OptionalDouble help us to create an object which may or may not contain a Double value. The orElseThrow() method help us to get the double value. If double value is not present then this method will throw NoSuchElemenrException.
Syntax:
public Double orElseThrow()
Parameters: This method accepts nothing.
Return value: This method returns the Double value described by this OptionalDouble.
Exception: This method throws NoSuchElementException if no value is present
Below programs illustrate orElseThrow() method:
Program 1:
// Java program to demonstrate // OptionalDouble.orElseThrow() method import java.util.OptionalDouble; public class GFG { public static void main(String[] args) { // create a OptionalDouble OptionalDouble opDouble = OptionalDouble.of( 134.1 ); // get value using orElseThrow() System.out.println( "double Value extracted using" + " orElseThrow() = " + opDouble.orElseThrow()); } } |
Output:
double Value extracted using orElseThrow() = 134.1
Program 2:
// Java program to demonstrate // OptionalDouble.orElseThrow() method import java.util.OptionalDouble; public class GFG { public static void main(String[] args) { // create a OptionalDouble OptionalDouble opDouble = OptionalDouble.empty(); try { // try to get value from empty OptionalDouble Double value = opDouble.orElseThrow(); } catch (Exception e) { 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/OptionalDouble.html#orElseThrow()
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