Added in API level 24

java.util.stream

Interfaces

BaseStream<T, S extends BaseStream<T, S>> Base interface for streams, which are sequences of elements supporting sequential and parallel aggregate operations. 
Collector<T, A, R> A mutable reduction operation that accumulates input elements into a mutable result container, optionally transforming the accumulated result into a final representation after all input elements have been processed. 
DoubleStream A sequence of primitive double-valued elements supporting sequential and parallel aggregate operations. 
DoubleStream.Builder A mutable builder for a DoubleStream. 
IntStream A sequence of primitive int-valued elements supporting sequential and parallel aggregate operations. 
IntStream.Builder A mutable builder for an IntStream. 
LongStream A sequence of primitive long-valued elements supporting sequential and parallel aggregate operations. 
LongStream.Builder A mutable builder for a LongStream. 
Stream<T> A sequence of elements supporting sequential and parallel aggregate operations. 
Stream.Builder<T> A mutable builder for a Stream. 

Classes

Collectors Implementations of Collector that implement various useful reduction operations, such as accumulating elements into collections, summarizing elements according to various criteria, etc. 
StreamSupport Low-level utility methods for creating and manipulating streams. 

Enums

Collector.Characteristics Characteristics indicating properties of a Collector, which can be used to optimize reduction implementations.