code: private static <T> T executeCommand(final String database, final BsonDocument command,
                                          final FieldNameValidator fieldNameValidator, final Decoder<T> decoder,
                                          final ConnectionSource source, final Connection connection,
                                          final ReadPreference readPreference) {
          return executeCommand(database, command, fieldNameValidator, decoder, source, connection,
                  readPreference, new IdentityReadTransformer<T>(), source.getSessionContext());
      }
docs: /* Private Read Connection Source Helpers