org.nd4j.common.primitives

Class Optional<T>

java.lang.Object

org.nd4j.common.primitives.Optional<T>

Type Parameters:

T - Type for optional

public class Optional<T>
extends Object

Simple Optional class, based loosely on Java 8's optional class

Author:

Alex Black

Method Summary

Modifier and Type	Method and Description
static <T> Optional<T>	empty() Returns an empty Optional instance.
T	get() If a value is present in this Optional, returns the value, otherwise throws NoSuchElementException.
boolean	isPresent() Return true if there is a value present, otherwise false.
static <T> Optional<T>	of(T value) Returns an Optional with the specified present non-null value.
static <T> Optional<T>	ofNullable(T value) Returns an Optional describing the specified value, if non-null, otherwise returns an empty Optional.
T	orElse(T other) Return the value if present, otherwise return other.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Method Detail

empty

public static <T> Optional<T> empty()

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

of

public static <T> Optional<T> of(@NonNull
                                 T value)

Returns an Optional with the specified present non-null value.

Parameters:

value - the value to be present, which must be non-null

Returns:

an Optional with the value present

ofNullable

public static <T> Optional<T> ofNullable(T value)

Returns an Optional describing the specified value, if non-null, otherwise returns an empty Optional.

Parameters:

value - the possibly-null value to describe

Returns:

an Optional with a present value if the specified value is non-null, otherwise an empty Optional

get

public T get()

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

Returns:

the non-null value held by this Optional

Throws:

NoSuchElementException - - if there is no value present

isPresent

public boolean isPresent()

Return true if there is a value present, otherwise false.

Returns:

true if there is a value present, otherwise false

orElse

public T orElse(T other)

Return the value if present, otherwise return other.

Parameters:

other - the value to be returned if there is no value present, may be null

Returns:

toString

public String toString()

Overrides:

toString in class Object