Indhumathi,
BigInteger provides the values as a two's-complement big endian byte array
when toByteArray is called. It also accepts byte arrays with that format in
its constructor. See
https://docs.oracle.com/javase/7/docs/api/java/math/BigInteger.html#toByteArray()
The conversion you're looking at is for bytes, so this also doesn't need to
pad the values to a certain length. If you want to see how that is done,
look at the fixed conversion.
rb
On Tue, Sep 4, 2018 at 8:55 AM Indhumathi M <indhumathi...@gmail.com> wrote:
> Hello all,
> I am working on avro logical type decimal, but was not sure what data has
> to be provided.
> As mentioned in the Avro document,
> A decimal logical type annotates Avro bytes or fixed types. The byte array
> must contain the two's-complement representation of the unscaled integer
> value in big-endian byte order. The scale is fixed, and is specified using
> an attribute.
>
> But in code, in Conversions class, I can see that, from a decimal value, it
> is forming a ByteArray.
>
> @Override
> public BigDecimal fromBytes(ByteBuffer value, Schema schema, LogicalType
> type) {
> int scale = ((LogicalTypes.Decimal) type).getScale();
> // always copy the bytes out because BigInteger has no offset/length ctor
> byte[] bytes = value.get(new byte[value.remaining()]).array();
> return new BigDecimal(new BigInteger(bytes), scale);
> }
>
> @Override
> public ByteBuffer toBytes(BigDecimal value, Schema schema, LogicalType
> type) {
> int scale = ((LogicalTypes.Decimal) type).getScale();
> if (scale != value.scale()) {
> throw new AvroTypeException("Cannot encode decimal with scale " +
> value.scale() + " as scale " + scale);
> }
> return ByteBuffer.wrap(value.unscaledValue().toByteArray());
> }
>
> but, I find that, nowhere two's-complement representation of the
> unscaled integer
> value in big-endian byte order is stored in byte array.
>
> Can anyone help me with this?
>
> Thanks,
>
> Indhumathi M
>
--
Ryan Blue
Software Engineer
Netflix
