String initialString = IoTestCase.ASCII + IoTestCase.I18N;
    return new FileByteSinkFactory(initialString.getBytes(UTF_8));
  }

  public static CharSourceFactory fileCharSourceFactory() {
    return new FileCharSourceFactory();
  }

  public static CharSinkFactory fileCharSinkFactory() {
    return new FileCharSinkFactory(null);
  }

  public static CharSinkFactory appendingFileCharSinkFactory() {