com.atlassian.confluence.impl.util

Class OptionalUtils

java.lang.Object

com.atlassian.confluence.impl.util.OptionalUtils

public final class OptionalUtils
extends Object

Utility methods relating to Optionals.

Since:

6.7.0

Method Summary

Modifier and Type	Method and Description
static <T,U> Optional<U>	first(Optional<T> maybeT, Function<? super T,Optional<U>>... mappers) Returns the first non-empty value obtained by separately applying the given mappers to the given Optional.
static <T> Optional<T>	firstNonEmpty(Supplier<Optional<T>>... lazyOptionals) Returns the first of the given Optionals that is non-empty.
static <A,B> Optional<io.atlassian.fugue.Pair<A,B>>	zip(Optional<A> o1, Optional<B> o2) Zips the two given optionals into an optional of a pair.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

zip

public static <A,B> Optional<io.atlassian.fugue.Pair<A,B>> zip(Optional<A> o1,
                                                               Optional<B> o2)

Zips the two given optionals into an optional of a pair. This method can be deleted once we're on Fugue 4.6.0 or later, when its Pair type will contain this method.

Type Parameters:

A - the first type

B - the second type

Parameters:

o1 - the first optional

o2 - the second optional

Returns:

empty if either or both optionals are empty

first

@SafeVarargs
public static <T,U> Optional<U> first(Optional<T> maybeT,
                                                   Function<? super T,Optional<U>>... mappers)

Returns the first non-empty value obtained by separately applying the given mappers to the given Optional.

Type Parameters:

T - the input type

U - the output type

Parameters:

maybeT - the optional to which to apply the mappers

mappers - the mappers to apply one by one

Returns:

empty if the given Optional is empty or all the given mappers return an empty

firstNonEmpty

@SafeVarargs
public static <T> Optional<T> firstNonEmpty(Supplier<Optional<T>>... lazyOptionals)

Returns the first of the given Optionals that is non-empty.

Type Parameters:

T - the type of value

Parameters:

lazyOptionals - the optionals to inspect

Returns:

empty if all of the given optionals are empty