[LUCENE-6278] Remove Scorer.freq()

• Type: Improvement
• Status: Closed
• Priority: Minor
• Resolution: Fixed
• Fix Version/s: 7.2
• Lucene Fields: New
• Assignee: Alan Woodward
• Reporter: Alan Woodward
• Created: 21/Feb/15 17:25
• Updated: 22/Dec/17 08:32
• Resolved: 15/Nov/17 12:20

Description

At the moment, Scorer.freq() does different things depending on the Scorer implementation:

• TermScorer and the phrase scorers return the frequency of that term or phrase in the current document. TermScorer.freq() is not actually called anywhere (apart from in a couple of tests), and XPhraseScorer.freq() is only called in PhraseWeight.explain()
• The various Boolean scorers return the number of matching subscorers, and are used for coord calculations.

I think this is confusing. I propose that we instead add a new coord() method to Scorer that by default returns 1, and that is overridden by the boolean scorers; and that we just remove freq() entirely. PhraseWeight.explain() can call a package-private method on XPhraseScorer.