And BTW, now that I look at DIS.EMPTY, I think it can be improved by
defining it like this:
public static final DocIdSet EMPTY_DOCIDSET = new SortedVIntList(new
int[0]) {
public DocIdSetIterator iterator() {
return EmptyDocIdSetIterator.getInstance();
}
};
Instead of having its iterator() always creating a new instance, it can
return EmptyDISI's single instance.
I can open an issue, but I think this can be committed quite trivially by
one of the committers.
Shai
On Mon, Jul 27, 2009 at 1:26 PM, Uwe Schindler <[email protected]> wrote:
> Right, and you can simply get an iterator from it.
>
> -----
> Uwe Schindler
> H.-H.-Meier-Allee 63, D-28213 Bremen
> http://www.thetaphi.de
> eMail: [email protected]
>
> > -----Original Message-----
> > From: Robert Muir [mailto:[email protected]]
> > Sent: Monday, July 27, 2009 12:24 PM
> > To: [email protected]
> > Subject: Re: svn commit: r798091 -
> >
> /lucene/java/trunk/src/java/org/apache/lucene/search/EmptyDocIdSetIterator
> > .java
> >
> > here it is: DocIdSet.EMPTY_DOCIDSET
> >
> > /** An empty {...@code DocIdSet} instance for easy use (this is currently
> > * implemented using a {...@link SortedVIntList}). */
> >
> > On Mon, Jul 27, 2009 at 6:18 AM, Uwe Schindler<[email protected]> wrote:
> > > Why do we need this class? There is already a static final empty
> > iterator
> > > available in DocIdSetIterator.EMPTY_DOCIDSET_ITERATOR (or something
> like
> > > that name)?
> > >
> > > -----
> > > Uwe Schindler
> > > H.-H.-Meier-Allee 63, D-28213 Bremen
> > > http://www.thetaphi.de
> > > eMail: [email protected]
> > >
> > >> From: [email protected] [mailto:[email protected]]
> > >> Sent: Monday, July 27, 2009 12:03 PM
> > >> To: [email protected]
> > >> Subject: svn commit: r798091 -
> > >>
> >
> /lucene/java/trunk/src/java/org/apache/lucene/search/EmptyDocIdSetIterator
> > >> .java
> > >>
> > >> Author: mikemccand
> > >> Date: Mon Jul 27 10:02:34 2009
> > >> New Revision: 798091
> > >>
> > >> URL: http://svn.apache.org/viewvc?rev=798091&view=rev
> > >> Log:
> > >> LUCENE-1754: add EmptyDocIdSetIterator
> > >>
> > >> Added:
> > >>
> > >>
> >
> lucene/java/trunk/src/java/org/apache/lucene/search/EmptyDocIdSetIterator.
> > >> java (with props)
> > >>
> > >> Added:
> > >>
> >
> lucene/java/trunk/src/java/org/apache/lucene/search/EmptyDocIdSetIterator.
> > >> java
> > >> URL:
> > >>
> >
> http://svn.apache.org/viewvc/lucene/java/trunk/src/java/org/apache/lucene/
> > >> search/EmptyDocIdSetIterator.java?rev=798091&view=auto
> > >>
> >
> ==========================================================================
> > >> ====
> > >> ---
> > >>
> >
> lucene/java/trunk/src/java/org/apache/lucene/search/EmptyDocIdSetIterator.
> > >> java (added)
> > >> +++
> > >>
> >
> lucene/java/trunk/src/java/org/apache/lucene/search/EmptyDocIdSetIterator.
> > >> java Mon Jul 27 10:02:34 2009
> > >> @@ -0,0 +1,42 @@
> > >> +package org.apache.lucene.search;
> > >> +
> > >> +/**
> > >> + * Licensed to the Apache Software Foundation (ASF) under one or more
> > >> + * contributor license agreements. See the NOTICE file distributed
> > with
> > >> + * this work for additional information regarding copyright
> ownership.
> > >> + * The ASF licenses this file to You under the Apache License,
> Version
> > >> 2.0
> > >> + * (the "License"); you may not use this file except in compliance
> > with
> > >> + * the License. You may obtain a copy of the License at
> > >> + *
> > >> + * http://www.apache.org/licenses/LICENSE-2.0
> > >> + *
> > >> + * Unless required by applicable law or agreed to in writing,
> software
> > >> + * distributed under the License is distributed on an "AS IS" BASIS,
> > >> + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
> > >> implied.
> > >> + * See the License for the specific language governing permissions
> and
> > >> + * limitations under the License.
> > >> + */
> > >> +
> > >> +import java.io.IOException;
> > >> +
> > >> +/**
> > >> + * An empty implementation for {...@link DocIdSetIterator}. This can be
> > used
> > >> by
> > >> + * classes which receive a null {...@link DocIdSet} from
> > >> + * {...@link Filter#getDocIdSet(org.apache.lucene.index.IndexReader)}.
> > >> + */
> > >> +public final class EmptyDocIdSetIterator extends DocIdSetIterator {
> > >> +
> > >> + private static final DocIdSetIterator instance = new
> > >> EmptyDocIdSetIterator();
> > >> +
> > >> + public static DocIdSetIterator getInstance() { return instance; }
> > >> +
> > >> + // to prevent instantiation
> > >> + private EmptyDocIdSetIterator() { }
> > >> +
> > >> + public int advance(int target) throws IOException { return
> > >> NO_MORE_DOCS; }
> > >> +
> > >> + public int docID() { return NO_MORE_DOCS; }
> > >> +
> > >> + public int nextDoc() throws IOException { return NO_MORE_DOCS; }
> > >> +
> > >> +}
> > >>
> > >> Propchange:
> > >>
> >
> lucene/java/trunk/src/java/org/apache/lucene/search/EmptyDocIdSetIterator.
> > >> java
> > >>
> -----------------------------------------------------------------------
> > ---
> > >> ----
> > >> svn:eol-style = native
> > >>
> > >
> > >
> > >
> > > ---------------------------------------------------------------------
> > > To unsubscribe, e-mail: [email protected]
> > > For additional commands, e-mail: [email protected]
> > >
> > >
> >
> >
> >
> > --
> > Robert Muir
> > [email protected]
> >
> > ---------------------------------------------------------------------
> > To unsubscribe, e-mail: [email protected]
> > For additional commands, e-mail: [email protected]
>
>
>
> ---------------------------------------------------------------------
> To unsubscribe, e-mail: [email protected]
> For additional commands, e-mail: [email protected]
>
>
