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/*
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* Copyright (c) 2012, 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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import java.util.Objects;
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import java.util.Optional;
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import java.util.OptionalDouble;
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import java.util.OptionalInt;
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import java.util.OptionalLong;
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import java.util.Spliterator;
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import java.util.concurrent.CountedCompleter;
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import java.util.function.BiConsumer;
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import java.util.function.BiFunction;
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import java.util.function.BinaryOperator;
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import java.util.function.DoubleBinaryOperator;
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import java.util.function.IntBinaryOperator;
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import java.util.function.LongBinaryOperator;
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import java.util.function.ObjDoubleConsumer;
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import java.util.function.ObjIntConsumer;
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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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* Factory for the creating instances of {@code TerminalOp) that implement
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* reductions.
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*
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* @since 1.8
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*/
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final class ReduceOps {
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private ReduceOps() { }
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/**
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* Constructs a {@code TerminalOp} that implements a functional reduce on
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* reference values.
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*
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* @param <T> the type of the input elements
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* @param <U> the type of the result
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* @param seed the identity element for the reduction
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* @param reducer the accumulating function that incorporates an additional
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* input element into the result
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* @param combiner the combining function that combines two intermediate
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* results
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* @return a {@code TerminalOp} implementing the reduction
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*/
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public static <T, U> TerminalOp<T, U>
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makeRef(U seed, BiFunction<U, ? super T, U> reducer, BinaryOperator<U> combiner) {
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Objects.requireNonNull(reducer);
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Objects.requireNonNull(combiner);
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class ReducingSink extends Box<U> implements AccumulatingSink<T, U, ReducingSink> {
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@Override
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public void begin(long size) {
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state = seed;
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}
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@Override
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public void accept(T t) {
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state = reducer.apply(state, t);
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}
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@Override
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public void combine(ReducingSink other) {
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state = combiner.apply(state, other.state);
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}
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}
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return new ReduceOp<T, U, ReducingSink>(StreamShape.REFERENCE) {
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@Override
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public ReducingSink makeSink() {
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return new ReducingSink();
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}
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};
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}
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/**
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* Constructs a {@code TerminalOp} that implements a functional reduce on
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* reference values producing an optional reference result.
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*
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* @param <T> The type of the input elements, and the type of the result
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* @param operator The reducing function
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* @return A {@code TerminalOp} implementing the reduction
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*/
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public static <T> TerminalOp<T, Optional<T>>
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makeRef(BinaryOperator<T> operator) {
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Objects.requireNonNull(operator);
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class ReducingSink
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implements AccumulatingSink<T, Optional<T>, ReducingSink> {
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private boolean empty;
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private T state;
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public void begin(long size) {
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empty = true;
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state = null;
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}
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@Override
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public void accept(T t) {
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if (empty) {
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empty = false;
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state = t;
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} else {
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state = operator.apply(state, t);
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}
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}
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@Override
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public Optional<T> get() {
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return empty ? Optional.empty() : Optional.of(state);
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}
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@Override
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public void combine(ReducingSink other) {
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if (!other.empty)
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accept(other.state);
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}
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}
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return new ReduceOp<T, Optional<T>, ReducingSink>(StreamShape.REFERENCE) {
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@Override
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public ReducingSink makeSink() {
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return new ReducingSink();
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}
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};
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}
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/**
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* Constructs a {@code TerminalOp} that implements a mutable reduce on
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* reference values.
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*
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* @param <T> the type of the input elements
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* @param <R> the type of the result
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* @param collector a {@code Collector} defining the reduction
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* @return a {@code ReduceOp} implementing the reduction
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*/
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public static <T,R> TerminalOp<T, R>
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makeRef(Collector<? super T,R> collector) {
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Supplier<R> supplier = Objects.requireNonNull(collector).resultSupplier();
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BiFunction<R, ? super T, R> accumulator = collector.accumulator();
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BinaryOperator<R> combiner = collector.combiner();
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class ReducingSink extends Box<R>
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implements AccumulatingSink<T, R, ReducingSink> {
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@Override
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public void begin(long size) {
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state = supplier.get();
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}
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@Override
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public void accept(T t) {
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R newResult = accumulator.apply(state, t);
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if (state != newResult)
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state = newResult;
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}
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@Override
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public void combine(ReducingSink other) {
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state = combiner.apply(state, other.state);
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}
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}
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return new ReduceOp<T, R, ReducingSink>(StreamShape.REFERENCE) {
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@Override
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public ReducingSink makeSink() {
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return new ReducingSink();
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}
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@Override
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public int getOpFlags() {
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return collector.characteristics().contains(Collector.Characteristics.UNORDERED)
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? StreamOpFlag.NOT_ORDERED
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: 0;
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}
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};
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}
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/**
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* Constructs a {@code TerminalOp} that implements a mutable reduce on
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* reference values.
