OptionalLong help us to create an object which may or may not contain a Long value. The orElseThrow() method help us to get the value and if value is not present then this method will throw NoSuchElementException. Syntax:
public Long orElseThrow()
Parameters: This method accepts nothing. Return value: This method returns the Long value described by this OptionalLong. Exception: This method throws NoSuchElementException if no value is present Below programs illustrate orElseThrow() method: Program 1:Â
Java
// Java program to demonstrate// OptionalLong.orElseThrow() methodimport java.util.OptionalLong;Â
public class GFG {Â
    public static void main(String[] args)    {Â
        // create a OptionalLong        OptionalLong opLong = OptionalLong.of(45213246);Â
        // get value using orElseThrow()        System.out.println("Value extracted using"                           + " orElseThrow() = "                           + opLong.orElseThrow());    }} |
Output:
Value extracted using orElseThrow() = 45213246
Program 2:Â
Java
// Java program to demonstrate// OptionalLong.orElseThrow() methodÂ
import java.util.OptionalLong;Â
public class GFG {Â
    public static void main(String[] args)    {Â
        // create a OptionalLong        OptionalLong opLong = OptionalLong.empty();Â
        try {Â
            // try to get value from empty OptionalLong            long value = opLong.orElseThrow();        }        catch (Exception e) {Â
            System.out.println("Exception thrown : "                               + e);        }    }} |
Output:
Exception thrown : java.util.NoSuchElementException: No value present
References: https://docs.oracle.com/javase/10/docs/api/java/util/OptionalLong.html#orElseThrow()
