| Package | Description |
|---|---|
| java.util |
Contains the collections framework, legacy collection classes, event model,
date and time facilities, internationalization, and miscellaneous utility
classes (a string tokenizer, a random-number generator, and a bit array).
|
| java.util.concurrent |
Utility classes commonly useful in concurrent programming.
|
| java.util.stream |
Classes to support functional-style operations on streams of elements, such
as map-reduce transformations on collections.
|
| Modifier and Type | Method | Description |
|---|---|---|
static <T> Comparator<T> |
Comparator.comparingInt(ToIntFunction<? super T> keyExtractor)
Accepts a function that extracts an
int sort key from a type
T, and returns a Comparator<T> that compares by that
sort key. |
|
default Comparator<T> |
Comparator.thenComparingInt(ToIntFunction<? super T> keyExtractor)
Returns a lexicographic-order comparator with a function that
extracts a
int sort key. |
| Modifier and Type | Method | Description |
|---|---|---|
int |
ConcurrentHashMap.reduceEntriesToInt(long parallelismThreshold,
ToIntFunction<Map.Entry<K,V>> transformer,
int basis,
IntBinaryOperator reducer)
Returns the result of accumulating the given transformation
of all entries using the given reducer to combine values,
and the given basis as an identity value.
|
|
int |
ConcurrentHashMap.reduceKeysToInt(long parallelismThreshold,
ToIntFunction<? super K> transformer,
int basis,
IntBinaryOperator reducer)
Returns the result of accumulating the given transformation
of all keys using the given reducer to combine values, and
the given basis as an identity value.
|
|
int |
ConcurrentHashMap.reduceValuesToInt(long parallelismThreshold,
ToIntFunction<? super V> transformer,
int basis,
IntBinaryOperator reducer)
Returns the result of accumulating the given transformation
of all values using the given reducer to combine values,
and the given basis as an identity value.
|
| Modifier and Type | Method | Description |
|---|---|---|
static <T> Collector<T,?,Double> |
Collectors.averagingInt(ToIntFunction<? super T> mapper)
Returns a
Collector that produces the arithmetic mean of an integer-valued
function applied to the input elements. |
|
IntStream |
Stream.mapToInt(ToIntFunction<? super T> mapper)
Returns an
IntStream consisting of the results of applying the
given function to the elements of this stream. |
|
static <T> Collector<T,?,IntSummaryStatistics> |
Collectors.summarizingInt(ToIntFunction<? super T> mapper)
Returns a
Collector which applies an int-producing
mapping function to each input element, and returns summary statistics
for the resulting values. |
|
static <T> Collector<T,?,Integer> |
Collectors.summingInt(ToIntFunction<? super T> mapper)
Returns a
Collector that produces the sum of a integer-valued
function applied to the input elements. |
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