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*
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* @param <T> the type of the input elements
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* @param <R> the type of the result
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* @param seedFactory a factory to produce a new base accumulator
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* @param accumulator a function to incorporate an element into an
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* accumulator
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* @param reducer a function to combine an accumulator into another
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* @return a {@code TerminalOp} implementing the reduction
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*/
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public static <T, R> TerminalOp<T, R>
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makeRef(Supplier<R> seedFactory,
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BiConsumer<R, ? super T> accumulator,
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BiConsumer<R,R> reducer) {
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Objects.requireNonNull(seedFactory);
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Objects.requireNonNull(accumulator);
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Objects.requireNonNull(reducer);
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class ReducingSink extends Box<R>
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implements AccumulatingSink<T, R, ReducingSink> {
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@Override
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public void begin(long size) {
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state = seedFactory.get();
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}
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@Override
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public void accept(T t) {
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accumulator.accept(state, t);
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}
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@Override
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public void combine(ReducingSink other) {
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reducer.accept(state, other.state);
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}
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}
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return new ReduceOp<T, R, ReducingSink>(StreamShape.REFERENCE) {
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@Override
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public ReducingSink makeSink() {
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return new ReducingSink();
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}
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};
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}
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/**
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* Constructs a {@code TerminalOp} that implements a functional reduce on
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* {@code int} values.
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*
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* @param identity the identity for the combining function
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* @param operator the combining function
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* @return a {@code TerminalOp} implementing the reduction
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*/
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public static TerminalOp<Integer, Integer>
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makeInt(int identity, IntBinaryOperator operator) {
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Objects.requireNonNull(operator);
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class ReducingSink
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implements AccumulatingSink<Integer, Integer, ReducingSink>, Sink.OfInt {
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private int state;
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@Override
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public void begin(long size) {
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state = identity;
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}
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@Override
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public void accept(int t) {
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state = operator.applyAsInt(state, t);
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}
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@Override
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public Integer get() {
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return state;
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}
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@Override
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public void combine(ReducingSink other) {
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accept(other.state);
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}
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}
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return new ReduceOp<Integer, Integer, ReducingSink>(StreamShape.INT_VALUE) {
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@Override
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public ReducingSink makeSink() {
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return new ReducingSink();
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}
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};
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}
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/**
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* Constructs a {@code TerminalOp} that implements a functional reduce on
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* {@code int} values, producing an optional integer result.
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*
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* @param operator the combining function
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* @return a {@code TerminalOp} implementing the reduction
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*/
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public static TerminalOp<Integer, OptionalInt>
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makeInt(IntBinaryOperator operator) {
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Objects.requireNonNull(operator);
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class ReducingSink
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implements AccumulatingSink<Integer, OptionalInt, ReducingSink>, Sink.OfInt {
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private boolean empty;
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private int state;
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public void begin(long size) {
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empty = true;
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state = 0;
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}
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@Override
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public void accept(int t) {
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if (empty) {
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empty = false;
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state = t;
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}
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else {
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state = operator.applyAsInt(state, t);
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}
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}
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@Override
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public OptionalInt get() {
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return empty ? OptionalInt.empty() : OptionalInt.of(state);
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}
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@Override
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public void combine(ReducingSink other) {
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if (!other.empty)
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accept(other.state);
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}
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}
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return new ReduceOp<Integer, OptionalInt, ReducingSink>(StreamShape.INT_VALUE) {
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@Override
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public ReducingSink makeSink() {
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return new ReducingSink();
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}
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};
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}
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/**
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* Constructs a {@code TerminalOp} that implements a mutable reduce on
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* {@code int} values.
