lucene-dev mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Paul Elschot (JIRA)" <j...@apache.org>
Subject [jira] Commented: (LUCENE-584) Decouple Filter from BitSet
Date Wed, 25 Jul 2007 15:10:31 GMT

    [ https://issues.apache.org/jira/browse/LUCENE-584?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel#action_12515313
] 

Paul Elschot commented on LUCENE-584:
-------------------------------------

There is some code in contrib where a Filter is assumed to have BitSet available:

contrib/queries/src/java/org/apache/lucene/search/BooleanFilter.java
contrib/miscellaneous/src/java/org/apache/lucene/misc/ChainedFilter.java

When Filter is going to move from BitSet to Matcher, these will have to be reimplemented.
They basically use Filters to provide BitSets, but it seems to me that they also
could use lists of BitSets, for example.


> Decouple Filter from BitSet
> ---------------------------
>
>                 Key: LUCENE-584
>                 URL: https://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: bench-diff.txt, bench-diff.txt, BitsMatcher.java, DefaultMatcher20070725.patch,
Filter-20060628.patch, HitCollector-20060628.patch, IndexSearcher-20060628.patch, MatchCollector.java,
Matcher.java, Matcher20070226.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.
-
You can reply to this email to add a comment to the issue online.


---------------------------------------------------------------------
To unsubscribe, e-mail: java-dev-unsubscribe@lucene.apache.org
For additional commands, e-mail: java-dev-help@lucene.apache.org


Mime
View raw message