private static void collectJavadocRoots(VirtualFile file, final List<? super VirtualFile> result, final ProgressIndicator progressIndicator) {
      VfsUtilCore.visitChildrenRecursively(file, new VirtualFileVisitor<Void>() {
        @Override
        public boolean visitFile(@NotNull VirtualFile file) {
          progressIndicator.checkCanceled();
          //noinspection SpellCheckingInspection
          if (file.isDirectory() && file.findChild("allclasses-frame.html") != null && file.findChild("allclasses-noframe.html") != null) {
            result.add(file);
            return false;
          }
          return true;
        }
      });
    }
private static void collectJavadocRoots(VirtualFile file, final List<? super VirtualFile> result, final ProgressIndicator progressIndicator)