@Override
    public String calculatePattern() {
        if (isTimeOnly()) {
            return calculateTimeOnlyPattern();
        }
        else if (isShowTime()) {
            return calculateWidgetPattern() + " " + calculateTimeOnlyPattern();
        }
        return calculateWidgetPattern();
    }
Standard 576px considered a small screen so we can auto switch the picker to touch mode
primefaces/src/main/java/org/primefaces/component/datepicker/DatePickerBase.java