Class Either.LeftProjection

java.lang.Object
Either<L,R>.io.atlassian.fugue.Either.AbstractProjection<L,R>
io.atlassian.fugue.Either.LeftProjection
All Implemented Interfaces:
Effect.Applicant<L>, Either.Projection<L,R,L,R>, Maybe<L>, Iterable<L>
Enclosing class:
Either<L,R>
public final class Either.LeftProjection extends Either<L,R>.AbstractProjection<L,R> implements Either.Projection<L,R,L,R>
A left projection of an either value.
Since:
1.0

  • Constructor Details

    • LeftProjection

      private LeftProjection()

  • Method Details

    • get

      public L get()
      Description copied from interface: Maybe
      Get the value if defined. Throw an exception otherwise.
      Specified by:
      get in interface Maybe<L>
      Returns:
      the wrapped value

    • isDefined

      public boolean isDefined()
      Description copied from interface: Maybe
      If the type contains a value return true.
      Specified by:
      isDefined in interface Maybe<L>
      Returns:
      true if this holds a value, false otherwise.

    • on

      public L on(Function<? super R, ? extends L> f)
      Description copied from interface: Either.Projection
      The value of this projection or the result of the given function on the opposing projection's value.
      Specified by:
      on in interface Either.Projection<L,R,L,R>
      Parameters:
      f - The function to execute if this projection has no value.
      Returns:
      The value of this projection or the result of the given function on the opposing projection's value.

    • map

      public <X> Either<X,R> map(Function<? super L, X> f)
      Map the given function across this projection's value if it has one.
      Type Parameters:
      X - the LHS type
      Parameters:
      f - The function to map across this projection, must not return null
      Returns:
      A new either value after mapping.

    • flatMap

      public <X, RR extends R> Either<X,R> flatMap(Function<? super L, Either<X,RR>> f)
      Binds the given function across this projection's value if it has one.
      Type Parameters:
      X - the LHS type
      RR - The existing RHS or a subtype
      Parameters:
      f - The function to bind across this projection.
      Returns:
      A new either value after binding.

    • toRight

      <X> Either.Right<X,R> toRight()

    • sequence

      public <X> Either<X,R> sequence(Either<X,R> e)
      Anonymous bind through this projection.
      Type Parameters:
      X - the LHS type
      Parameters:
      e - The value to bind with.
      Returns:
      An either after binding through this projection.

    • filter

      public <X> Option<Either<L,X>> filter(Predicate<? super L> f)
      Returns None if this projection has no value or if the given predicate p does not hold for the value, otherwise, returns a left in Some.
      Type Parameters:
      X - the RHS type
      Parameters:
      f - The predicate function to test on this projection's value.
      Returns:
      None if this projection has no value or if the given predicate p does not hold for the value, otherwise, returns a left in Some.

    • filterOrElse

      public Either<L,R> filterOrElse(Predicate<? super L> p, Supplier<? extends R> orElseSupplier)
      Return a Left if this is a Left and the contained values satisfies the given predicate. If this is a Left but the predicate is not satisfied, return a Right with the value provided by the orElseSupplier. Return a Right if this a Right with the contained value.
      Parameters:
      p - The predicate function to test on the right contained value.
      orElseSupplier - The supplier to execute when is a left, and predicate is unsatisfied
      Returns:
      a new Either that will be either the existing left/right or a right with result of orElseSupplier
      Since:
      4.7.0

    • ap

      public <X> Either<X,R> ap(Either<Function<L,X>, R> either)
      Function application on this projection's value.
      Type Parameters:
      X - the LHS type
      Parameters:
      either - The either of the function to apply on this projection's value.
      Returns:
      The result of function application within either.
      Since:
      3.0

    • apply

      @Deprecated public <X> Either<X,R> apply(Either<Function<L,X>, R> either)
      Deprecated.
      since 3.0
      Function application on this projection's value.
      Type Parameters:
      X - the LHS type
      Parameters:
      either - The either of the function to apply on this projection's value.
      Returns:
      The result of function application within either.
      See Also:

    • as

      <X> Either<L,X> as()
      Coerces our right type as X. Dangerous, isLeft() must be true
      Type Parameters:
      X - the type to coerce to.
      Returns:
      an either with the coerced right type.