code: public ResourceSection loadResourceSection() throws IOException {
          Optional<ResourceSection> rsrc = maybeLoadResourceSection();
          return (ResourceSection) getOrThrow(rsrc,
                  "unable to load resource section");
      }
docs: Loads all bytes and information of the resource section.
  
  The file on disk is read to fetch the information.
  
  @return {@link ResourceSection} of the given file
  @throws IOException
  if unable to read the file
  @throws IllegalStateException
  if section can not be loaded