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) methodimport 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) methodimport 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:
