Question

public void processing()
{

    System.out.println("Please enter the amount of saving per month: ");

    try
    {
        while(input.hasNext())
        {
            setSavingPermonth(input.nextDouble());

            System.out.println("Please enter expected interest rate: ");
            setInterestRate(input.nextDouble());

            System.out.println("Please enter number of month for saving: ");
            setNumberOfMonth(input.nextInt());

            displayInputs();
            System.out.println();
            totalContibution();
            totalSavingAmount();

            System.out.println();
            System.out.println("\nPlease enter the amount of saving per month: \n(or <Ctrl + D> to close the program)");
        }
    }
    catch(InputMismatchException inputMismatchException)
    {
        System.err.println("Input must be numeric. \ntry again: ");
              //**Anything need to done here in order to go back to setInterestRate()?**
    }
}

I want to go back to where before the exception caught the mis-input exception, for example, I type in a string for the setInterestRate(), but Java catches me there, and display the error message, question: how can I go back to there so that I can re-enter a correct data ?

Answer 1

Rewrite your code so it uses the following method:

static double inputDouble(Scanner input) {
  while (input.hasNext()) try {
    return input.nextDouble();
  }
  catch (InputMismatchException e) {
    System.out.println("Wrong input. Try again.");
    input.next(); // consume the invalid double
  }
  throw new IOException("Input stream closed");
}