docs: protected Set<Resource> doFindPathMatchingFileResources(Resource rootDirResource, String subPattern)
          throws IOException {
  
          File rootDir;
          try {
              rootDir = rootDirResource.getFile().getAbsoluteFile();
          } catch (IOException ex) {
              return Collections.emptySet();
          }
          return doFindMatchingFileSystemResources(rootDir, subPattern);
      }