private static void printHelp(Options opt) {
    new HelpFormatter().printHelp(
      "RegionPlacement < -w | -u | -n | -v | -t | -h | -overwrite -r regionName -f favoredNodes "
        + "-diff>" + " [-l false] [-m false] [-d] [-tables t1,t2,...tn] [-zk zk1,zk2,zk3]"
        + " [-fs hdfs://a.b.c.d:9000] [-hbase_root /HBASE]",
      opt);
  }
A tool that is used for manipulating and viewing favored nodes information for regions. Run with
-h to get a list of the options
hbase-server/src/main/java/org/apache/hadoop/hbase/master/RegionPlacementMaintainer.java