public static void cleanDirectory(File directory) throws IOException {
    requireNonNull(directory, DIRECTORY_CAN_NOT_BE_NULL);
    if (!directory.exists()) {
      return;
    }

    cleanDirectoryImpl(directory.toPath());
  }
@Test
  public void cleanDirectory_does_nothing_if_argument_does_not_exist() throws IOException {
    FileUtils2.cleanDirectory(new File("/a/b/ToDoSSS"));
  }