Interface Either<A,B>

All Known Implementing Classes:

Either.Left, Either.Right

public sealed interface Either<A,B>
permits Either.Left<A>, Either.Right<B>

An Either is always either an instance of Either.Left or Either.Right effectively giving a union type of two other types.

Nested Class Summary

Nested Classes

Modifier and Type	Interface	Description
static final record	Either.Left<A>
static final record	Either.Right<B>

Method Summary

Modifier and Type	Method	Description
default <T> T	get(Function<A,T> funcA, Function<B,T> funcB)	Gets a value from this Either.
default <T, E extends Throwable> T	getOrThrow(Function<A,T> funcA, Function<B, ? extends E> funcB)	Gets a value from this Either if it is a Either.Left or throws an exception if it is a Either.Right.
Optional<A>	left()	Gets the left value of this Either if this is a Either.Left.
static <A,B> Either<A,B>	left(A a)	Creates a new Either.Left either.
default <T,U> Either<T,U>	map(Function<A,T> leftMapper, Function<B,U> rightMapper)	Maps this Either with different mapper functions depending on whether this is a Either.Left or a Either.Right.
<T> Either<T,B>	mapLeft(Function<A,T> mapper)	Maps this Either if it is a Either.Left.
<T> Either<A,T>	mapRight(Function<B,T> mapper)	Maps this Either if it is a Either.Right.
Optional<B>	right()	Gets the right value of this Either if this is a Either.Right.
static <A,B> Either<A,B>	right(B b)	Creates a new Either.Right either.
Either<B,A>	swap()	Swaps the order of the elements.
static <T> Either<T, RuntimeException>	tryWith(Supplier<T> action)	Executes the given Supplier and returns a Either.Left with the result.

Method Details

left

Optional<A> left()

Gets the left value of this Either if this is a Either.Left.

right

Optional<B> right()

Gets the right value of this Either if this is a Either.Right.

swap

Either<B,A> swap()

Swaps the order of the elements.

mapLeft

<T> Either<T,B> mapLeft(Function<A,T> mapper)

Maps this Either if it is a Either.Left.

mapRight

<T> Either<A,T> mapRight(Function<B,T> mapper)

Maps this Either if it is a Either.Right.

map

default <T,U> Either<T,U> map(Function<A,T> leftMapper,
 Function<B,U> rightMapper)

Maps this Either with different mapper functions depending on whether this is a Either.Left or a Either.Right.

get

default <T> T get(Function<A,T> funcA,
 Function<B,T> funcB)

Gets a value from this Either.

getOrThrow

default <T, E extends Throwable> T getOrThrow(Function<A,T> funcA,
 Function<B, ? extends E> funcB)
                                       throws E

Gets a value from this Either if it is a Either.Left or throws an exception if it is a Either.Right.

Throws:

E

left

static <A,B> Either<A,B> left(A a)

Creates a new Either.Left either.

right

static <A,B> Either<A,B> right(B b)

Creates a new Either.Right either.

tryWith

static <T> Either<T, RuntimeException> tryWith(Supplier<T> action)

Executes the given Supplier and returns a Either.Left with the result. If the supplier throws an exception, returns a Either.Right containing that exception.