Added in API level 24

OptionalLong

class OptionalLong

kotlin.Any
↳	java.util.OptionalLong

A container object which may or may not contain a long value. If a value is present, isPresent() returns true. If no value is present, the object is considered empty and isPresent() returns false.

Additional methods that depend on the presence or absence of a contained value are provided, such as orElse() (returns a default value if no value is present) and ifPresent() (performs an action if a value is present).

This is a value-based class; programmers should treat instances that are equal as interchangeable and should not use instances for synchronization, or unpredictable behavior may occur. For example, in a future release, synchronization may fail.

Summary

Public methods
static OptionalLong!	`empty()` Returns an empty `OptionalLong` instance.
Boolean	`equals(other: Any?)` Indicates whether some other object is "equal to" this `OptionalLong`.
Long	`getAsLong()` If a value is present, returns the value, otherwise throws `NoSuchElementException`.
Int	`hashCode()` Returns the hash code of the value, if present, otherwise `0` (zero) if no value is present.
Unit	`ifPresent(action: LongConsumer!)` If a value is present, performs the given action with the value, otherwise does nothing.
Unit	`ifPresentOrElse(action: LongConsumer!, emptyAction: Runnable!)` If a value is present, performs the given action with the value, otherwise performs the given empty-based action.
Boolean	`isEmpty()` If a value is not present, returns `true`, otherwise `false`.
Boolean	`isPresent()` If a value is present, returns `true`, otherwise `false`.
static OptionalLong!	`of(value: Long)` Returns an `OptionalLong` describing the given value.
Long	`orElse(other: Long)` If a value is present, returns the value, otherwise returns `other`.
Long	`orElseGet(supplier: LongSupplier!)` If a value is present, returns the value, otherwise returns the result produced by the supplying function.
Long	`orElseThrow()` If a value is present, returns the value, otherwise throws `NoSuchElementException`.
Long	`orElseThrow(exceptionSupplier: Supplier<out X>!)` If a value is present, returns the value, otherwise throws an exception produced by the exception supplying function.
LongStream!	`stream()` If a value is present, returns a sequential `LongStream` containing only that value, otherwise returns an empty `LongStream`.
String	`toString()` Returns a non-empty string representation of this `OptionalLong` suitable for debugging.

Public methods

empty

Added in API level 24

static fun empty(): OptionalLong!

Returns an empty OptionalLong instance. No value is present for this OptionalLong.

Return
`OptionalLong!`	an empty `OptionalLong`.

equals

Added in API level 24

fun equals(other: Any?): Boolean

Indicates whether some other object is "equal to" this OptionalLong. The other object is considered equal if:

it is also an OptionalLong and;
both instances have no value present or;
the present values are "equal to" each other via ==.

Parameters
`obj`	an object to be tested for equality

Return
`Boolean`	`true` if the other object is "equal to" this object otherwise `false`

getAsLong

Added in API level 24

fun getAsLong(): Long

If a value is present, returns the value, otherwise throws NoSuchElementException.

Return
`Long`	the value described by this `OptionalLong`

Exceptions
`java.util.NoSuchElementException`	if no value is present

hashCode

Added in API level 24

fun hashCode(): Int

Returns the hash code of the value, if present, otherwise 0 (zero) if no value is present.

Return
`Int`	hash code value of the present value or `0` if no value is present

ifPresent

Added in API level 24

fun ifPresent(action: LongConsumer!): Unit

If a value is present, performs the given action with the value, otherwise does nothing.

Parameters
`action`	LongConsumer!: the action to be performed, if a value is present

Exceptions
`java.lang.NullPointerException`	if value is present and the given action is `null`

ifPresentOrElse

Added in API level 33

fun ifPresentOrElse(
    action: LongConsumer!, 
    emptyAction: Runnable!
): Unit

If a value is present, performs the given action with the value, otherwise performs the given empty-based action.

Parameters
`action`	LongConsumer!: the action to be performed, if a value is present
`emptyAction`	Runnable!: the empty-based action to be performed, if no value is present

Exceptions
`java.lang.NullPointerException`	if a value is present and the given action is `null`, or no value is present and the given empty-based action is `null`.

isEmpty

Added in API level 33

fun isEmpty(): Boolean

If a value is not present, returns true, otherwise false.

Return
`Boolean`	`true` if a value is not present, otherwise `false`

isPresent

Added in API level 24

fun isPresent(): Boolean

If a value is present, returns true, otherwise false.

Return
`Boolean`	`true` if a value is present, otherwise `false`

of

Added in API level 24

static fun of(value: Long): OptionalLong!

Returns an OptionalLong describing the given value.

Parameters
`value`	Long: the value to describe

Return
`OptionalLong!`	an `OptionalLong` with the value present

orElse

Added in API level 24

fun orElse(other: Long): Long

If a value is present, returns the value, otherwise returns other.

Parameters
`other`	Long: the value to be returned, if no value is present

Return
`Long`	the value, if present, otherwise `other`

orElseGet

Added in API level 24

fun orElseGet(supplier: LongSupplier!): Long

If a value is present, returns the value, otherwise returns the result produced by the supplying function.

Parameters
`supplier`	LongSupplier!: the supplying function that produces a value to be returned

Return
`Long`	the value, if present, otherwise the result produced by the supplying function

Exceptions
`java.lang.NullPointerException`	if no value is present and the supplying function is `null`

orElseThrow

Added in API level 33

fun orElseThrow(): Long

If a value is present, returns the value, otherwise throws NoSuchElementException.

Return
`Long`	the value described by this `OptionalLong`

Exceptions
`java.util.NoSuchElementException`	if no value is present

orElseThrow

Added in API level 24

fun <X : Throwable!> orElseThrow(exceptionSupplier: Supplier<out X>!): Long

If a value is present, returns the value, otherwise throws an exception produced by the exception supplying function.

Parameters
`<X>`	Type of the exception to be thrown
`exceptionSupplier`	Supplier<out X>!: the supplying function that produces an exception to be thrown

Return
`Long`	the value, if present

Exceptions
`X`	if no value is present
`java.lang.NullPointerException`	if no value is present and the exception supplying function is `null`

stream

Added in API level 33

fun stream(): LongStream!

If a value is present, returns a sequential LongStream containing only that value, otherwise returns an empty LongStream.

Return
`LongStream!`	the optional value as an `LongStream`

toString

Added in API level 24

fun toString(): String

Returns a non-empty string representation of this OptionalLong suitable for debugging. The exact presentation format is unspecified and may vary between implementations and versions.

Return
`String`	the string representation of this instance