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java.util.stream
Interfaces
| BaseStream |
Base interface for streams, which are sequences of elements supporting sequential and parallel aggregate operations.
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| Collector |
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.
|
| Gatherer |
An intermediate operation that transforms a stream of input elements into a stream of output elements, optionally applying a final action when the end of the upstream is reached.
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| IntStream |
A sequence of primitive int-valued elements supporting sequential and parallel aggregate operations.
|
| LongStream |
A sequence of primitive long-valued elements supporting sequential and parallel aggregate operations.
|
| Stream |
A sequence of elements supporting sequential and parallel aggregate operations.
|
Classes
| Collectors |
Implementations of Collector that implement various useful reduction operations, such as accumulating elements into collections, summarizing elements according to various criteria, etc.
|
| Gatherers |
Implementations of Gatherer that provide useful intermediate operations, such as windowing functions, folding functions, transforming elements concurrently, etc.
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| StreamSupport |
Low-level utility methods for creating and manipulating streams.
|
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Last updated 2025-08-20 UTC.
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-20 UTC."],[],[],null,["# java.util.stream\n================\n\nInterfaces\n----------\n\n|-----------------------------------------------------------------|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| [BaseStream](/reference/kotlin/java/util/stream/BaseStream) | Base interface for streams, which are sequences of elements supporting sequential and parallel aggregate operations. |\n| [Collector](/reference/kotlin/java/util/stream/Collector) | A [mutable reduction operation](#Reduction) 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. |\n| [DoubleStream](/reference/kotlin/java/util/stream/DoubleStream) | A sequence of primitive double-valued elements supporting sequential and parallel aggregate operations. |\n| [Gatherer](/reference/kotlin/java/util/stream/Gatherer) | An intermediate operation that transforms a stream of input elements into a stream of output elements, optionally applying a final action when the end of the upstream is reached. |\n| [IntStream](/reference/kotlin/java/util/stream/IntStream) | A sequence of primitive int-valued elements supporting sequential and parallel aggregate operations. |\n| [LongStream](/reference/kotlin/java/util/stream/LongStream) | A sequence of primitive long-valued elements supporting sequential and parallel aggregate operations. |\n| [Stream](/reference/kotlin/java/util/stream/Stream) | A sequence of elements supporting sequential and parallel aggregate operations. |\n\nClasses\n-------\n\n|-------------------------------------------------------------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|\n| [Collectors](/reference/kotlin/java/util/stream/Collectors) | Implementations of [Collector](/reference/kotlin/java/util/stream/Collector) that implement various useful reduction operations, such as accumulating elements into collections, summarizing elements according to various criteria, etc. |\n| [Gatherers](/reference/kotlin/java/util/stream/Gatherers) | Implementations of [Gatherer](/reference/kotlin/java/util/stream/Gatherer) that provide useful intermediate operations, such as windowing functions, folding functions, transforming elements concurrently, etc. |\n| [StreamSupport](/reference/kotlin/java/util/stream/StreamSupport) | Low-level utility methods for creating and manipulating streams. |"]]
