public static SpaceQuotaSnapshot getCurrentSnapshotFromQuotaTable(Connection conn,
    TableName tableName) throws IOException {
    try (Table quotaTable = conn.getTable(QuotaTableUtil.QUOTA_TABLE_NAME)) {
      Map<TableName, SpaceQuotaSnapshot> snapshots = new HashMap<>(1);
      Result result = quotaTable.get(makeQuotaSnapshotGetForTable(tableName));
      // if we don't have any row corresponding to this get, return null
      if (result.isEmpty()) {
        return null;
      }
      // otherwise, extract quota snapshot in snapshots object
      extractQuotaSnapshot(result, snapshots);
      return snapshots.get(tableName);
    }
  }
Returns the current space quota snapshot of the given {@code tableName} from
{@code QuotaTableUtil.QUOTA_TABLE_NAME} or null if the no quota information is available for
that tableName.
@param conn      connection to re-use
@param tableName name of the table whose current snapshot is to be retreived
hbase-client/src/main/java/org/apache/hadoop/hbase/quotas/QuotaTableUtil.java