Package com.dudko.tools.safejavastreams.extensions

Class EitherExtensions

java.lang.Object

com.dudko.tools.safejavastreams.extensions.EitherExtensions

public final class EitherExtensions
extends Object

Utility methods to convert from other types to Either.

Constructor Summary

Constructors

Modifier	Constructor	Description
private	EitherExtensions()

Method Summary

Modifier and Type	Method	Description
static <L, R> Either<L,R>	fromChecked(Supplier<R> supplier, Function<Throwable,? extends L> errorMapper)	Wraps a Supplier that may throw, producing an Either.
static <L, R> Either<L,R>	fromFuture(CompletableFuture<R> future, Function<Throwable,? extends L> errorMapper)	Converts a CompletableFuture to an Either.
static <L, R> Either<L,R>	fromOptional(Optional<R> optional, Supplier<? extends L> leftSupplier)	Converts an Optional to an Either.
static <L, R> Either<L,R>	fromSupplier(Supplier<R> supplier, Function<Throwable,? extends L> errorMapper)	Wraps a supplier that may throw, producing an Either.

Methods inherited from class java.lang.Object

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

Constructor Details

EitherExtensions

private EitherExtensions()

Method Details

fromOptional

public static <L,
R> Either<L,R> fromOptional(Optional<R> optional,
 Supplier<? extends L> leftSupplier)

Converts an Optional to an Either.

Type Parameters:

L - type of Left (error)

R - type of Right (success)

Parameters:

optional - the optional value

leftSupplier - supplier for the Left value if Optional is empty

Returns:

Either with Right if value is present, Left otherwise

fromFuture

public static <L,
R> Either<L,R> fromFuture(CompletableFuture<R> future,
 Function<Throwable,? extends L> errorMapper)

Converts a CompletableFuture to an Either. Blocks the current thread.

Type Parameters:

L - type of Left (error)

R - type of Right (success)

Parameters:

future - the future

errorMapper - function to convert exceptions to Left

Returns:

Either with result or mapped error

fromChecked

public static <L,
R> Either<L,R> fromChecked(Supplier<R> supplier,
 Function<Throwable,? extends L> errorMapper)

Wraps a Supplier that may throw, producing an Either.

Type Parameters:

L - type of Left (error)

R - type of Right (success)

Parameters:

supplier - the supplier

errorMapper - mapper from exception to Left value

Returns:

Either with result or mapped error

fromSupplier

public static <L,
R> Either<L,R> fromSupplier(Supplier<R> supplier,
 Function<Throwable,? extends L> errorMapper)

Wraps a supplier that may throw, producing an Either.

Type Parameters:

L - the error type (Left)

R - the result type (Right)

Parameters:

supplier - the supplier to execute

errorMapper - a function mapping a Throwable to an error value

Returns:

a successful Either with the supplier's value, or a failed Either with the mapped error