Exception handling with a do-while loop in Java

Question

The algorithm should take in 3 integers to an ArrayList. If the input is not an integer, then there should be a prompt. When I execute my code the catch clause is e

Answer 1

If inputNum = input.nextInt(); cannot be fit into an int and a InputMismatchException is raised, the input of the Scanner is not consumed.

So after the catch, it loops and it goes again here :

inputNum = input.nextInt();

with exactly the same content in the input.

So you should execute input.nextLine(); in the catch statement to discard the current input and allow a new input from the user.
Besides it makes more sense to catch InputMismatchException rather than Exception as other exception with no relation with a mismatch could occur and it would not be useful to display to the user "invalid number " if it is not the issue :

    catch (InputMismatchException e){
        System.out.println("invalid number ");
        input.nextLine();
    }