Why do I get InputMismatchException in this code?

I'm getting:
'Exception in thread "main" java.util.InputMismatchException' in:
float annualInterest = scanner.nextFloat();
I have tried double and now float, getting same error.
I put in a number with decimal (3.2) and getting this exception.
Someone can tell me whats wrong in this code?
Using JDK 14.

public class Main {

public static void main(String[] args) {
    final byte MONTHS_IN_YEAR = 12;
    final byte PERCENT = 100;

    Scanner scanner = new Scanner(System.in);

    System.out.print("Principal: ");
    int principal = scanner.nextInt();

    System.out.print("Annual Interest Rate: ");
    float annualInterest = scanner.nextFloat();
    float monthlyInterest = annualInterest / PERCENT / MONTHS_IN_YEAR;

    System.out.print("Period (Years): ");
    byte years = scanner.nextByte();
    int numberOfPayments = years * MONTHS_IN_YEAR;

    double mortgage = principal
                * (monthlyInterest * Math.pow(1 + monthlyInterest, numberOfPayments))
                / (Math.pow(1 + monthlyInterest, numberOfPayments) - 1);

    String mortgageFormatted = NumberFormat.getCurrencyInstance().format(mortgage);
    System.out.println("Mortgage: " + mortgageFormatted);
    }
}

> On my Mac, when it comes to "Annual Interest Rate: " and I write in 3.2, it crashes, but if i write in 3,2 then it works.

This is due to your system settings that determine the punctuation used for writing decimal numbers. We call this a "locale" in Java. One solution is to change the system settings, but this will change the settings for every program on your computer. For now, I suggest you just enter numbers using the format that your system accepts by default.

If you want to use different settings just in your own Java program, then you need to set the locale that corresponds to the rules you want to use. Don't fight it. In the future when you know more about Java, you can start learning about locale and how to set them in your Java code.

As the documentation of the Method says

> @throws InputMismatchException if the next token does not match the <i>Float</i> regular expression, or is out of range

I guess your Input (3.2) does not match the format of a float for your current locale. With my default locale (Locale.GERMAN) I would need to type "3,2".

If you want to change the Locale your Scanner uses internally you can do so by using Scanner.useLocale.