private List<AclEntry> getAclEntries(AclType aclType, Set<String> users) {
      List<AclEntry> aclEntries = new ArrayList<>();
      switch (aclType) {
        case ACCESS:
          for (String user : users) {
            aclEntries.add(aclEntry(ACCESS, user));
          }
          break;
        case DEFAULT:
          for (String user : users) {
            aclEntries.add(aclEntry(DEFAULT, user));
          }
          break;
        case DEFAULT_ADN_ACCESS:
          for (String user : users) {
            aclEntries.add(aclEntry(ACCESS, user));
            aclEntries.add(aclEntry(DEFAULT, user));
          }
          break;
        default:
          throw new IllegalArgumentException("Illegal HDFS acl type: " + aclType);
      }
      return aclEntries;
    }
Inner class used to describe modify or remove what type of acl entries(ACCESS, DEFAULT,
ACCESS_AND_DEFAULT) for files or directories(and child files).
hbase-server/src/main/java/org/apache/hadoop/hbase/security/access/SnapshotScannerHDFSAclHelper.java