Interface ITermToBytesRefAttribute

This attribute is requested by TermsHashPerField to index the contents. This attribute can be used to customize the final byte[] encoding of terms.

Consumers of this attribute call BytesRef up-front, and then invoke FillBytesRef() for each term. Example:

  TermToBytesRefAttribute termAtt = tokenStream.GetAttribute<TermToBytesRefAttribute>;
  BytesRef bytes = termAtt.BytesRef;

  while (tokenStream.IncrementToken()
  {
    // you must call termAtt.FillBytesRef() before doing something with the bytes.
    // this encodes the term value (internally it might be a char[], etc) into the bytes.
    int hashCode = termAtt.FillBytesRef();

    if (IsInteresting(bytes))
    {
      // because the bytes are reused by the attribute (like CharTermAttribute's char[] buffer),
      // you should make a copy if you need persistent access to the bytes, otherwise they will
      // be rewritten across calls to IncrementToken()

      DoSomethingWith(new BytesRef(bytes));
    }
  }
  ...

@lucene.experimental this is a very expert API, please use CharTermAttribute and its implementation of this method for UTF-8 terms.