@Override
        public FileVisitResult visitFile(Path f, BasicFileAttributes attrs) throws IOException {
          try {
            Files.delete(f);
          }
          catch (AccessDeniedException e) {
            if (!f.toFile().delete()) { // fallback
              throw e;
            }
          }
          deletedPaths.add(FileUtilRt.toSystemIndependentName(f.toString()));
          return FileVisitResult.CONTINUE;
        }
@Override
        public FileVisitResult visitFile(Path f, BasicFileAttributes attrs)