How to determine where to place the currency symbol when formatting a number?

currency-formatting, internationalization, java, localization

Solution

I found this question while searching for a way to determine whether the currency symbol should be placed at the start or end of a currency for a specific locale. For others who might be looking for something similar, I ended up creating the following class to test this:

public class Test {   

    private static Locale[] locales = Locale.getAvailableLocales();
    static double decimal = 789456123.098;

    public static void main(String[] args) {

        for(Locale locale : locales){
            DecimalFormat decimalFormatter = (DecimalFormat)NumberFormat.getInstance(locale);
            NumberFormat currencyFormatter = NumberFormat.getCurrencyInstance(locale);
            DecimalFormatSymbols symbols = decimalFormatter.getDecimalFormatSymbols();
            String currencySymbol = symbols.getCurrencySymbol();
            String formattedCurrency = currencyFormatter.format(decimal);
            System.out.print(formattedCurrency + ";" + locale.getDisplayCountry() + ";" + locale.getDisplayLanguage() );
            System.out.println(";" + currencySymbol + ";" + currencySymbolAtStart(currencySymbol, formattedCurrency, true));
        }

    }

    private static boolean currencySymbolAtStart(String currencySymbol, String formattedCurrency, boolean defaultAtStart){

        if(formattedCurrency.startsWith(currencySymbol)){
            return true;
        }else if(formattedCurrency.endsWith(currencySymbol)){
            return false;
        }else{
            return defaultAtStart;
        }
    }

}

Pasting the results into a spreadsheet looks something like this:

There is one caveat here to be aware of. For languages that are read right to left, the currency symbol might appear on the right in the formatted text, yet technically, since you are reading from right to left, the currency still "starts with" the currency symbol, hence the result will return "true". See Egypt-Arabic in the screen snip above...

Problem

Original source