public static void cleanDirectory(File directory) throws IOException {
    requireNonNull(directory, DIRECTORY_CAN_NOT_BE_NULL);

    Path path = directory.toPath();
    if (!path.toFile().exists()) {
      return;
    }

    cleanDirectoryImpl(path);
  }
@Test
  public void cleanDirectory_does_nothing_if_argument_does_not_exist() throws IOException {
    FileUtils.cleanDirectory(new File("/a/b/ToDoSSS"));
  }