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() [ADDED]

  • 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]

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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