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	/*
	* Copyright (c) 2012, 2013, 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;

	import java.util.function.IntConsumer;
	import java.util.function.LongConsumer;
	import java.util.stream.Collector;

	/**
	* A state object for collecting statistics such as count, min, max, sum, and
	* average.
	*
	* <p>This class is designed to work with (though does not require)
	* {@linkplain java.util.stream streams}. For example, you can compute
	* summary statistics on a stream of longs with:
	* <pre> {@code
	* LongSummaryStatistics stats = longStream.collect(LongSummaryStatistics::new,
	* LongSummaryStatistics::accept,
	* LongSummaryStatistics::combine);
	* }</pre>
	*
	* <p>{@code LongSummaryStatistics} can be used as a
	* {@linkplain java.util.stream.Stream#collect(Collector)} reduction}
	* target for a {@linkplain java.util.stream.Stream stream}. For example:
	*
	* <pre> {@code
	* LongSummaryStatistics stats = people.stream()
	* .collect(Collectors.summarizingLong(Person::getAge));
	*}</pre>
	*
	* This computes, in a single pass, the count of people, as well as the minimum,
	* maximum, sum, and average of their ages.
	*
	* @implNote This implementation is not thread safe. However, it is safe to use
	* {@link java.util.stream.Collectors#summarizingLong(java.util.function.ToLongFunction)
	* Collectors.toLongStatistics()} on a parallel stream, because the parallel
	* implementation of {@link java.util.stream.Stream#collect Stream.collect()}
	* provides the necessary partitioning, isolation, and merging of results for
	* safe and efficient parallel execution.
	*
	* <p>This implementation does not check for overflow of the sum.
	* @since 1.8
	*/
	public class LongSummaryStatistics implements LongConsumer, IntConsumer {
	private long count;
	private long sum;
	private long min = Long.MAX_VALUE;
	private long max = Long.MIN_VALUE;

	/**
	* Construct an empty instance with zero count, zero sum,
	* {@code Long.MAX_VALUE} min, {@code Long.MIN_VALUE} max and zero
	* average.
	*/
	public LongSummaryStatistics() { }

	/**
	* Records a new {@code int} value into the summary information.
	*
	* @param value the input value
	*/
	@Override
	public void accept(int value) {
	accept((long) value);
	}

	/**
	* Records a new {@code long} value into the summary information.
	*
	* @param value the input value
	*/
	@Override
	public void accept(long value) {
	++count;
	sum += value;
	min = Math.min(min, value);
	max = Math.max(max, value);
	}

	/**
	* Combines the state of another {@code LongSummaryStatistics} into this
	* one.
	*
	* @param other another {@code LongSummaryStatistics}
	* @throws NullPointerException if {@code other} is null
	*/
	public void combine(LongSummaryStatistics other) {
	count += other.count;
	sum += other.sum;
	min = Math.min(min, other.min);
	max = Math.max(max, other.max);
	}

	/**
	* Returns the count of values recorded.
	*
	* @return the count of values
	*/
	public final long getCount() {
	return count;
	}

	/**
	* Returns the sum of values recorded, or zero if no values have been
	* recorded.
	*
	* @return the sum of values, or zero if none
	*/
	public final long getSum() {
	return sum;
	}

	/**
	* Returns the minimum value recorded, or {@code Long.MAX_VALUE} if no
	* values have been recorded.
	*
	* @return the minimum value, or {@code Long.MAX_VALUE} if none
	*/
	public final long getMin() {
	return min;
	}

	/**
	* Returns the maximum value recorded, or {@code Long.MIN_VALUE} if no
	* values have been recorded
	*
	* @return the maximum value, or {@code Long.MIN_VALUE} if none
	*/
	public final long getMax() {
	return max;
	}

	/**
	* Returns the arithmetic mean of values recorded, or zero if no values have been
	* recorded.
	*
	* @return The arithmetic mean of values, or zero if none
	*/
	public final double getAverage() {
	return getCount() > 0 ? (double) getSum() / getCount() : 0.0d;
	}

	@Override
	/**
	* {@inheritDoc}
	*
	* Returns a non-empty string representation of this object suitable for
	* debugging. The exact presentation format is unspecified and may vary
	* between implementations and versions.
	*/
	public String toString() {
	return String.format(
	"%s{count=%d, sum=%d, min=%d, average=%f, max=%d}",
	this.getClass().getSimpleName(),
	getCount(),
	getSum(),
	getMin(),
	getAverage(),
	getMax());
	}
	}

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