OptionalInt (net.sourceforge.streamsupport:streamsupport 1.7.1 API)

java.lang.Object
- java8.util.OptionalInt

```
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 Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`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.
`int`	`orElseThrow()` If a value is present, returns the value, otherwise throws `NoSuchElementException`.
`<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.
`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.

Methods inherited from class java.lang.Object
clone, finalize, getClass, notify, notifyAll, wait, wait, wait

- Method Detail
  - 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
  - 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
  - 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
  - isPresent
```
public boolean isPresent()
```
    If a value is present, returns true, otherwise false.
    
    Returns:
    
    true if a value is present, otherwise false
  - 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
  - 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 a value is present and the given action is null
  - 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
  - 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
  - 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
  - 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
  - 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
  - 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
  - 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
  - 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
  - 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.
    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.
    
    Overrides:
    
    toString in class Object
    
    Returns:
    
    the string representation of this instance

Class OptionalInt

Method Summary

Methods inherited from class java.lang.Object

Method Detail

empty

of

getAsInt

isPresent

isEmpty

ifPresent

ifPresentOrElse

stream

orElse

orElseGet

orElseThrow

orElseThrow

equals

hashCode

toString