Dear,
I built my own scoring class by extending the DefaultSimilarity. Three major methods from DefaultSimilarity were overrided, including: 1. public float lengthNorm(FieldInvertState state) 2. public float tf(float freq) 3.public float idf(long docFreq, long numDocs) However, with embedded printing sentences (they are used to indicate which and when a method is called by printing messages to console), I found only tf() and idf() were called during a search process. The method lengthNorm(), which is really what I wanted to work on, was never called. I rolled back to Lucene350 and checked again. The DefaultSimilarity under Lucene 350 uses a computeNorm() method instead of lengthNorm(). And again, the overrided computeNorm() is never called either. I used explanation() to check the components of each score for a document. Besides the idf and tf scores, I did find a fieldNorm score, which has something to do with the document length. My questions are: 1. Why are the overrided lengthNorm() (under Lucene410) or computeNorm() (under Lucene350) methods not called during a searching process? 2. How and where is fieldNorm calculated? Thank you very much! Oliver Oliver Xu(徐永) Aigine InfoTech Co.（语擎科技） W: <http://www.aigine.com> www.aigine.com T: +86-189189 02886 E: <mailto:oliver...@aigine.com> oliver...@aigine.com MSN: oliver_xuy...@msn.com Weibo: 语擎-集体智慧编程
