presto-redis/src/main/java/io/prestosql/plugin/redis/decoder/hash/HashRedisRowDecoderFactory.java/HashRedisRowDecoderFactory/chooseFieldDecoder
class HashRedisRowDecoderFactory:    private RedisFieldDecoder<String> chooseFieldDecoder(DecoderColumnHandle column)
    {
        checkArgument(!column.isInternal(), "unexpected internal column '%s'", column.getName());
        if (column.getDataFormat() == null) {
            return new HashRedisFieldDecoder();
        }
        if (column.getType().getJavaType() == long.class && "iso8601".equals(column.getDataFormat())) {
            return new ISO8601HashRedisFieldDecoder();
        }
        throw new IllegalArgumentException(format("unknown data format '%s' for column '%s'", column.getDataFormat(), column.getName()));
    }