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*
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* @param <R> The type of the result
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* @param supplier a factory to produce a new accumulator of the result type
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* @param accumulator a function to incorporate an int into an
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* accumulator
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* @param combiner a function to combine an accumulator into another
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* @return A {@code ReduceOp} implementing the reduction
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*/
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public static <R> TerminalOp<Integer, R>
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makeInt(Supplier<R> supplier,
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ObjIntConsumer<R> accumulator,
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BinaryOperator<R> combiner) {
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Objects.requireNonNull(supplier);
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Objects.requireNonNull(accumulator);
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Objects.requireNonNull(combiner);
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class ReducingSink extends Box<R>
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implements AccumulatingSink<Integer, R, ReducingSink>, Sink.OfInt {
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@Override
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public void begin(long size) {
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state = supplier.get();
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}
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@Override
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public void accept(int t) {
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accumulator.accept(state, t);
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}
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@Override
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public void combine(ReducingSink other) {
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state = combiner.apply(state, other.state);
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}
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}
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return new ReduceOp<Integer, R, ReducingSink>(StreamShape.INT_VALUE) {
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@Override
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public ReducingSink makeSink() {
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return new ReducingSink();
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}
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};
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}
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/**
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* Constructs a {@code TerminalOp} that implements a functional reduce on
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* {@code long} values.
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*
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* @param identity the identity for the combining function
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* @param operator the combining function
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* @return a {@code TerminalOp} implementing the reduction
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*/
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public static TerminalOp<Long, Long>
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makeLong(long identity, LongBinaryOperator operator) {
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Objects.requireNonNull(operator);
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class ReducingSink
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implements AccumulatingSink<Long, Long, ReducingSink>, Sink.OfLong {
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private long state;
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@Override
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public void begin(long size) {
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state = identity;
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}
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@Override
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public void accept(long t) {
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state = operator.applyAsLong(state, t);
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}
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@Override
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public Long get() {
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return state;
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}
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@Override
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public void combine(ReducingSink other) {
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accept(other.state);
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}
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}
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return new ReduceOp<Long, Long, ReducingSink>(StreamShape.LONG_VALUE) {
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@Override
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public ReducingSink makeSink() {
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return new ReducingSink();
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}
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};
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}
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/**
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* Constructs a {@code TerminalOp} that implements a functional reduce on
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* {@code long} values, producing an optional long result.
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*
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* @param operator the combining function
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* @return a {@code TerminalOp} implementing the reduction
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*/
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public static TerminalOp<Long, OptionalLong>
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makeLong(LongBinaryOperator operator) {
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Objects.requireNonNull(operator);
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class ReducingSink
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implements AccumulatingSink<Long, OptionalLong, ReducingSink>, Sink.OfLong {
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private boolean empty;
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private long state;
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public void begin(long size) {
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empty = true;
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state = 0;
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}
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@Override
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public void accept(long t) {
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if (empty) {
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empty = false;
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state = t;
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}
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else {
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state = operator.applyAsLong(state, t);
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}
|
|
446 |
}
|
|
447 |
|
|
448 |
@Override
|
|
449 |
public OptionalLong get() {
|
|
450 |
return empty ? OptionalLong.empty() : OptionalLong.of(state);
|
|
451 |
}
|
|
452 |
|
|
453 |
@Override
|
|
454 |
public void combine(ReducingSink other) {
|
|
455 |
if (!other.empty)
|
|
456 |
accept(other.state);
|
|
457 |
}
|
|
458 |
}
|
|
459 |
return new ReduceOp<Long, OptionalLong, ReducingSink>(StreamShape.LONG_VALUE) {
|
|
460 |
@Override
|
|
461 |
public ReducingSink makeSink() {
|
|
462 |
return new ReducingSink();
|
|
463 |
}
|
|
464 |
};
|
|
465 |
}
|
|
466 |
|
|
467 |
/**
|
|
468 |
* Constructs a {@code TerminalOp} that implements a mutable reduce on
|
|
469 |
* {@code long} values.
