to.etc.function

Interface FunctionEx<T,R>

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 FunctionEx<T,R>

Author:

Frits Jalvingh Created on 12-1-17.

Method Summary

Modifier and Type	Method and Description
default <V> FunctionEx<T,V>	andThen(FunctionEx<? super R,? extends V> after)
R	apply(T t) Applies this function to the given argument.
default <V> FunctionEx<V,R>	compose(FunctionEx<? 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> FunctionEx<T,T>	identity() Returns a function that always returns its input argument.

Method Detail

apply

R apply(T t)
 throws Exception

Applies this function to the given argument.

Parameters:

t - the function argument

Returns:

the function result

Throws:

Exception

compose

default <V> FunctionEx<V,R> compose(@Nonnull
                                    FunctionEx<? super V,? extends T> before)
                             throws Exception

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

Exception

See Also:

andThen(FunctionEx)

andThen

default <V> FunctionEx<T,V> andThen(FunctionEx<? super R,? extends V> after)

identity

static <T> FunctionEx<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