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: u...@thetaphi.de > From: mikemcc...@apache.org [mailto:mikemcc...@apache.org] > Sent: Monday, July 27, 2009 12:03 PM > To: java-comm...@lucene.apache.org > 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: java-dev-unsubscr...@lucene.apache.org For additional commands, e-mail: java-dev-h...@lucene.apache.org
