@Override public Sort resolveArgument(MethodParameter parameter, @Nullable ModelAndViewContainer mavContainer, NativeWebRequest webRequest, @Nullable WebDataBinderFactory binderFactory) { String[] directionParameter = webRequest.getParameterValues(getSortParameter(parameter)); // No parameter if (directionParameter == null) { return getDefaultFromAnnotationOrFallback(parameter); } // Single empty parameter, e.g "sort=" if (directionParameter.length == 1 && !StringUtils.hasText(directionParameter[0])) { return getDefaultFromAnnotationOrFallback(parameter); } return parseParameterIntoSort(directionParameter, propertyDelimiter); }