The ifPresentOrElse(java.util.function.DoubleConsumer, java.lang.Runnable) method helps us to perform the specified DoubleConsumer action the value of this OptionalDouble object. If a value is not present in this OptionalDouble, then this method performs the given empty-based Runnable emptyAction, passed as the second parameter
Syntax:
public void ifPresentOrElse(DoubleConsumer action, Runnable emptyAction)
Parameters: This method accepts two parameters:
- action: which is the action to be performed on this Optional, if a value is present.
- emptyAction: which is the empty-based action to be performed, if no value is present.
Return value: This method returns nothing.
Exception: This method throw NullPointerException if a value is present and the given action is null, or no value is present and the given empty-based action is null.
Below programs illustrate ifPresentOrElse() method:
Program 1:
// Java program to demonstrate // OptionalDouble.ifPresentOrElse() method import java.util.OptionalDouble;
public class GFG {
public static void main(String[] args)
{
// create a OptionalDouble
OptionalDouble opdouble
= OptionalDouble.of( 234543.23453 );
// apply ifPresentOrElse
opdouble.ifPresentOrElse(
(value)
-> { System.out.println(
"Value is present, its: "
+ value); },
()
-> { System.out.println(
"Value is empty"); });
}
} |
Output:
Value is present, its: 12
Program 2:
// Java program to demonstrate // OptionalDouble.ifPresentOrElse method import java.util.OptionalDouble;
public class GFG {
public static void main(String[] args)
{
// create a OptionalDouble
OptionalDouble opdouble
= OptionalDouble.empty();
// apply ifPresentOrElse
opdouble.ifPresentOrElse(
(value)
-> { System.out.println(
"Value is present, its: "
+ value); },
()
-> { System.out.println(
"Value is empty"); });
}
} |
Output:
Value is empty