OptionalDouble isPresent() method in Java with examples

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());
    }
}

Output:

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");
    }
}

Output:

Value absent

References: https://docs.oracle.com/javase/10/docs/api/java/util/OptionalDouble.html#isPresent()