class DataMigrationRepository {

    public Map<String, Unit> getUnitGraphByIds(Collection<String> unitIds) {

        FindIterable<Unit> iterable = MetadataCollections.UNIT.getCollection()
            .find(in(Unit.ID, unitIds))
            .batchSize(unitIds.size())
            .projection(UNIT_VITAM_GRAPH_PROJECTION);

        Map<String, Unit> directParentById = new HashMap<>();
        try (MongoCursor<Unit> cursor = iterable.iterator()) {
            while (cursor.hasNext()) {
                Unit unit = cursor.next();
                directParentById.put(unit.getId(), unit);
            }
        }

        return directParentById;
    }

    public  DataMigrationRepository();
    @VisibleForTesting  DataMigrationRepository(int bulkSize);

}