|
|
470 |
*
|
|
471 |
* @param <R> the type of the result
|
|
472 |
* @param supplier a factory to produce a new accumulator of the result type
|
|
473 |
* @param accumulator a function to incorporate an int into an
|
|
474 |
* accumulator
|
|
475 |
* @param combiner a function to combine an accumulator into another
|
|
476 |
* @return a {@code TerminalOp} implementing the reduction
|
|
477 |
*/
|
|
478 |
public static <R> TerminalOp<Long, R>
|
|
479 |
makeLong(Supplier<R> supplier,
|
|
480 |
ObjLongConsumer<R> accumulator,
|
|
481 |
BinaryOperator<R> combiner) {
|
|
482 |
Objects.requireNonNull(supplier);
|
|
483 |
Objects.requireNonNull(accumulator);
|
|
484 |
Objects.requireNonNull(combiner);
|
|
485 |
class ReducingSink extends Box<R>
|
|
486 |
implements AccumulatingSink<Long, R, ReducingSink>, Sink.OfLong {
|
|
487 |
@Override
|
|
488 |
public void begin(long size) {
|
|
489 |
state = supplier.get();
|
|
490 |
}
|
|
491 |
|
|
492 |
@Override
|
|
493 |
public void accept(long t) {
|
|
494 |
accumulator.accept(state, t);
|
|
495 |
}
|
|
496 |
|
|
497 |
@Override
|
|
498 |
public void combine(ReducingSink other) {
|
|
499 |
state = combiner.apply(state, other.state);
|
|
500 |
}
|
|
501 |
}
|
|
502 |
return new ReduceOp<Long, R, ReducingSink>(StreamShape.LONG_VALUE) {
|
|
503 |
@Override
|
|
504 |
public ReducingSink makeSink() {
|
|
505 |
return new ReducingSink();
|
|
506 |
}
|
|
507 |
};
|
|
508 |
}
|
|
509 |
|
|
510 |
/**
|
|
511 |
* Constructs a {@code TerminalOp} that implements a functional reduce on
|
|
512 |
* {@code double} values.
|
|
513 |
*
|
|
514 |
* @param identity the identity for the combining function
|
|
515 |
* @param operator the combining function
|
|
516 |
* @return a {@code TerminalOp} implementing the reduction
|
|
517 |
*/
|
|
518 |
public static TerminalOp<Double, Double>
|
|
519 |
makeDouble(double identity, DoubleBinaryOperator operator) {
|
|
520 |
Objects.requireNonNull(operator);
|
|
521 |
class ReducingSink
|
|
522 |
implements AccumulatingSink<Double, Double, ReducingSink>, Sink.OfDouble {
|
|
523 |
private double state;
|
|
524 |
|
|
525 |
@Override
|
|
526 |
public void begin(long size) {
|
|
527 |
state = identity;
|
|
528 |
}
|
|
529 |
|
|
530 |
@Override
|
|
531 |
public void accept(double t) {
|
|
532 |
state = operator.applyAsDouble(state, t);
|
|
533 |
}
|
|
534 |
|
|
535 |
@Override
|
|
536 |
public Double get() {
|
|
537 |
return state;
|
|
538 |
}
|
|
539 |
|
|
540 |
@Override
|
|
541 |
public void combine(ReducingSink other) {
|
|
542 |
accept(other.state);
|
|
543 |
}
|
|
544 |
}
|
|
545 |
return new ReduceOp<Double, Double, ReducingSink>(StreamShape.DOUBLE_VALUE) {
|
|
546 |
@Override
|
|
547 |
public ReducingSink makeSink() {
|
|
548 |
return new ReducingSink();
|
|
549 |
}
|
|
550 |
};
|
|
551 |
}
|
|
552 |
|
|
553 |
/**
|
|
554 |
* Constructs a {@code TerminalOp} that implements a functional reduce on
|
|
555 |
* {@code double} values, producing an optional double result.
|
|
556 |
*
|
|
557 |
* @param operator the combining function
|
|
558 |
* @return a {@code TerminalOp} implementing the reduction
|
|
559 |
*/
|
|
560 |
public static TerminalOp<Double, OptionalDouble>
|
|
561 |
makeDouble(DoubleBinaryOperator operator) {
|
|
562 |
Objects.requireNonNull(operator);
|
|
563 |
class ReducingSink
|
|
564 |
implements AccumulatingSink<Double, OptionalDouble, ReducingSink>, Sink.OfDouble {
|
|
565 |
private boolean empty;
|
|
566 |
private double state;
|
|
567 |
|
|
568 |
public void begin(long size) {
|
|
569 |
empty = true;
|
|
570 |
state = 0;
|
|
571 |
}
|
|
572 |
|
|
573 |
@Override
|
|
574 |
public void accept(double t) {
|
|
575 |
if (empty) {
|
|
576 |
empty = false;
|
|
577 |
state = t;
|
|
578 |
}
|
|
579 |
else {
|
|
580 |
state = operator.applyAsDouble(state, t);
|
|
581 |
}
|
|
582 |
}
|
|
583 |
|
|
584 |
@Override
|
|
585 |
public OptionalDouble get() {
|
|
586 |
return empty ? OptionalDouble.empty() : OptionalDouble.of(state);
|
|
587 |
}
|
|
588 |
|
|
589 |
@Override
|
|
590 |
public void combine(ReducingSink other) {
|
|
591 |
if (!other.empty)
|
|
592 |
accept(other.state);
|
|
593 |
}
|
|
594 |
}
|
|
595 |
return new ReduceOp<Double, OptionalDouble, ReducingSink>(StreamShape.DOUBLE_VALUE) {
|
|
596 |
@Override
|
|
597 |
public ReducingSink makeSink() {
|
|
598 |
return new ReducingSink();
|
|
599 |
}
|
|
600 |
};
|
|
601 |
}
|
|
602 |
|
|
603 |
/**
|
|
604 |
* Constructs a {@code TerminalOp} that implements a mutable reduce on
|
|
605 |
* {@code double} values.
