[jira] Updated: (LUCENE-1522) another highlighter

> another highlighter
> -------------------
>
>                 Key: LUCENE-1522
>                 URL: https://issues.apache.org/jira/browse/LUCENE-1522
>             Project: Lucene - Java
>          Issue Type: Improvement
>          Components: contrib/highlighter
>            Reporter: Koji Sekiguchi
>            Priority: Minor
>         Attachments: LUCENE-1522.patch
>
>
> I've written this highlighter for my project to support bi-gram token stream. The idea was inherited from my previous project with my colleague and LUCENE-644. This approach needs highlight fields to be TermVector.WITH_POSITIONS_OFFSETS, but is fast and can support N-grams. This depends on LUCENE-1448 to get refined term offsets.
> usage:
> {code:java}
> Highlighter h = new Highlighter();
> FieldQuery fq = h.getFieldQuery( query );
> // docId=0, fieldName="content", fragCharSize=100, numFragments=3
> String[] fragments = h.getBestFragments( fq, reader, 0, "content", 100, 3 );
> {code}
> features:
> - fast for large docs
> - supports "fixed size" N-gram (e.g. (2,2), not (1,3)) (can solve LUCENE-1489)
> - supports PhraseQuery, phrase-unit highlighting with slops
> {noformat}
> q="w1 w2"
> <b>w1 w2</b>
> ---------------
> q="w1 w2"~1
> <b>w1</b> w3 <b>w2</b> w3 <b>w1 w2</b>
> {noformat}
> - highlight fields need to be TermVector.WITH_POSITIONS_OFFSETS
> - easy to apply patch due to independent package (contrib/highlighter2)
> - uses Java 1.5
> - looks query boost to score fragments (currently doesn't see idf, but it should be possible)
> - pluggable FragListBuilder
> - pluggable FragmentsBuilder
> to do:
> - term positions can be unnecessary when phraseHighlight==false
> - collects performance numbers