else if ("javax.servlet.http.Part".equals(parameter.getParameterType().getName())) {
arg = servletRequest.getPart(partName);
}
else {
try {
HttpInputMessage inputMessage = new RequestPartServletServerHttpRequest(servletRequest, partName);
arg = readWithMessageConverters(inputMessage, parameter, parameter.getParameterType());
WebDataBinder binder = binderFactory.createBinder(request, arg, partName);
if (arg != null) {
validate(binder, parameter);
}