code: @Override
      public Iterable<PersonDocument> findAll(final RootDocument rootDocument) {
          if (rootDocument == null) {
              return Collections.emptyList();
          }
          final Iterable<PersonDocument> personDocuments =
                  findAll(rootDocument.getFilename());
          for (final PersonDocument personDocument : personDocuments) {
              final Person person = personDocument.getGedObject();
              person.setParent(rootDocument.getGedObject());
          }
          return personDocuments;
      }
docs: {@inheritDoc}