code: public List<ACLHolder> getACLHolders() throws RepositoryException
     {
        WorkspaceStorageConnection conn = dataContainer.openConnection();
        try
        {
           return conn.getACLHolders();
        }
        finally
        {
           conn.close();
        }
     }
docs: Gets the list of all the ACL holders
  @throws RepositoryException if an error occurs