public void markRegionAsSplit(final RegionInfo parent, final ServerName serverName,
final RegionInfo daughterA, final RegionInfo daughterB) throws IOException {
final RegionStateNode node = regionStates.getOrCreateRegionStateNode(parent);
node.setState(State.SPLIT);
final RegionStateNode nodeA = regionStates.getOrCreateRegionStateNode(daughterA);
nodeA.setState(State.SPLITTING_NEW);
final RegionStateNode nodeB = regionStates.getOrCreateRegionStateNode(daughterB);
nodeB.setState(State.SPLITTING_NEW);
regionStateStore.splitRegion(parent, daughterA, daughterB, serverName);
if (shouldAssignFavoredNodes(parent)) {
List<ServerName> onlineServers = this.master.getServerManager().getOnlineServersList();
((FavoredNodesPromoter)getBalancer()).
generateFavoredNodesForDaughter(onlineServers, parent, daughterA, daughterB);
}
}