Mailing-List: contact java-dev-help@lucene.apache.org; run by ezmlm
Precedence: bulk
Reply-To: java-dev@lucene.apache.org
Message-ID: <521571584.1242762585558.JavaMail.jira@brutus>
Date: Tue, 19 May 2009 12:49:45 -0700 (PDT)
From: "Yonik Seeley (JIRA)" <jira@apache.org>
To: java-dev@lucene.apache.org
Subject: [jira] Commented: (LUCENE-1614) Add next() and skipTo() variants to
 DocIdSetIterator that return the current doc, instead of boolean
In-Reply-To: <848873297.1240634970628.JavaMail.jira@brutus>
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit


    [ https://issues.apache.org/jira/browse/LUCENE-1614?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12710848#action_12710848 ] 

Yonik Seeley commented on LUCENE-1614:
--------------------------------------

bq. Not sure - didn't we agree for >= current?

"A bigger question though, is if we should support skipTo(doc) where doc<=current at all"
implies well defined behavior only when doc>current, as all of our scorers adhere to.

bq. BTW, none of the existing iterators in the code needed to perform any extra check to ensure that behavior. Even TermScorer.

Hmmm... TermScorer.skipTo() does first advance the pointer before checking any state.  If we wanted to support calling skipTo(10) twice in a row, it would require extra code.

> Add next() and skipTo() variants to DocIdSetIterator that return the current doc, instead of boolean
> ----------------------------------------------------------------------------------------------------
>
>                 Key: LUCENE-1614
>                 URL: https://issues.apache.org/jira/browse/LUCENE-1614
>             Project: Lucene - Java
>          Issue Type: Improvement
>          Components: Search
>            Reporter: Shai Erera
>             Fix For: 2.9
>
>         Attachments: LUCENE-1614.patch
>
>
> See http://www.nabble.com/Another-possible-optimization---now-in-DocIdSetIterator-p23223319.html for the full discussion. The basic idea is to add variants to those two methods that return the current doc they are at, to save successive calls to doc(). If there are no more docs, return -1. A summary of what was discussed so far:
> # Deprecate those two methods.
> # Add nextDoc() and skipToDoc(int) that return doc, with default impl in DISI (calls next() and skipTo() respectively, and will be changed to abstract in 3.0).
> #* I actually would like to propose an alternative to the names: advance() and advance(int) - the first advances by one, the second advances to target.
> # Wherever these are used, do something like '(doc = advance()) >= 0' instead of comparing to -1 for improved performance.
> I will post a patch shortly

-- 
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