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
// Java program to demonstrate// OptionalDouble.ifPresentOrElse() methodimport 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
// Java program to demonstrate// OptionalDouble.ifPresentOrElse methodimport 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
