@Override
  public void close() {
    // close the DataSource
    if (dataSource instanceof AutoCloseable) {
      try {
        ((AutoCloseable) dataSource).close();
      } catch (Exception e) {
        logger.error("Failed to close data source: ", e);
      }
    }
  }
Exposed for integration test usage.
@return the {@link Connection}.
ambry-mysql/src/main/java/com/github/ambry/repair/MysqlRepairRequestsDb.java