@Override
  public void close() {
    routingTableProvider.shutdown();
    try {
      if (helixManager.isConnected()) {
        helixManager.disconnect();
      }
    } finally {
      dataNodeConfigSource.close();
    }
  }
Construct a HelixDcInfo object with the given parameters.

@param dcName               the associated datacenter name.
@param dcZkInfo             the {@link ClusterMapUtils.DcZkInfo} associated with the DC.
@param helixManager         the associated {@link HelixManager} for this datacenter. This can be null if the
                            datacenter is not managed by helix.
@param clusterChangeHandler the associated {@link HelixClusterChangeHandler} for this datacenter.
@param dataNodeConfigSource the {@link DataNodeConfigSource} for this datacenter.
@param routingTableProvider a helix helper class to provide snapshot of the cluster.
ambry-clustermap/src/main/java/com/github/ambry/clustermap/HelixDcInfo.java