presto-spi/src/main/java/io/prestosql/spi/block/ByteArrayBlock.java/ByteArrayBlock/getByte
class ByteArrayBlock:    @Override
    public byte getByte(int position, int offset)
    {
        checkReadablePosition(position);
        if (offset != 0) {
            throw new IllegalArgumentException("offset must be zero");
        }
        return values[position + arrayOffset];
    }