1. Description
2. Method Summary
3. Method Details
   1. apply(T)
   2. compose(Function)
   3. andThen(Function)
   4. identity()

• Method Summary

  All MethodsStatic MethodsInstance MethodsAbstract MethodsDefault Methods

  Modifier and Type

  Method

  Description

  default <V> Function<T,V>

  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.

  R

  apply(T t)

  Applies this function to the given argument.

  default <V> Function<V,R>

  compose(Function<? super V, ? extends T> before)

  Returns a composed function that first applies the before function to its input, and then applies this function to the result.

  static <T> Function<T,T>

  identity()

  Returns a function that always returns its input argument.

• Method Details

  • apply

    R apply(T t)

    Applies this function to the given argument.

    Parameters: t - the function argument Returns: the function result

  • compose

    default <V> Function<V,R> compose(Function<? super V, ? extends T> before)

    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 See Also:

    • andThen(Function)

  • andThen

    default <V> Function<T,V> 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

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