code: @Override
      public FileItem file(String name) {
          for (FileItem item : request.getFiles()) {
              // FileItem that do not have an real file attached, should not be returned
              if (item.field().equals(name) && !Strings.isNullOrEmpty(item.name())) {
                  return item;
              }
          }
          return null;
      }
docs: Gets the uploaded file having a form's field matching the given name.
  
  @param name the name of the field of the form that have uploaded the file
  @return the file object, {@literal null} if there are no file with this name