How to use

splitNodesWithRack

method

in

org.apache.hadoop.hdfs.server.blockmanagement.BlockPlacementPolicyDefault

@Override
public boolean isMovable(Collection<DatanodeInfo> locs,
  DatanodeInfo source, DatanodeInfo target) {
 final Map<String, List<DatanodeInfo>> rackMap = new HashMap<>();
 final List<DatanodeInfo> moreThanOne = new ArrayList<>();
 final List<DatanodeInfo> exactlyOne = new ArrayList<>();
 splitNodesWithRack(locs, locs, rackMap, moreThanOne, exactlyOne);
 return notReduceNumOfGroups(moreThanOne, source, target);
}

splitNodesWithRack(availableReplicas, delCandidates, rackMap, moreThanOne,
  exactlyOne);

splitNodesWithRack(candidates, rackMap, moreThanOne, exactlyOne);

splitNodesWithRack(candidates, rackMap, moreThanOne, exactlyOne);