class JFormRuleNumber extends JFormRule
{
    public function test(SimpleXMLElement $element, $value, $group = null, JRegistry $input = null, JForm $form = null)
    {
        // If the field is empty and not required, the field is valid.
        $required = ((string) $element['required'] == 'true' || (string) $element['required'] == 'required');

        if (!$required && empty($value))
        {
            return true;
        }

        $min   = isset($element['min']) ? (int)$element['min'] : null;
        $max   = isset($element['max']) ? (int)$element['max'] : null;

        if(!is_null($min) && $min > $value)
        {
            return false;
        }

        if(!is_null($max) && $max < $value)
        {
            return false;
        }

        return true;
    }
}