@HiveDecimalWritableVersionV2
  public void setFromBigIntegerBytesAndScale(
      byte[] bigIntegerBytes, int offset, int length, int scale) {
    fastReset();
    isSet = fastSetFromBigIntegerBytesAndScale(bigIntegerBytes, offset, length, scale);
    if (!isSet) {
      fastReset();
    }
  }
Set the writable's current value to the signed value from BigInteger bytes and a specified
scale.
<p>
Afterwards, the isSet() method will return true, unless conversion failed.
storage-api/src/java/org/apache/hadoop/hive/serde2/io/HiveDecimalWritable.java