net.ashwork.functionality

Interface Function0<R>

Type Parameters:

R - the type of the result of the function

All Superinterfaces:

Arity, FunctionN<R>, ResultChainable<R>, ResultChainableResult<R>, Variant<java.util.function.Supplier<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 Function0<R>
extends FunctionN<R>, Variant<java.util.function.Supplier<R>>

Represents a function that accepts no arguments and produces a result. This is the zero-arity specialization of FunctionN.

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

Since:

3.0.0

See Also:

FunctionN

Nested Class Summary

Nested classes/interfaces inherited from interface net.ashwork.functionality.FunctionN

FunctionN.FunctionSizeException, FunctionN.Instance<R>

Method Summary

Modifier and Type	Method and Description
default <V> Function0<V>	andThen(Function1<? super R,? extends V> after) Returns a chained object that applies this chainable object, and then applies the after function to ths result.
default <V> Function0<V>	andThenUnchecked(Function1<? super R,? extends V> after) Returns a chained object that applies this chainable object, and then applies the after function to ths result.
R	apply() Applies this function.
default R	applyAllUnchecked(java.lang.Object... args) Applies this function to the given arguments.
default int	arity() Returns the number of arguments of the function.
static <R> Function0<R>	fromVariant(java.util.function.Supplier<? extends R> supplier) Creates an instance of this object from its Supplier variant.
default java.util.function.Supplier<R>	toVariant() Returns the variant of this object.

Methods inherited from interface net.ashwork.functionality.FunctionN

checkSize, checkSize, sizedApplyAllUnchecked

Method Detail

apply

R apply()

Applies this function.

Returns:

the function result

applyAllUnchecked

default R applyAllUnchecked(java.lang.Object... args)

Description copied from interface: FunctionN

Applies this function to the given arguments. Makes no assumptions of the arguments passed in and whether a value will compute successfully.

Specified by:

applyAllUnchecked in interface FunctionN<R>

Parameters:

args - the function arguments

Returns:

the function result

arity

default int arity()

Description copied from interface: FunctionN

Returns the number of arguments of the function. If used as a functional interface with a non-specific number of arguments, this will return -1.

Specified by:

arity in interface Arity

Specified by:

arity in interface FunctionN<R>

Returns:

the number of arguments of the function

fromVariant

static <R> Function0<R> fromVariant(java.util.function.Supplier<? extends R> supplier)

Creates an instance of this object from its Supplier variant.

Type Parameters:

R - the type of the result of the function

Parameters:

supplier - the variant of this object

Returns:

an instance of this object

See Also:

Supplier

toVariant

default java.util.function.Supplier<R> toVariant()

Description copied from interface: Variant

Returns the variant of this object.

Specified by:

toVariant in interface Variant<java.util.function.Supplier<R>>

Returns:

the variant of this object

See Also:

Supplier

andThen

default <V> Function0<V> andThen(Function1<? super R,? extends V> after)

Description copied from interface: ResultChainable

Returns a chained object that applies this chainable object, and then applies the after function to ths result. If evaluation of either throws an exception, it is relayed to the caller of the chained object.

Specified by:

andThen in interface FunctionN<R>

Specified by:

andThen in interface ResultChainable<R>

Specified by:

andThen in interface ResultChainableResult<R>

Type Parameters:

V - the type of the output of the after function, and of the chained object

Parameters:

after - the function to apply after this chainable object is applied

Returns:

a chained object that applies this chainable object and then applies the after function

andThenUnchecked

default <V> Function0<V> andThenUnchecked(Function1<? super R,? extends V> after)

Description copied from interface: ResultChainable

Returns a chained object that applies this chainable object, and then applies the after function to ths result. If evaluation of either throws an exception, it is relayed to the caller of the chained object. This makes no assumptions on the arguments of this method.

Specified by:

andThenUnchecked in interface FunctionN<R>

Specified by:

andThenUnchecked in interface ResultChainable<R>

Specified by:

andThenUnchecked in interface ResultChainableResult<R>

Type Parameters:

V - the type of the output of the after function, and of the chained object

Parameters:

after - the function to apply after this chainable object is applied

Returns:

a chained object that applies this chainable object and then applies the after function