@Override
  protected void tearDown() {
    for (File file : filesToDelete) {
      if (file.exists()) {
        delete(file);
      }
    }
    filesToDelete.clear();
  }

  private File getTestDir() throws IOException {
    if (testDir != null) {
      return testDir;
    }

    URL testFileUrl = IoTestCase.class.getResource("testdata/i18n.txt");
    if (testFileUrl == null) {