@Override
  public long getLong(int id) {
    if (isOpen()) {
      if (!type.isValidLongId(id)) {
        throw new IllegalArgumentException("Id, " + id + ", is not a long statistic.");
      }
      return _getLong(id);
    } else {
      return 0;
    }
  }
Gets the unique id for this resource
geode-core/src/main/java/org/apache/geode/internal/statistics/StatisticsImpl.java