The orElseThrow(Supplier) method of OptionalInt class used to get the value contained by OptionalInt. 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> int 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 // OptionalInt.orElseThrow(Supplier) method import java.util.OptionalInt; public class GFG { public static void main(String[] args) { // create a OptionalInt OptionalInt opint = OptionalInt.of( 24 ); // apply orElseThrow(Supplier) int value = opint.orElseThrow(ArithmeticException:: new ); System.out.println( "value " + value); } } |
Output:
Program 2:
// Java program to demonstrate // OptionalInt.orElseThrow(Supplier) method import java.io.IOException; import java.util.OptionalInt; public class GFG { public static void main(String[] args) { // create a OptionalInt OptionalInt opint = OptionalInt.empty(); // apply orElseThrow(Supplier) int value; try { value = opint.orElseThrow(IOException:: new ); } catch (IOException e) { System.out.println( "Exception " + e); } } } |
Output: