public Set<Integer> getGroupAuthsAsOrdinals(String[] groups) {
    this.lock.readLock().lock();
    try {
      Set<Integer> authOrdinals = new HashSet<>();
      if (groups != null && groups.length > 0) {
        Set<Integer> groupAuthOrdinals = null;
        for (String group : groups) {
          groupAuthOrdinals = groupAuths.get(group);
          if (groupAuthOrdinals != null && !groupAuthOrdinals.isEmpty()) {
            authOrdinals.addAll(groupAuthOrdinals);
          }
        }
      }
      return (authOrdinals.isEmpty()) ? EMPTY_SET : authOrdinals;
    } finally {
      this.lock.readLock().unlock();
    }
  }
Returns the list of ordinals of labels associated with the groups
@return the list of ordinals
hbase-server/src/main/java/org/apache/hadoop/hbase/security/visibility/VisibilityLabelsCache.java