@Override
  public AggregatedAccountStorageStats queryAggregatedAccountStorageStatsByClusterName(String clusterName)
      throws Exception {
    if (clusterName.equals(this.clusterName)) {
      return aggregatedAccountStats;
    } else {
      return null;
    }
  }
Constructor to instantiate an {@link InmemoryAccountStatsStore}.
@param clusterName the clusterName
@param hostname the hostname
ambry-mysql/src/main/java/com/github/ambry/accountstats/InmemoryAccountStatsStore.java