presto-accumulo/src/main/java/io/prestosql/plugin/accumulo/io/AccumuloRecordSetProvider.java/AccumuloRecordSetProvider/AccumuloRecordSetProvider
class AccumuloRecordSetProvider:    @Inject
    public AccumuloRecordSetProvider(
            Connector connector,
            AccumuloConfig config)
    {
        this.connector = requireNonNull(connector, "connector is null");
        this.username = requireNonNull(config, "config is null").getUsername();
    }