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What is the purpose of using Optional.ifPresentOrElse() method in Java 9?

JavaObject Oriented ProgrammingProgramming

The improvement of ifPresentOrElse() method in Optional class is that accepts two parameters, Consumer and Runnable. The purpose of of using ifPresentOrElse() method is that if an Optional contains a value, the function action is called on the contained value, i.e. action.accept (value), which is consistent with ifPresent() method. The difference from the ifPresent() method is that ifPresentOrElse() has a second parameter, emptyAction. If Optional contains no value, then ifPresentOrElse() method calls emptyAction, i.e. emptyAction.run().

Syntax

public void ifPresentOrElse(Consumer<? super T> action, Runnable emptyAction)

Example

import java.util.Optional;

public class IfPresentOrElseMethodTest {
   public static void main(String args[]) {
      Optional<Integer> optional = Optional.of(1);

      optional.ifPresentOrElse(x -> System.out.println("Value: " + x), () ->
                                    System.out.println("Not Present"));

      optional = Optional.empty();

      optional.ifPresentOrElse(x -> System.out.println("Value: " + x), () ->
                                    System.out.println("Not Present"));
   }
}

Output

Value: 1
Not Present
raja
raja
Updated on 25-Feb-2020 07:45:01

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