Package org.apache.commons.io.function

Interface IOFunction<T,R>

Type Parameters:

T - the type of the input to the operations.

R - the return type of the operations.

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 IOFunction<T,R>

Like Function but throws IOException.

Since:

2.7

Method Summary

Modifier and Type	Method	Description
default IOConsumer<T>	andThen(java.util.function.Consumer<? super R> after)	Returns a composed IOFunction that first applies this function to its input, and then applies the after consumer to the result.
default <V> IOFunction<T,V>	andThen(java.util.function.Function<? super R,? extends V> after)	Returns a composed IOFunction that first applies this function to its input, and then applies the after function to the result.
default IOConsumer<T>	andThen(IOConsumer<? super R> after)	Returns a composed IOFunction that first applies this function to its input, and then applies the after consumer to the result.
default <V> IOFunction<T,V>	andThen(IOFunction<? super R,? extends V> after)	Returns a composed IOFunction 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> IOFunction<V,R>	compose(java.util.function.Function<? super V,? extends T> before)	Returns a composed IOFunction that first applies the before function to its input, and then applies this function to the result.
default IOSupplier<R>	compose(java.util.function.Supplier<? extends T> before)	Returns a composed IOFunction that first applies the before function to its input, and then applies this function to the result.
default <V> IOFunction<V,R>	compose(IOFunction<? super V,? extends T> before)	Returns a composed IOFunction that first applies the before function to its input, and then applies this function to the result.
default IOSupplier<R>	compose(IOSupplier<? extends T> before)	Returns a composed IOFunction that first applies the before function to its input, and then applies this function to the result.
static <T> IOFunction<T,T>	identity()	Returns a IOFunction that always returns its input argument.

Method Detail

apply

R apply(T t)
 throws java.io.IOException

Applies this function to the given argument.

Parameters:

t - the function argument

Returns:

the function result

Throws:

java.io.IOException - if the function throws an IOException

compose

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

Returns a composed IOFunction 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(IOFunction)

compose

default <V> IOFunction<V,R> compose(java.util.function.Function<? super V,? extends T> before)

Returns a composed IOFunction 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(IOFunction)

compose

default IOSupplier<R> compose(IOSupplier<? extends T> before)

Returns a composed IOFunction 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.

Parameters:

before - the supplier which feeds the application of this function

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(IOFunction)

compose

default IOSupplier<R> compose(java.util.function.Supplier<? extends T> before)

Returns a composed IOFunction 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.

Parameters:

before - the supplier which feeds the application of this function

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(IOFunction)

andThen

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

Returns a composed IOFunction 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(IOFunction)

andThen

default <V> IOFunction<T,V> andThen(java.util.function.Function<? super R,? extends V> after)

Returns a composed IOFunction 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(IOFunction)

andThen

default IOConsumer<T> andThen(IOConsumer<? super R> after)

Returns a composed IOFunction that first applies this function to its input, and then applies the after consumer to the result. If evaluation of either function throws an exception, it is relayed to the caller of the composed function.

Parameters:

after - the consumer to apply after this function is applied

Returns:

a composed function that first applies this function and then applies the after consumer

Throws:

java.lang.NullPointerException - if after is null

See Also:

compose(IOFunction)

andThen

default IOConsumer<T> andThen(java.util.function.Consumer<? super R> after)

Returns a composed IOFunction that first applies this function to its input, and then applies the after consumer to the result. If evaluation of either function throws an exception, it is relayed to the caller of the composed function.

Parameters:

after - the consumer to apply after this function is applied

Returns:

a composed function that first applies this function and then applies the after consumer

Throws:

java.lang.NullPointerException - if after is null

See Also:

compose(IOFunction)

identity

static <T> IOFunction<T,T> identity()

Returns a IOFunction 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