| Package | Description |
|---|---|
| java8.util |
Provides some of the new
java.util classes and implementations
of static and default interface methods added in Java 8. |
| java8.util.stream |
Classes to support functional-style operations on streams of elements, such
as map-reduce transformations on collections.
|
| Modifier and Type | Method and Description |
|---|---|
static <T> java.util.Comparator<T> |
Comparators.comparingLong(ToLongFunction<? super T> keyExtractor)
Accepts a function that extracts a
long sort key from a type
T, and returns a Comparator<T> that compares by that
sort key. |
static <T> java.util.Comparator<T> |
Comparators.thenComparingLong(java.util.Comparator<? super T> this_,
ToLongFunction<? super T> keyExtractor)
Returns a lexicographic-order comparator with a function that
extracts a
long sort key. |
| Modifier and Type | Method and Description |
|---|---|
static <T> Collector<T,?,java.lang.Double> |
Collectors.averagingLong(ToLongFunction<? super T> mapper)
Returns a
Collector that produces the arithmetic mean of a long-valued
function applied to the input elements. |
LongStream |
Stream.mapToLong(ToLongFunction<? super T> mapper)
Returns a
LongStream consisting of the results of applying the
given function to the elements of this stream. |
static <T> Collector<T,?,LongSummaryStatistics> |
Collectors.summarizingLong(ToLongFunction<? super T> mapper)
Returns a
Collector which applies an long-producing
mapping function to each input element, and returns summary statistics
for the resulting values. |
static <T> Collector<T,?,java.lang.Long> |
Collectors.summingLong(ToLongFunction<? super T> mapper)
Returns a
Collector that produces the sum of a long-valued
function applied to the input elements. |