BalanceAction batchMovesAndResetClusterState(BalancerClusterState cluster,
    List<MoveRegionAction> moves) {
    if (moves.isEmpty()) {
      return BalanceAction.NULL_ACTION;
    }
    MoveBatchAction batchAction = new MoveBatchAction(moves);
    undoBatchAction(cluster, batchAction);
    return batchAction;
  }
Generates a balancing action to appease the conditional.
@param cluster    Current state of the cluster.
@param isWeighing Flag indicating if the generator is being used for weighing.
@return A BalanceAction, or NULL_ACTION if no action is needed.
hbase-balancer/src/main/java/org/apache/hadoop/hbase/master/balancer/RegionPlanConditionalCandidateGenerator.java