Package io.codemodder

Class Either<L,R>

java.lang.Object

io.codemodder.Either<L,R>

public class Either<L,R>
extends Object

An implementation of the Either monad. It holds a single value of two possible types.

Method Summary

Modifier and Type	Method	Description
Either<L,R>	filter(Predicate<L> pred, R orElse)	If it contains the left value, applies the Predicate pred and return an Either containing orElse if it fails.
<A> Either<A,R>	flatMap(Function<L,Either<A,R>> func)	Applies func to the right value if present and returns an Either containing the result.
<A> Either<L,A>	flatMapRight(Function<R,Either<L,A>> func)	Applies func to the right value if present and returns an Either containing the result.
static <L, R> Either<L,R>	fromOptional(Optional<L> maybe, R orElse)	Builds Either<L,R> from an Optional<L> where either it contains the value of the Optional<L> or the orElse object.
L	getLeft()	Returns the left value, may be null
R	getRight()	Returns the right value, may be null
void	ifLeftOrElse(Consumer<? super L> leftAction, Consumer<? super R> rightAction)	Applies the Consumer leftAction if it contains the left value, or the rightAction otherwise.
<A> A	ifLeftOrElseGet(Function<? super L,A> leftFunction, Function<? super R,A> rightFunction)	Returns the result of the Functions leftFunction or rightFunction.
boolean	isLeft()	Returns true if the left value is present.
boolean	isRight()	Returns true if the right value is present.
static <A, B> Either<A,B>	left(A value)	Returns an Either containing value as a left value.
<A> Either<A,R>	map(Function<L,A> func)	Applies func to the left value if present.
<A> Either<L,A>	mapRight(Function<R,A> func)	Applies func to the left value if present.
static <A, B> Either<A,B>	right(B value)	Returns an Either containing value as a right value.
String	toString()

Methods inherited from class java.lang.Object

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

Method Details

isLeft

public boolean isLeft()

Returns true if the left value is present.

isRight

public boolean isRight()

Returns true if the right value is present.

getLeft

public L getLeft()

Returns the left value, may be null

getRight

public R getRight()

Returns the right value, may be null

left

public static <A,
B> Either<A,B> left(A value)

Returns an Either containing value as a left value.

right

public static <A,
B> Either<A,B> right(B value)

Returns an Either containing value as a right value.

map

public <A> Either<A,R> map(Function<L,A> func)

Applies func to the left value if present.

flatMap

public <A> Either<A,R> flatMap(Function<L,Either<A,R>> func)

Applies func to the right value if present and returns an Either containing the result. Otherwise, returns an Either containing the left value.

mapRight

public <A> Either<L,A> mapRight(Function<R,A> func)

Applies func to the left value if present.

flatMapRight

public <A> Either<L,A> flatMapRight(Function<R,Either<L,A>> func)

Applies func to the right value if present and returns an Either containing the result. Otherwise, returns an Either containing the left value.

fromOptional

public static <L,
R> Either<L,R> fromOptional(Optional<L> maybe,
 R orElse)

Builds Either<L,R> from an Optional<L> where either it contains the value of the Optional<L> or the orElse object.

filter

public Either<L,R> filter(Predicate<L> pred,
 R orElse)

If it contains the left value, applies the Predicate pred and return an Either containing orElse if it fails. Otherwise do nothing

ifLeftOrElse

public void ifLeftOrElse(Consumer<? super L> leftAction,
 Consumer<? super R> rightAction)

Applies the Consumer leftAction if it contains the left value, or the rightAction otherwise.

ifLeftOrElseGet

public <A> A ifLeftOrElseGet(Function<? super L,A> leftFunction,
 Function<? super R,A> rightFunction)

Returns the result of the Functions leftFunction or rightFunction.

toString

public String toString()

Overrides:

toString in class Object