2.5.  Develop code that uses the UnaryOperator interface

[Note]

The java.util.function.UnaryOperator is a Java 8 functional interface that extends java.util.function.Function:


package java.util.function;

@FunctionalInterface
public interface UnaryOperator<T extends Object> extends Function<T, T> {

    ...

}

					

The UnaryOperator is used to work on a single operand and it returns the same type as an operand. UnaryOperator can be used as lambda expression to pass as an argument. While defining UnaryOperator, we need to define T apply(T t) method inherited from java.util.function.Function.


UnaryOperator<String> uo = s -> s + " is great !";
System.out.print(uo.apply("Java 8"));

					

output:

Java 8 is great !
					

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