compact1, compact2, compact3

java.util

Class LongSummaryStatistics

java.lang.Object

java.util.LongSummaryStatistics

All Implemented Interfaces:

IntConsumer, LongConsumer

public class LongSummaryStatistics
extends Object
implements LongConsumer, IntConsumer

A state object for collecting statistics such as count, min, max, sum, and average.

This class is designed to work with (though does not require) streams. For example, you can compute summary statistics on a stream of longs with:

 
 LongSummaryStatistics stats = longStream.collect(LongSummaryStatistics::new,
                                                  LongSummaryStatistics::accept,
                                                  LongSummaryStatistics::combine);
 

LongSummaryStatistics can be used as a Stream.collect(Collector) reduction} target for a stream. For example:

 
 LongSummaryStatistics stats = people.stream()
                                     .collect(Collectors.summarizingLong(Person::getAge));

This computes, in a single pass, the count of people, as well as the minimum, maximum, sum, and average of their ages.

Implementation Note:

This implementation is not thread safe. However, it is safe to use Collectors.toLongStatistics() on a parallel stream, because the parallel implementation of Stream.collect() provides the necessary partitioning, isolation, and merging of results for safe and efficient parallel execution.

This implementation does not check for overflow of the sum.

Since:

1.8

Constructor Summary

Constructors

Constructor	Description
LongSummaryStatistics()	Construct an empty instance with zero count, zero sum, Long.MAX_VALUE min, Long.MIN_VALUE max and zero average.

Method Summary

Modifier and Type	Method	Description
void