In Java, the OptionalInt object is a container object
which may or may not contain an integer value.
The OptionalInt class is present in the java.util package.
isPresent() methodThe isPresent() method is used to check if the OptionalInt object contains a value.
public boolean isPresent()
This method doesn’t take an argument.
This method returns true if the OptionalInt object contains a integer value. Otherwise, false will be returned.
The code below denotes how to use the isPresent method.
import java.util.OptionalInt;class OptionalIntIsPresentExample {public static void main(String[] args) {OptionalInt optional1 = OptionalInt.empty();OptionalInt optional2 = OptionalInt.of(1);System.out.println("Checking if optional1 has value : " + optional1.isPresent());System.out.println("Checking if optional2 has value : " + optional2.isPresent());}}
In the code above:
Line 1: We imported the OptionalInt class.
import java.util.OptionalInt;
Line 5: We used the empty method to get an empty OptionalInt object. The returned object doesn’t have any value.
OptionalInt optional1 = OptionalInt.empty();
Line 6: We used the of method to get an OptionalInt object with value 1.
OptionalInt optional2 = OptionalInt.of(1);
Line 7: We called the isPresent method on the optional1 object. This object doesn’t have any value, so false will be returned.
optional1.isPresent();//false
Line 8: We called the isPresent method on the optional2 object. This object has 1 as the value, so true will be returned.
optional2.isPresent();//true