The orElseThrow(Supplier) method of OptionalLong class is used to get the long value contained by OptionalLong. If a value is present, this method returns the value, otherwise, this method throws an exception produced by the exception supplying function. The exception Supplier function is passed as a parameter.
Syntax:
public <X extends Throwable> long
orElseThrow(Supplier<X> exceptionSupplier)
throws X extends Throwable
Parameters: This method accepts one parameter exceptionSupplier which is the supplying function that produces an exception to be thrown.
Return value: This method returns the value, if present.
Exception: This method throw following Exceptions:
- X – if no value is present.
- NullPointerException – if no value is present and the exception supplying function is null
- X extends Throwable
Below programs illustrate orElseThrow(Supplier) method:
Program 1:
// Java program to demonstrate// OptionalLong.orElseThrow(Supplier) method import java.util.OptionalLong; public class GFG { public static void main(String[] args) { // create a OptionalLong OptionalLong opLong = OptionalLong.of(894763545123L); // apply orElseThrow(Supplier) long value = opLong.orElseThrow(ArithmeticException::new); System.out.println("value " + value); }} |
Output:
Program 2:
// Java program to demonstrate// OptionalLong.orElseThrow(Supplier) method import java.io.IOException;import java.util.OptionalLong; public class GFG { public static void main(String[] args) { // create a OptionalLong OptionalLong opLong = OptionalLong.empty(); // apply orElseThrow(Supplier) Long value; try { value = opLong.orElseThrow(ArithmeticException::new); } catch (ArithmeticException e) { // TODO Auto-generated catch block System.out.println("Exception " + e); } }} |
Output:
