Uses of Class java.util.OptionalLong (Java SE 9 & JDK 9 )

## Uses of Class
java.util.OptionalLong

- Packages that use OptionalLong
  Package | Description
  --- | ---
  java.util | Contains the collections framework, some internationalization support classes, a service loader, properties, random number generation, string parsing and scanning classes, base64 encoding and decoding, a bit array, and several miscellaneous utility classes.
  java.util.stream | Classes to support functional-style operations on streams of elements, such as map-reduce transformations on collections.
  jdk.incubator.http | High level HTTP and WebSocket API

- - ### Uses of OptionalLong in java.util

    Methods in java.util that return OptionalLong
    Modifier and Type | Method | Description
    --- | --- | ---
    `static OptionalLong` | OptionalLong.`empty​()` | Returns an empty `OptionalLong` instance.
    `static OptionalLong` | OptionalLong.`of​(long value)` | Returns an `OptionalLong` describing the given value.

  - ### Uses of OptionalLong in java.util.stream

    Methods in java.util.stream that return OptionalLong
    Modifier and Type | Method | Description
    --- | --- | ---
    `OptionalLong` | LongStream.`findAny​()` | Returns an `OptionalLong` describing some element of the stream, or an empty `OptionalLong` if the stream is empty.
    `OptionalLong` | LongStream.`findFirst​()` | Returns an `OptionalLong` describing the first element of this stream, or an empty `OptionalLong` if the stream is empty.
    `OptionalLong` | LongStream.`max​()` | Returns an `OptionalLong` describing the maximum element of this stream, or an empty optional if this stream is empty.
    `OptionalLong` | LongStream.`min​()` | Returns an `OptionalLong` describing the minimum element of this stream, or an empty optional if this stream is empty.
    `OptionalLong` | LongStream.`reduce​(LongBinaryOperator op)` | Performs a reduction on the elements of this stream, using an associative accumulation function, and returns an `OptionalLong` describing the reduced value, if any.

  - ### Uses of OptionalLong in jdk.incubator.http

    Methods in jdk.incubator.http that return OptionalLong
    Modifier and Type | Method | Description
    --- | --- | ---
    `OptionalLong` | HttpHeaders.`firstValueAsLong​(String name)` | Returns an `OptionalLong` containing the first value of the named header field.