_ORDERED) { |
| @Override |
| Sink<Long> opWrapSink(int flags, Sink<Long> sink) { |
| return sink; |
| } |
| }; |
| } |
| |
| @Override |
| public final LongStream filter(LongPredicate predicate) { |
| Objects.requireNonNull(predicate); |
| return new StatelessOp<Long>(this, StreamShape.LONG_VALUE, |
| StreamOpFlag.NOT_SIZED) { |
| @Override |
| Sink<Long> opWrapSink(int flags, Sink<Long> sink) { |
| return new Sink.ChainedLong<Long>(sink) { |
| @Override |
| public void begin(long size) { |
| downstream.begin(-1); |
| } |
| |
| @Override |
| public void accept(long t) { |
| if (predicate.test(t)) |
| downstream.accept(t); |
| } |
| }; |
| } |
| }; |
| } |
| |
| @Override |
| public final LongStream peek(LongConsumer action) { |
| Objects.requireNonNull(action); |
| return new StatelessOp<Long>(this, StreamShape.LONG_VALUE, |
| 0) { |
| @Override |
| Sink<Long> opWrapSink(int flags, Sink<Long> sink) { |
| return new Sink.ChainedLong<Long>(sink) { |
| @Override |
| public void accept(long t) { |
| action.accept(t); |
| downstream.accept(t); |
| } |
| }; |
| } |
| }; |
| } |
| |
| // Stateful intermediate ops from LongStream |
| |
| @Override |
| public final LongStream limit(long maxSize) { |
| if (maxSize < 0) |
| throw new IllegalArgumentException(Long.toString(maxSize)); |
| return SliceOps.makeLong(this, 0, maxSize); |
| } |
| |
| @Override |
| public final LongStream skip(long n) { |
| if (n < 0) |
| throw new IllegalArgumentException(Long.toString(n)); |
| if (n == 0) |
| return this; |
| else |
| return SliceOps.makeLong(this, n, -1); |
| } |
| |
| @Override |
| public final LongStream takeWhile(LongPredicate predicate) { |
| return WhileOps.makeTakeWhileLong(this, predicate); |
| } |
| |
| @Override |
| public final LongStream dropWhile(LongPredicate predicate) { |
| return WhileOps.makeDropWhileLong(this, predicate); |
| } |
| |
| @Override |
| public final LongStream sorted() { |
| return SortedOps.makeLong(this); |
| } |
| |
| @Override |
| public final LongStream distinct() { |
| // While functional and quick to implement, this approach is not very efficient. |
| // An efficient version requires a long-specific map/set implementation. |
| return boxed().distinct().mapToLong(i -> (long) i); |
| } |
| |
| // Terminal ops from LongStream |
| |
| @Override |
| public void forEach(LongConsumer action) { |
| evaluate(ForEachOps.makeLong(action, false)); |
| } |
| |
| @Override |
| public void forEachOrdered(LongConsumer action) { |
| evaluate(ForEachOps.makeLong(action, true)); |
| } |
| |
| @Override |
| public final long sum() { |
| // use better algorithm to compensate for intermediate overflow? |
| return reduce(0, Long::sum); |
| } |
| |
| @Override |
| public final OptionalLong min() { |
| return reduce(Math::min); |
| } |
| |
| @Override |
| public final OptionalLong max() { |
| return reduce(Math::max); |
| } |
| |
| @Override |
| public final OptionalDouble average() { |
| long[] avg = collect(() -> new long[2], |
| (ll, i) -> { |
| ll[0]++; |
| ll[1] += i; |
| }, |
| (ll, rr) -> { |
| ll[0] += rr[0]; |
| ll[1] += rr[1]; |
| }); |
| return avg[0] > 0 |
| ? OptionalDouble.of((double) avg[1] / avg[0]) |
| : OptionalDouble.empty(); |
| } |
| |
| @Override |
| public final long count() { |
| return evaluate(ReduceOps.makeLongCounting()); |
| } |
| |
| @Override |
| public final LongSummaryStatistics summaryStatistics() { |
| return collect(LongSummaryStatistics::new, LongSummaryStatistics::accept, |
| LongSummaryStatistics::combine); |
| } |
| |
| @Override |
| public final long reduce(long identity, LongBinaryOperator op) { |
| return evaluate(ReduceOps.makeLong(identity, op)); |
| } |
| |
| @Override |
| public final OptionalLong reduce(LongBinaryOperator op) { |
| return evaluate(ReduceOps.makeLong(op)); |
| } |
| |
| @Override |
| public final <R> R collect(Supplier<R> supplier, |
| ObjLongConsumer<R> accumulator, |
| BiConsumer<R, R> combiner) { |
| Objects.requireNonNull(combiner); |
| BinaryOperator<R> operator = (left, right) -> { |
| combiner.accept(left, right); |
| return left; |
| }; |
| return evaluate(ReduceOps.makeLong(supplier, accumulator, operator)); |
| } |
| |
| @Override |
| public final boolean anyMatch(LongPredicate predicate) { |
| return evaluate(MatchOps.makeLong(predicate, MatchOps.MatchKind.ANY)); |
| } |
| |
| @Override |
