UIDateString

    public static String getUIDateString(LocalDate d){
        // Do not allow dates with negative years
        if(d.getYear() < 0){
            throw new UnsupportedOperationException("LocalDate has negative year value.");
        } else {
            DateTimeFormatter dtf = DateTimeFormat.forPattern(UI_DATE_FORMAT);
            return dtf.print(d);
        }
    }