Interface CheckedFunction<T,​R,​E extends Throwable>

  • Type Parameters:
    T - the type of the input to the function
    R - the type of the result of the function
    E - the type of the exception thrown by the function method
    Functional Interface:
    This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

    @FunctionalInterface
    public interface CheckedFunction<T,​R,​E extends Throwable>
    Represents a function that accepts one argument and produces a result that can throw checked exception.

    This is a functional interface whose functional method is apply(Object).

    • Method Detail

      • apply

        R apply​(T t)
         throws E extends Throwable
        Applies this function to the given argument.
        Parameters:
        t - the function argument
        Returns:
        the function result
        Throws:
        E extends Throwable
      • compose

        default <V> CheckedFunction<V,​R,​E> compose​(Function<? super V,​? extends T> before)
                                                        throws E extends Throwable
        Returns a composed function that first applies the before function to its input, and then applies this function to the result. If evaluation of either function throws an exception, it is relayed to the caller of the composed function.
        Type Parameters:
        V - the type of input to the before function, and to the composed function
        Parameters:
        before - the function to apply before this function is applied
        Returns:
        a composed function that first applies the before function and then applies this function
        Throws:
        NullPointerException - if before is null
        E extends Throwable
        See Also:
        andThen(Function)
      • andThen

        default <V> CheckedFunction<T,​V,​E> andThen​(Function<? super R,​? extends V> after)
        Returns a composed function that first applies this function to its input, and then applies the after function to the result. If evaluation of either function throws an exception, it is relayed to the caller of the composed function.
        Type Parameters:
        V - the type of output of the after function, and of the composed function
        Parameters:
        after - the function to apply after this function is applied
        Returns:
        a composed function that first applies this function and then applies the after function
        Throws:
        NullPointerException - if after is null
        See Also:
        compose(Function)
      • identity

        static <T> Function<T,​T> identity()
        Returns a function that always returns its input argument.
        Type Parameters:
        T - the type of the input and output objects to the function
        Returns:
        a function that always returns its input argument