protected AbstractValidationRule createValidationRule(Element element) {
String expression = element.getAttribute(CONDITION_ATTR);
if (!StringUtils.hasText(expression)) {
throw new ValidationConfigurationException("Element '" + ELEMENT_NAME + "' must have a '" + CONDITION_ATTR + "' attribute");
}
return new ExpressionValidationRule(getConditionExpressionParser(), expression);
}