UnaryOperator (Java Platform SE 8 ) (original) (raw)

• 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
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:
Function

• • Method Summary

  All Methods Static Methods Default Methods

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

     * ### Methods inherited from interface java.util.function.[Function](../../../java/util/function/Function.html "interface in java.util.function")  
     `[andThen](../../../java/util/function/Function.html#andThen-java.util.function.Function-), [apply](../../../java/util/function/Function.html#apply-T-), [compose](../../../java/util/function/Function.html#compose-java.util.function.Function-)`

• • Method Detail

     * #### identity  
     static <T> [UnaryOperator](../../../java/util/function/UnaryOperator.html "interface in java.util.function")<T> identity()  
     Returns a unary operator that always returns its input argument.  
     Specified by:  
     `[identity](../../../java/util/function/Function.html#identity--)` in interface `[Function](../../../java/util/function/Function.html "interface in java.util.function")<[T](../../../java/util/function/UnaryOperator.html "type parameter in UnaryOperator"),[T](../../../java/util/function/UnaryOperator.html "type parameter in UnaryOperator")>`  
     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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