io.micronaut.core.util.functional

Interface ThrowingFunction<T,R,E extends java.lang.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 exception that the function throws

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 ThrowingFunction<T,R,E extends java.lang.Throwable>

Represents a function that accepts one argument and produces a result.

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

Since:

1.1.0

Author:

James Kleeh

Method Summary

Modifier and Type	Method and Description
default <V> ThrowingFunction<T,V,E>	andThen(java.util.function.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> ThrowingFunction<V,R,E>	compose(java.util.function.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,E extends java.lang.Throwable> ThrowingFunction<T,T,E>	identity() Returns a function that always returns its input argument.

Method Detail

apply

R apply(T t)
 throws E extends java.lang.Throwable

Applies this function to the given argument.

Parameters:

t - the function argument

Returns:

the function result

Throws:

E - The exception to throw when something goes wrong

E extends java.lang.Throwable

compose

default <V> ThrowingFunction<V,R,E> compose(java.util.function.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:

java.lang.NullPointerException - if before is null

See Also:

andThen(Function)

andThen

default <V> ThrowingFunction<T,V,E> andThen(java.util.function.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:

java.lang.NullPointerException - if after is null

See Also:

compose(Function)

identity

static <T,E extends java.lang.Throwable> ThrowingFunction<T,T,E> identity()

Returns a function that always returns its input argument.

Type Parameters:

T - the type of the input and output objects to the function

E - the type of the exception the function throws

Returns:

a function that always returns its input argument