code: @Override
      public final FamilyDocument findByFileAndString(final String filename,
              final String string) {
          final Query searchQuery = new Query(Criteria.where("string").is(string)
                  .and("filename").is(filename));
          final FamilyDocumentMongo familyDocument =
                  mongoTemplate.findOne(searchQuery, FamilyDocumentMongo.class);
          if (familyDocument == null) {
              return null;
          }
          final Family family =
                  (Family) toObjConverter.createGedObject(null, familyDocument);
          familyDocument.setGedObject(family);
          return familyDocument;
      }
docs: {@inheritDoc}