Package Summary Overview Summary

class:OptionalInt [NONE]

```
public final class OptionalInt
extends Object
```
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; use of identity-sensitive operations (including reference equality (==), identity hash code, or synchronization) on instances of OptionalInt may have unpredictable results and should be avoided.

API Note:

OptionalInt is primarily intended for use as a method return type where there is a clear need to represent "no result." A variable whose type is OptionalInt should never itself be null; it should always point to an OptionalInt instance.

Since:

1.8

method:empty() [NONE]

empty
```
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 == against instances returned by OptionalInt.empty(). There is no guarantee that it is a singleton. Instead, use isPresent().

Returns:

an empty OptionalInt

method:of(int) [NONE]

of
```
public static OptionalInt of(int value)
```
Returns an OptionalInt describing the given value.

Parameters:

value - the value to describe

Returns:

an OptionalInt with the value present

method:getAsInt() [NONE]

getAsInt
```
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:

the value described by this OptionalInt

Throws:

NoSuchElementException - if no value is present

method:isPresent() [NONE]

isPresent
```
public boolean isPresent()
```
If a value is present, returns true, otherwise false.

Returns:

true if a value is present, otherwise false

method:isEmpty() [NONE]

isEmpty
```
public boolean isEmpty()
```
If a value is not present, returns true, otherwise false.

Returns:

true if a value is not present, otherwise false

Since:

11

method:ifPresent(java.util.function.IntConsumer) [NONE]

ifPresent
```
public void ifPresent(IntConsumer action)
```
If a value is present, performs the given action with the value, otherwise does nothing.

Parameters:

action - the action to be performed, if a value is present

Throws:

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

method:ifPresentOrElse(java.util.function.IntConsumer,java.lang.Runnable) [NONE]

ifPresentOrElse
```
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 - the action to be performed, if a value is present

emptyAction - 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.

Since:

9

method:stream() [NONE]

stream
```
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:

the optional value as an IntStream

Since:

9

method:orElse(int) [NONE]

orElse
```
public int orElse(int other)
```
If a value is present, returns the value, otherwise returns other.

Parameters:

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

Returns:

the value, if present, otherwise other

method:orElseGet(java.util.function.IntSupplier) [NONE]

orElseGet
```
public int orElseGet(IntSupplier supplier)
```
If a value is present, returns the value, otherwise returns the result produced by the supplying function.

Parameters:

supplier - the supplying function that produces a value to be returned

Returns:

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

method:orElseThrow() [NONE]

orElseThrow
```
public int orElseThrow()
```
If a value is present, returns the value, otherwise throws NoSuchElementException.

Returns:

the value described by this OptionalInt

Throws:

NoSuchElementException - if no value is present

Since:

10

method:orElseThrow(java.util.function.Supplier) [NONE]

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

Type Parameters:

X - Type of the exception to be thrown

Parameters:

exceptionSupplier - the supplying function that produces an exception to be thrown

Returns:

the value, if present

Throws:

X - if no value is present

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

X extends Throwable

method:equals(java.lang.Object) [NONE]

equals
```
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 ==.
Overrides:

equals in class Object

Parameters:

obj - an object to be tested for equality

Returns:

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

See Also:

Object.hashCode(), HashMap

method:hashCode() [NONE]

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

Overrides:

hashCode in class Object

Returns:

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

See Also:

Object.equals(java.lang.Object), System.identityHashCode(java.lang.Object)

method:toString() [NONE]

toString
```
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.

Overrides:

toString in class Object

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:

the string representation of this instance

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