public class IntSummaryStatistics extends Object implements 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 ints with:
IntSummaryStatistics stats = intStream.collect(IntSummaryStatistics::new, IntSummaryStatistics::accept, IntSummaryStatistics::combine);
IntSummaryStatistics
can be used as a reduction target for a stream. For example:
IntSummaryStatistics stats = people.stream() .collect(Collectors.summarizingInt(Person::getDependents));This computes, in a single pass, the count of people, as well as the minimum, maximum, sum, and average of their number of dependents.
Collectors.toIntStatistics()
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.
public IntSummaryStatistics()
Construct an empty instance with zero count, zero sum, Integer.MAX_VALUE
min, Integer.MIN_VALUE
max and zero average.
public void accept(int value)
Records a new value into the summary information
accept
in interface IntConsumer
value
- the input valuepublic void combine(IntSummaryStatistics other)
Combines the state of another IntSummaryStatistics
into this one.
other
- another IntSummaryStatistics
NullPointerException
- if other
is nullpublic final long getCount()
Returns the count of values recorded.
public final long getSum()
Returns the sum of values recorded, or zero if no values have been recorded.
public final int getMin()
Returns the minimum value recorded, or Integer.MAX_VALUE
if no values have been recorded.
Integer.MAX_VALUE
if nonepublic final int getMax()
Returns the maximum value recorded, or Integer.MIN_VALUE
if no values have been recorded.
Integer.MIN_VALUE
if nonepublic final double getAverage()
Returns the arithmetic mean of values recorded, or zero if no values have been recorded.
public String toString()
Description copied from class: Object
Returns a string representation of the object. In general, the toString
method returns a string that "textually represents" this object. The result should be a concise but informative representation that is easy for a person to read. It is recommended that all subclasses override this method.
The toString
method for class Object
returns a string consisting of the name of the class of which the object is an instance, the at-sign character `@
', and the unsigned hexadecimal representation of the hash code of the object. In other words, this method returns a string equal to the value of:
getClass().getName() + '@' + Integer.toHexString(hashCode())
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Documentation extracted from Debian's OpenJDK Development Kit package.
Licensed under the GNU General Public License, version 2, with the Classpath Exception.
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