Interface UnaryOperator<T>

Type Parameters:: T - the type of the operand and result of the operator

All Superinterfaces:: Function<T,T>

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 UnaryOperator<T> extends Function<T,T>

Represents an operation on a single operand that produces a result of the same type as its operand. This is a specialization of Function for the case where the operand and result are of the same type.

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

Since:

1.8

See Also:

Method Summary

Modifier and Type	Method	Description
`static <T> UnaryOperator<T>`	`identity()`	Returns a unary operator that always returns its input argument.

Methods declared in interface Function

andThen, apply, compose

Modifier and Type	Method	Description
`default <V> Function<T,V>`	`andThen(Function<? super T, ? extends V> after)`	Returns a composed function that first applies this function to its input, and then applies the `after` function to the result.
`T`	`apply(T t)`	Applies this function to the given argument.
`default <V> Function<V,T>`	`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.

Method Details

identity

static <T> UnaryOperator<T> identity()

Returns a unary operator that always returns its input argument.

Type Parameters:: T - the type of the input and output of the operator
Returns:: a unary operator that always returns its input argument

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