private void logException(HttpServletRequest request, ValidationException exception) {
        LOGGER.error(
                "Error {} url: '{}'",
                exception.getClass().getSimpleName(),
                request.getRequestURI(),
                exception);
    }
This class converts Hibernate {@link ValidationException} into http response.
rest/src/main/java/com/netflix/conductor/rest/controllers/ValidationExceptionMapper.java