public List<String> getUserAuths(String user) {
    this.lock.readLock().lock();
    try {
      List<String> auths = EMPTY_LIST;
      Set<Integer> authOrdinals = getUserAuthsAsOrdinals(user);
      if (!authOrdinals.equals(EMPTY_SET)) {
        auths = new ArrayList<>(authOrdinals.size());
        for (Integer authOrdinal : authOrdinals) {
          auths.add(ordinalVsLabels.get(authOrdinal));
        }
      }
      return auths;
    } finally {
      this.lock.readLock().unlock();
    }
  }
Returns The total number of visibility labels.
hbase-server/src/main/java/org/apache/hadoop/hbase/security/visibility/VisibilityLabelsCache.java