@Override
  public Long getLong(String key) {
    return fetch(stats.getData(), key);
  }
@Test
  public void testGetLong() {
    for (String key : STATISTICS_KEYS) {
      final long expectedStat = getStatisticsValue(key);
      final long storageStat = storageStatistics.getLong(key);
      LOG.info("{}: FileSystem.Statistics={}, FileSystemStorageStatistics={}",
          key, expectedStat, storageStat);
      assertEquals(expectedStat, storageStat);
    }
  }