presto-accumulo/src/main/java/io/prestosql/plugin/accumulo/serializers/LexicoderRowSerializer.java/LexicoderRowSerializer/getMap
class LexicoderRowSerializer:    @Override
    public Block getMap(String name, Type type)
    {
        return AccumuloRowSerializer.getBlockFromMap(type, decode(type, getFieldValue(name)));
    }