• Method Summary

    empty()

    Returns an empty Optional instance.

    boolean

    Indicates whether some other object is "equal to" this Optional.

    If a value is present, and the value matches the given predicate, returns an Optional describing the value, otherwise returns an empty Optional.

    If a value is present, returns the result of applying the given Optional-bearing mapping function to the value, otherwise returns an empty Optional.

    get()

    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

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

    void

    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.

    map(Function<? super T,? extends U> mapper)

    If a value is present, returns an Optional describing (as if by ofNullable(T)) the result of applying the given mapping function to the value, otherwise returns an empty Optional.

    of(T value)

    Returns an Optional describing the given non-null value.

    ofNullable(T value)

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

    If a value is present, returns an Optional describing the value, otherwise returns an Optional produced by the supplying function.

    orElse(T other)

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

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

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

    orElseThrow(Supplier<? extends X> exceptionSupplier)

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

    stream()

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

    toString()

    Returns a non-empty string representation of this Optional suitable for debugging.

  • Method Details

    • empty

    • of

    • ofNullable

    • get

    • isPresent

    • isEmpty

    • ifPresent

    • ifPresentOrElse

    • filter

    • map

    • flatMap

    • or

    • stream

    • orElse

    • orElseGet

    • orElseThrow

    • orElseThrow

    • equals

    • hashCode

    • toString