Added in API level 24

Summary: Methods | Inherited Methods

OptionalInt

public final class OptionalInt
extends Object

java.lang.Object
↳	java.util.OptionalInt

---

A container object which may or may not contain an int 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 OptionalInt	empty() Returns an empty OptionalInt instance.
boolean	equals(Object obj) Indicates whether some other object is "equal to" this OptionalInt.
int	getAsInt() 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.
void	ifPresent(IntConsumer action) If a value is present, performs the given action with the value, otherwise does nothing.
void	ifPresentOrElse(IntConsumer action, Runnable emptyAction) 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 OptionalInt	of(int value) Returns an OptionalInt describing the given value.
int	orElse(int other) If a value is present, returns the value, otherwise returns other.
int	orElseGet(IntSupplier supplier) If a value is present, returns the value, otherwise returns the result produced by the supplying function.
<X extends Throwable> int	orElseThrow(Supplier<? extends X> exceptionSupplier) If a value is present, returns the value, otherwise throws an exception produced by the exception supplying function.
int	orElseThrow() If a value is present, returns the value, otherwise throws NoSuchElementException.
IntStream	stream() If a value is present, returns a sequential IntStream containing only that value, otherwise returns an empty IntStream.
String	toString() Returns a non-empty string representation of this OptionalInt suitable for debugging.

Inherited methods

From class java.lang.Object Object clone() Creates and returns a copy of this object. boolean equals(Object obj) Indicates whether some other object is "equal to" this one. void finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. final Class<?> getClass() Returns the runtime class of this Object. int hashCode() Returns a hash code value for the object. final void notify() Wakes up a single thread that is waiting on this object's monitor. final void notifyAll() Wakes up all threads that are waiting on this object's monitor. String toString() Returns a string representation of the object. final void wait(long timeoutMillis, int nanos) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed. final void wait(long timeoutMillis) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed. final void wait() Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

Public methods

empty

Added in API level 24

public static OptionalInt empty ()

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

API Note:

• Though it may be tempting to do so, avoid testing if an object is empty by comparing with == or != against instances returned by OptionalInt.empty(). There is no guarantee that it is a singleton. Instead, use isEmpty() or isPresent().

Returns
OptionalInt	an empty OptionalInt

equals

Added in API level 24

public boolean equals (Object obj)

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

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

Parameters
obj	Object: an object to be tested for equality

Returns
boolean	true if the other object is "equal to" this object otherwise false

getAsInt

Added in API level 24

public int getAsInt ()

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

API Note:

• The preferred alternative to this method is orElseThrow().

Returns
int	the value described by this OptionalInt

Throws
NoSuchElementException	if no value is present

hashCode

Added in API level 24

public int hashCode ()

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

Returns
int	hash code value of the present value or 0 if no value is present

ifPresent

Added in API level 24

public void ifPresent (IntConsumer action)

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

Parameters
action	IntConsumer: the action to be performed, if a value is present

Throws
NullPointerException	if value is present and the given action is null

ifPresentOrElse

Added in API level 33

public void ifPresentOrElse (IntConsumer action, 
                Runnable emptyAction)

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

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

Throws
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

public boolean isEmpty ()

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

Returns
boolean	true if a value is not present, otherwise false

isPresent

Added in API level 24

public boolean isPresent ()

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

Returns
boolean	true if a value is present, otherwise false

of

Added in API level 24

public static OptionalInt of (int value)

Returns an OptionalInt describing the given value.

Parameters
value	int: the value to describe

Returns
OptionalInt	an OptionalInt with the value present

orElse

Added in API level 24

public int orElse (int other)

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

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

Returns
int	the value, if present, otherwise other

orElseGet

Added in API level 24

public int orElseGet (IntSupplier supplier)

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

Parameters
supplier	IntSupplier: the supplying function that produces a value to be returned

Returns
int	the value, if present, otherwise the result produced by the supplying function

Throws
NullPointerException	if no value is present and the supplying function is null

orElseThrow

Added in API level 24

public int orElseThrow (Supplier<? extends X> exceptionSupplier)

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

API Note:

• A method reference to the exception constructor with an empty argument list can be used as the supplier. For example, IllegalStateException::new

Parameters
exceptionSupplier	Supplier: the supplying function that produces an exception to be thrown

Returns
int	the value, if present

Throws
	if no value is present
NullPointerException	if no value is present and the exception supplying function is null
Throwable

orElseThrow

Added in API level 33

public int orElseThrow ()

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

Returns
int	the value described by this OptionalInt

Throws
NoSuchElementException	if no value is present

stream

Added in API level 33

public IntStream stream ()

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

API Note:

• This method can be used to transform a Stream of optional integers to an IntStream of present integers:

  Stream<OptionalInt> os = ..
       IntStream s = os.flatMapToInt(OptionalInt::stream)
   

Returns
IntStream	the optional value as an IntStream

toString

Added in API level 24

public String toString ()

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

Implementation Requirements:

• If a value is present the result must include its string representation in the result. Empty and present OptionalInts must be unambiguously differentiable.

Returns
String	the string representation of this instance