@Service
class MyEntityService {
    MyEntityRepository myEntityRepository; // extends PagingAndSortingRepository<MyEntity, ObjectId>

    updateMultipleEntities(UpdateRules updateRules) {
        Criteria criteria = buildCriteria(updateRules);
        long totalrecords = myEntityRepository.count(criteria);
        long totalUpdateCound = 0;

        // LET US ASSUME THAT NUMBER OF RECORDS DOES NOT CHANGE

        while (totalUpdateCound < totalrecords) {
            Page page = myEntityRepository.findAll(buildPageble(totalUpdateCound, criteria));
            processElementsFromPage(page);
        }
    }
}

@Service
class MyEntityService {
    MyEntityRepository myEntityRepository; // extends CrudRepository<MyEntity, ObjectId>

    updateMultipleEntities(UpdateRules updateRules) {
        Criteria criteria = buildCriteria(updateRules);

        // LET US ASSUME THAT NUMBER OF RECORDS DOES NOT CHANGE
        myEntityRepository.streamAll(criteria).forEach(element -> processElement(element, updateRules));

    }
}