Package software.amazon.awssdk.utils

Class Either<L,​R>

  • Type Parameters:
    L - Left type
    R - Right type
    public final class Either<L,​R>
extends Object
    Represents a value that can be one of two types.

    • Method Detail

      • map

        public <T> T map​(Function<? super L,​? extends T> lFunc,
                 Function<? super R,​? extends T> rFunc)
        Maps the Either to a type and returns the resolved value (which may be from the left or the right value).
        Type Parameters:
        T - Type that both the left and right should be mapped to.
        Parameters:
        lFunc - Function that maps the left value if present.
        rFunc - Function that maps the right value if present.
        Returns:
        Mapped value from either lFunc or rFunc depending on which value is present.

      • mapLeft

        public <T> Either<T,​R> mapLeft​(Function<? super L,​? extends T> lFunc)
        Map the left most value and return a new Either reflecting the new types.
        Type Parameters:
        T - New type of left value.
        Parameters:
        lFunc - Function that maps the left value if present.
        Returns:
        New Either bound to the new left type and the same right type.

      • mapRight

        public <T> Either<L,​T> mapRight​(Function<? super R,​? extends T> rFunc)
        Map the right most value and return a new Either reflecting the new types.
        Type Parameters:
        T - New type of right value.
        Parameters:
        rFunc - Function that maps the right value if present.
        Returns:
        New Either bound to the same left type and the new right type.

      • apply

        public void apply​(Consumer<? super L> lFunc,
                  Consumer<? super R> rFunc)
        Apply the consumers to the left or the right value depending on which is present.
        Parameters:
        lFunc - Consumer of left value, invoked if left value is present.
        rFunc - Consumer of right value, invoked if right value is present.

      • left

        public static <L,​R> Either<L,​R> left​(L value)
        Create a new Either with the left type.
        Type Parameters:
        L - Left type
        R - Right type
        Parameters:
        value - Left value

      • right

        public static <L,​R> Either<L,​R> right​(R value)
        Create a new Either with the right type.
        Type Parameters:
        L - Left type
        R - Right type
        Parameters:
        value - Right value

      • left

        public Optional<L> left()
        Returns:
        the left value

      • right

        public Optional<R> right()
        Returns:
        the right value

      • fromNullable

        public static <L,​R> Optional<Either<L,​R>> fromNullable​(L left,
                                                                   R right)
        Create a new Optional<Either> from two possibly null values. If both values are null, Optional.empty() is returned. Only one of the left or right values is allowed to be non-null, otherwise an IllegalArgumentException is thrown.
        Type Parameters:
        L - Left type
        R - Right type
        Parameters:
        left - The left value (possibly null)
        right - The right value (possibly null)
        Returns:
        an Optional Either representing one of the two values or empty if both are null

      • hashCode

        public int hashCode()
        Overrides:
        hashCode in class Object