Java tutorial
import java.util.InputMismatchException; import java.util.Scanner; public class Test { public static void main(String[] args) { try { System.out.print("Enter a number: "); int number = new Scanner(System.in).nextInt(); if (number < 0) { throw new InvalidParameter(); } System.out.println("The number is: " + number); } catch (InputMismatchException | InvalidParameter e) { System.out.println("Invalid input, try again"); } } } class InvalidParameter extends java.lang.Exception { public InvalidParameter() { super("Invalid Parameter"); } }