|
|
606 |
*
|
|
607 |
* @param <R> the type of the result
|
|
608 |
* @param supplier a factory to produce a new accumulator of the result type
|
|
609 |
* @param accumulator a function to incorporate an int into an
|
|
610 |
* accumulator
|
|
611 |
* @param combiner a function to combine an accumulator into another
|
|
612 |
* @return a {@code TerminalOp} implementing the reduction
|
|
613 |
*/
|
|
614 |
public static <R> TerminalOp<Double, R>
|
|
615 |
makeDouble(Supplier<R> supplier,
|
|
616 |
ObjDoubleConsumer<R> accumulator,
|
|
617 |
BinaryOperator<R> combiner) {
|
|
618 |
Objects.requireNonNull(supplier);
|
|
619 |
Objects.requireNonNull(accumulator);
|
|
620 |
Objects.requireNonNull(combiner);
|
|
621 |
class ReducingSink extends Box<R>
|
|
622 |
implements AccumulatingSink<Double, R, ReducingSink>, Sink.OfDouble {
|
|
623 |
@Override
|
|
624 |
public void begin(long size) {
|
|
625 |
state = supplier.get();
|
|
626 |
}
|
|
627 |
|
|
628 |
@Override
|
|
629 |
public void accept(double t) {
|
|
630 |
accumulator.accept(state, t);
|
|
631 |
}
|
|
632 |
|
|
633 |
@Override
|
|
634 |
public void combine(ReducingSink other) {
|
|
635 |
state = combiner.apply(state, other.state);
|
|
636 |
}
|
|
637 |
}
|
|
638 |
return new ReduceOp<Double, R, ReducingSink>(StreamShape.DOUBLE_VALUE) {
|
|
639 |
@Override
|
|
640 |
public ReducingSink makeSink() {
|
|
641 |
return new ReducingSink();
|
|
642 |
}
|
|
643 |
};
|
|
644 |
}
|
|
645 |
|
|
646 |
/**
|
|
647 |
* A type of {@code TerminalSink} that implements an associative reducing
|
|
648 |
* operation on elements of type {@code T} and producing a result of type
|
|
649 |
* {@code R}.
|
|
650 |
*
|
|
651 |
* @param <T> the type of input element to the combining operation
|
|
652 |
* @param <R> the result type
|
|
653 |
* @param <K> the type of the {@code AccumulatingSink}.
|
|
654 |
*/
|
|
655 |
private interface AccumulatingSink<T, R, K extends AccumulatingSink<T, R, K>>
|
|
656 |
extends TerminalSink<T, R> {
|
|
657 |
public void combine(K other);
|
|
658 |
}
|
|
659 |
|
|
660 |
/**
|
|
661 |
* State box for a single state element, used as a base class for
|
|
662 |
* {@code AccumulatingSink} instances
|
|
663 |
*
|
|
664 |
* @param <U> The type of the state element
|
|
665 |
*/
|
|
666 |
private static abstract class Box<U> {
|
|
667 |
U state;
|
|
668 |
|
|
669 |
Box() {} // Avoid creation of special accessor
|
|
670 |
|
|
671 |
public U get() {
|
|
672 |
return state;
|
|
673 |
}
|
|
674 |
}
|
|
675 |
|
|
676 |
/**
|
|
677 |
* A {@code TerminalOp} that evaluates a stream pipeline and sends the
|
|
678 |
* output into an {@code AccumulatingSink}, which performs a reduce
|
|
679 |
* operation. The {@code AccumulatingSink} must represent an associative
|
|
680 |
* reducing operation.
|
|
681 |
*
|
|
682 |
* @param <T> the output type of the stream pipeline
|
|
683 |
* @param <R> the result type of the reducing operation
|
|
684 |
* @param <S> the type of the {@code AccumulatingSink}
|
|
685 |
*/
|
|
686 |
private static abstract class ReduceOp<T, R, S extends AccumulatingSink<T, R, S>>
|
|
687 |
implements TerminalOp<T, R> {
|
|
688 |
private final StreamShape inputShape;
|
|
689 |
|
|
690 |
/**
|
|
691 |
* Create a {@code ReduceOp} of the specified stream shape which uses
|
|
692 |
* the specified {@code Supplier} to create accumulating sinks.
|
|
693 |
*
|
|
694 |
* @param shape The shape of the stream pipeline
|
|
695 |
*/
|
|
696 |
ReduceOp(StreamShape shape) {
|
|
697 |
inputShape = shape;
|
|
698 |
}
|
|
699 |
|
|
700 |
public abstract S makeSink();
|
|
701 |
|
|
702 |
@Override
|
|
703 |
public StreamShape inputShape() {
|
|
704 |
return inputShape;
|
|
705 |
}
|
|
706 |
|
|
707 |
@Override
|
|
708 |
public <P_IN> R evaluateSequential(PipelineHelper<T> helper,
|
|
709 |
Spliterator<P_IN> spliterator) {
|
|
710 |
return helper.wrapAndCopyInto(makeSink(), spliterator).get();
|
|
711 |
}
|
|
712 |
|
|
713 |
@Override
|
|
714 |
public <P_IN> R evaluateParallel(PipelineHelper<T> helper,
|
|
715 |
Spliterator<P_IN> spliterator) {
|
|
716 |
return new ReduceTask<>(this, helper, spliterator).invoke().get();
|
|
717 |
}
|
|
718 |
}
|
|
719 |
|
|
720 |
/**
|
|
721 |
* A {@code ForkJoinTask} for performing a parallel reduce operation.
|
|
722 |
*/
|
|
723 |
private static final class ReduceTask<P_IN, P_OUT, R,
|
|
724 |
S extends AccumulatingSink<P_OUT, R, S>>
|
|
725 |
extends AbstractTask<P_IN, P_OUT, S, ReduceTask<P_IN, P_OUT, R, S>> {
|
|
726 |
private final ReduceOp<P_OUT, R, S> op;
|
|
727 |
|
|
728 |
ReduceTask(ReduceOp<P_OUT, R, S> op,
|
|
729 |
PipelineHelper<P_OUT> helper,
|
|
730 |
Spliterator<P_IN> spliterator) {
|
|
731 |
super(helper, spliterator);
|
|
732 |
this.op = op;
|
|
733 |
}
|
|
734 |
|
|
735 |
ReduceTask(ReduceTask<P_IN, P_OUT, R, S> parent,
|
|
736 |
Spliterator<P_IN> spliterator) {
|
|
737 |
super(parent, spliterator);
|
|
738 |
this.op = parent.op;
|
|
739 |
}
|
|
740 |
|
|
741 |
@Override
|
|
742 |
protected ReduceTask<P_IN, P_OUT, R, S> makeChild(Spliterator<P_IN> spliterator) {
|
|
743 |
return new ReduceTask<>(this, spliterator);
|
|
744 |
}
|
|
745 |
|
|
746 |
@Override
|
|
747 |
protected S doLeaf() {
|
|
748 |
return helper.wrapAndCopyInto(op.makeSink(), spliterator);
|
|
749 |
}
|
|
750 |
|
|
751 |
@Override
|
|
752 |
public void onCompletion(CountedCompleter caller) {
|
|
753 |
if (!isLeaf()) {
|
|
754 |
S leftResult = leftChild.getLocalResult();
|
|
755 |
leftResult.combine(rightChild.getLocalResult());
|
|
756 |
setLocalResult(leftResult);
|
|
757 |
}
|
|
758 |
// GC spliterator, left and right child
|
|
759 |
super.onCompletion(caller);
|
|
760 |
}
|
|
761 |
}
|
|
762 |
}
|