OptionalDouble hashCode() method in Java with examples

The hashCode() method help us to get the hash code of the value, if Double value is present, otherwise 0 (zero) if no Double value is present in OptionalDouble object. Syntax:

public int hashCode()

Parameters: This method does not accepts any parameter. Return value: This method returns hash code value of the present value or 0 if no value is present. Below programs illustrate hashCode() method: Program 1:

Java

// Java program to demonstrate
// OptionalDouble.hashCode() method

import java.util.OptionalDouble;

public class GFG {

    public static void main(String[] args)
    {

        // create a OptionalDouble instance
        OptionalDouble opDouble
            = OptionalDouble.of(253255.432525);

        System.out.println("OptionalDouble: "
                           + opDouble.toString());

        // get hashCode value using hashCode()
        System.out.println("HashCode value: "
                           + opDouble.hashCode());
    }
}

Output:

OptionalDouble: OptionalDouble[253255.432525]
HashCode value: 885080309

Program 2:

Java

// Java program to demonstrate
// OptionalDouble.hashCode() method

import java.util.OptionalDouble;

public class GFG {

    public static void main(String[] args)
    {

        // create a OptionalDouble instance
        OptionalDouble opDouble
            = OptionalDouble.empty();

        System.out.println("OptionalDouble: "
                           + opDouble.toString());

        // get hashCode value using hashCode()
        System.out.println("HashCode value: "
                           + opDouble.hashCode());
    }
}

Output:

OptionalDouble: OptionalDouble.empty
HashCode value: 0

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