@Override
  public void postCreateNamespace(ObserverContext<MasterCoprocessorEnvironment> c,
    NamespaceDescriptor ns) throws IOException {
    if (checkInitialized("createNamespace " + ns.getName())) {
      // Create namespace directories to make HDFS acls can be inherited
      List<Path> paths = hdfsAclHelper.getNamespaceRootPaths(ns.getName());
      for (Path path : paths) {
        hdfsAclHelper.createDirIfNotExist(path);
      }
    }
  }
Provider for mapping principal names to Users
hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/SnapshotScannerHDFSAclController.java