getLocalDatabase method Null safety

Implementation

static Future<LocalDatabase> getLocalDatabase() async {
  await Hive.initFlutter();
  final LocalDatabase localDatabase = LocalDatabase._();
  final List<AbstractDao> daos = <AbstractDao>[
    DaoProduct(localDatabase),
    DaoProductList(localDatabase),
    DaoStringList(localDatabase),
    DaoString(localDatabase),
    DaoInt(localDatabase),
    DaoStringListMap(localDatabase),
  ];
  for (final AbstractDao dao in daos) {
    dao.registerAdapter();
  }
  for (final AbstractDao dao in daos) {
    await dao.init();
  }
  return localDatabase;
}