| public final boolean allMatch(LongPredicate predicate) { |
| return evaluate(MatchOps.makeLong(predicate, MatchOps.MatchKind.ALL)); |
| } |
| |
| @Override |
| public final boolean noneMatch(LongPredicate predicate) { |
| return evaluate(MatchOps.makeLong(predicate, MatchOps.MatchKind.NONE)); |
| } |
| |
| @Override |
| public final OptionalLong findFirst() { |
| return evaluate(FindOps.makeLong(true)); |
| } |
| |
| @Override |
| public final OptionalLong findAny() { |
| return evaluate(FindOps.makeLong(false)); |
| } |
| |
| @Override |
| public final long[] toArray() { |
| return Nodes.flattenLong((Node.OfLong) evaluateToArrayNode(Long[]::new)) |
| .asPrimitiveArray(); |
| } |
| |
| |
| // |
| |
| /** |
| * Source stage of a LongPipeline. |
| * |
| * @param <E_IN> type of elements in the upstream source |
| * @since 1.8 |
| */ |
| static class Head<E_IN> extends LongPipeline<E_IN> { |
| /** |
| * Constructor for the source stage of a LongStream. |
| * |
| * @param source {@code Supplier<Spliterator>} describing the stream |
| * source |
| * @param sourceFlags the source flags for the stream source, described |
| * in {@link StreamOpFlag} |
| * @param parallel {@code true} if the pipeline is parallel |
| */ |
| Head(Supplier<? extends Spliterator<Long>> source, |
| int sourceFlags, boolean parallel) { |
| super(source, sourceFlags, parallel); |
| } |
| |
| /** |
| * Constructor for the source stage of a LongStream. |
| * |
| * @param source {@code Spliterator} describing the stream source |
| * @param sourceFlags the source flags for the stream source, described |
| * in {@link StreamOpFlag} |
| * @param parallel {@code true} if the pipeline is parallel |
| */ |
| Head(Spliterator<Long> source, |
| int sourceFlags, boolean parallel) { |
| super(source, sourceFlags, parallel); |
| } |
| |
| @Override |
| final boolean opIsStateful() { |
| throw new UnsupportedOperationException(); |
| } |
| |
| @Override |
| final Sink<E_IN> opWrapSink(int flags, Sink<Long> sink) { |
| throw new UnsupportedOperationException(); |
| } |
| |
| // Optimized sequential terminal operations for the head of the pipeline |
| |
| @Override |
| public void forEach(LongConsumer action) { |
| if (!isParallel()) { |
| adapt(sourceStageSpliterator()).forEachRemaining(action); |
| } else { |
| super.forEach(action); |
| } |
| } |
| |
| @Override |
| public void forEachOrdered(LongConsumer action) { |
| if (!isParallel()) { |
| adapt(sourceStageSpliterator()).forEachRemaining(action); |
| } else { |
| super.forEachOrdered(action); |
| } |
| } |
| } |
| |
| /** Base class for a stateless intermediate stage of a LongStream. |
| * |
| * @param <E_IN> type of elements in the upstream source |
| * @since 1.8 |
| */ |
| abstract static class StatelessOp<E_IN> extends LongPipeline<E_IN> { |
| /** |
| * Construct a new LongStream by appending a stateless intermediate |
| * operation to an existing stream. |
| * @param upstream The upstream pipeline stage |
| * @param inputShape The stream shape for the upstream pipeline stage |
| * @param opFlags Operation flags for the new stage |
| */ |
| StatelessOp(AbstractPipeline<?, E_IN, ?> upstream, |
| StreamShape inputShape, |
| int opFlags) { |
| super(upstream, opFlags); |
| assert upstream.getOutputShape() == inputShape; |
| } |
| |
| @Override |
| final boolean opIsStateful() { |
| return false; |
| } |
| } |
| |
| /** |
| * Base class for a stateful intermediate stage of a LongStream. |
| * |
| * @param <E_IN> type of elements in the upstream source |
| * @since 1.8 |
| */ |
| abstract static class StatefulOp<E_IN> extends LongPipeline<E_IN> { |
| /** |
| * Construct a new LongStream by appending a stateful intermediate |
| * operation to an existing stream. |
| * @param upstream The upstream pipeline stage |
| * @param inputShape The stream shape for the upstream pipeline stage |
| * @param opFlags Operation flags for the new stage |
| */ |
| StatefulOp(AbstractPipeline<?, E_IN, ?> upstream, |
| StreamShape inputShape, |
| int opFlags) { |
| super(upstream, opFlags); |
| assert upstream.getOutputShape() == inputShape; |
| } |
| |
| @Override |
| final boolean opIsStateful() { |
| return true; |
| } |
| |
| @Override |
| abstract <P_IN> Node<Long> opEvaluateParallel(PipelineHelper<Long> helper, |
| Spliterator<P_IN> spliterator, |
| IntFunction<Long[]> generator); |
| } |
| } |