OptionalDouble help us to create an object which may or may not contain a Double value. The isPresent() method help us to get the answer that double value is present in OptionalDouble object or not. If a double value is present, returns true, otherwise false.
Syntax:
public boolean isPresent()
Parameters: This method accepts nothing.
Return value: This method returns true if a value is present, otherwise false
Below programs illustrate isPresent() method:
Program 1:
// Java program to demonstrate // OptionalDouble.isPresent() method import java.util.OptionalDouble; public class GFG { public static void main(String[] args) { // create a OptionalDouble OptionalDouble opDouble = OptionalDouble.of( 3148.1345 ); // get value using isPresent() System.out.println( "OptionalDouble" + " has a value= " + opDouble.isPresent()); } } |
OptionalDouble has a value= true
Program 2:
// Java program to demonstrate // OptionalDouble.isPresent() method import java.util.OptionalDouble; public class GFG { public static void main(String[] args) { // create a OptionalDouble OptionalDouble opDouble = OptionalDouble.empty(); // try to get that value is present or not boolean response = opDouble.isPresent(); if (response) System.out.println( "Value present" ); else System.out.println( "Value absent" ); } } |
Value absent
References: https://docs.oracle.com/javase/10/docs/api/java/util/OptionalDouble.html#isPresent()