[ http://issues.apache.org/jira/browse/LUCENE-584?page=comments#action_12434901 ] Paul Elschot commented on LUCENE-584: -------------------------------------
In the inheritance from Matcher to Scorer there is an asymmetry in this patch. Matcher provides a default implementation for Matcher.explain() but Scorer does not, and this might lead to unexpected surprises for future Scorers when the current Matcher.explain() is used. One could add an abstract Scorer.explain() to catch these, or provide a default implementation for Scorer.explain(). With matcher implementations quite a few other implementation decisions need to be taken. Also any place in the current code where a Scorer is used, but none of the Scorer.score() methods, is a candidate for a change from Scorer to Matcher. This will be mostly the current filtering implementations, but ConstantScoringQuery is another nice example. Regards, Paul Elschot > Decouple Filter from BitSet > --------------------------- > > Key: LUCENE-584 > URL: http://issues.apache.org/jira/browse/LUCENE-584 > Project: Lucene - Java > Issue Type: Improvement > Components: Search > Affects Versions: 2.0.1 > Reporter: Peter Schäfer > Priority: Minor > Attachments: BitsMatcher.java, Filter-20060628.patch, > HitCollector-20060628.patch, IndexSearcher-20060628.patch, > MatchCollector.java, Matcher.java, Matcher20060830b.patch, > Scorer-20060628.patch, Searchable-20060628.patch, Searcher-20060628.patch, > Some Matchers.zip, SortedVIntList.java, TestSortedVIntList.java > > > {code} > package org.apache.lucene.search; > public abstract class Filter implements java.io.Serializable > { > public abstract AbstractBitSet bits(IndexReader reader) throws IOException; > } > public interface AbstractBitSet > { > public boolean get(int index); > } > {code} > It would be useful if the method =Filter.bits()= returned an abstract > interface, instead of =java.util.BitSet=. > Use case: there is a very large index, and, depending on the user's > privileges, only a small portion of the index is actually visible. > Sparsely populated =java.util.BitSet=s are not efficient and waste lots of > memory. It would be desirable to have an alternative BitSet implementation > with smaller memory footprint. > Though it _is_ possibly to derive classes from =java.util.BitSet=, it was > obviously not designed for that purpose. > That's why I propose to use an interface instead. The default implementation > could still delegate to =java.util.BitSet=. -- This message is automatically generated by JIRA. - If you think it was sent incorrectly contact one of the administrators: http://issues.apache.org/jira/secure/Administrators.jspa - For more information on JIRA, see: http://www.atlassian.com/software/jira --------------------------------------------------------------------- To unsubscribe, e-mail: [EMAIL PROTECTED] For additional commands, e-mail: [EMAIL PROTECTED]
