* NOTE: even if scoreDocsInOrder is false, it is
* recommended to check whether the returned Scorer indeed scores
- * documents out of order (i.e., call {@link #scoresDocsOutOfOrder()}), as some
- * Scorer implementations will always return documents in-order.
+ * documents out of order (i.e., call {@link #scoresDocsOutOfOrder()}), as
+ * some Scorer implementations will always return documents
+ * in-order.
+ * NOTE: null can be returned if no documents will be scored by this
+ * query.
*
* @param reader
* the {@link IndexReader} for which to return the {@link Scorer}.
Index: src/java/org/apache/lucene/search/MultiPhraseQuery.java
===================================================================
--- src/java/org/apache/lucene/search/MultiPhraseQuery.java (revision 797728)
+++ src/java/org/apache/lucene/search/MultiPhraseQuery.java (working copy)
@@ -217,7 +217,11 @@
fieldExpl.setDescription("fieldWeight("+getQuery()+" in "+doc+
"), product of:");
- Explanation tfExpl = scorer(reader, true, false).explain(doc);
+ Scorer scorer = scorer(reader, true, false);
+ if (scorer == null) {
+ return new Explanation(0.0f, "no matching docs");
+ }
+ Explanation tfExpl = scorer.explain(doc);
fieldExpl.addDetail(tfExpl);
fieldExpl.addDetail(idfExpl);
Index: src/java/org/apache/lucene/search/FilteredQuery.java
===================================================================
--- src/java/org/apache/lucene/search/FilteredQuery.java (revision 797728)
+++ src/java/org/apache/lucene/search/FilteredQuery.java (working copy)
@@ -82,7 +82,11 @@
inner.addDetail(preBoost);
}
Filter f = FilteredQuery.this.filter;
- DocIdSetIterator docIdSetIterator = f.getDocIdSet(ir).iterator();
+ DocIdSet docIdSet = f.getDocIdSet(ir);
+ DocIdSetIterator docIdSetIterator = docIdSet == null ? EmptyDocIdSetIterator.getInstance() : docIdSet.iterator();
+ if (docIdSetIterator == null) {
+ docIdSetIterator = EmptyDocIdSetIterator.getInstance();
+ }
if (docIdSetIterator.advance(i) == i) {
return inner;
} else {
@@ -100,7 +104,17 @@
public Scorer scorer(IndexReader indexReader, boolean scoreDocsInOrder, boolean topScorer)
throws IOException {
final Scorer scorer = weight.scorer(indexReader, scoreDocsInOrder, false);
- final DocIdSetIterator docIdSetIterator = filter.getDocIdSet(indexReader).iterator();
+ if (scorer == null) {
+ return null;
+ }
+ DocIdSet docIdSet = filter.getDocIdSet(indexReader);
+ if (docIdSet == null) {
+ return null;
+ }
+ final DocIdSetIterator docIdSetIterator = docIdSet.iterator();
+ if (docIdSetIterator == null) {
+ return null;
+ }
return new Scorer(similarity) {
Index: src/java/org/apache/lucene/search/CachingWrapperFilter.java
===================================================================
--- src/java/org/apache/lucene/search/CachingWrapperFilter.java (revision 797728)
+++ src/java/org/apache/lucene/search/CachingWrapperFilter.java (working copy)
@@ -100,12 +100,13 @@
final DocIdSet docIdSet = docIdSetToCache(filter.getDocIdSet(reader), reader);
- synchronized (cache) { // update cache
- cache.put(reader, docIdSet);
+ if (docIdSet != null) {
+ synchronized (cache) { // update cache
+ cache.put(reader, docIdSet);
+ }
}
return docIdSet;
-
}
public String toString() {
Index: src/java/org/apache/lucene/search/function/CustomScoreQuery.java
===================================================================
--- src/java/org/apache/lucene/search/function/CustomScoreQuery.java (revision 797728)
+++ src/java/org/apache/lucene/search/function/CustomScoreQuery.java (working copy)
@@ -331,6 +331,9 @@
// false for "topScorer" because we will not invoke
// score(Collector) on these scorers:
Scorer subQueryScorer = subQueryWeight.scorer(reader, true, false);
+ if (subQueryScorer == null) {
+ return null;
+ }
Scorer[] valSrcScorers = new Scorer[valSrcWeights.length];
for(int i = 0; i < valSrcScorers.length; i++) {
valSrcScorers[i] = valSrcWeights[i].scorer(reader, true, false);
@@ -339,7 +342,8 @@
}
public Explanation explain(IndexReader reader, int doc) throws IOException {
- return scorer(reader, true, false).explain(doc);
+ Scorer scorer = scorer(reader, true, false);
+ return scorer == null ? new Explanation(0.0f, "no matching docs") : scorer.explain(doc);
}
public boolean scoresDocsOutOfOrder() {
Index: src/java/org/apache/lucene/search/BooleanQuery.java
===================================================================
--- src/java/org/apache/lucene/search/BooleanQuery.java (revision 797728)
+++ src/java/org/apache/lucene/search/BooleanQuery.java (working copy)
@@ -227,9 +227,12 @@
float sum = 0.0f;
boolean fail = false;
int shouldMatchCount = 0;
- for (int i = 0 ; i < weights.size(); i++) {
- BooleanClause c = (BooleanClause)clauses.get(i);
- QueryWeight w = (QueryWeight)weights.get(i);
+ for (Iterator wIter = weights.iterator(), cIter = clauses.iterator(); wIter.hasNext();) {
+ QueryWeight w = (QueryWeight) wIter.next();
+ BooleanClause c = (BooleanClause) cIter.next();
+ if (w.scorer(reader, true, true) == null) {
+ continue;
+ }
Explanation e = w.explain(reader, doc);
if (!c.isProhibited()) maxCoord++;
if (e.isMatch()) {
@@ -244,7 +247,7 @@
sumExpl.addDetail(r);
fail = true;
}
- if (c.getOccur().equals(Occur.SHOULD))
+ if (c.getOccur() == Occur.SHOULD)
shouldMatchCount++;
} else if (c.isRequired()) {
Explanation r = new Explanation(0.0f, "no match on required clause (" + c.getQuery().toString() + ")");
@@ -312,6 +315,16 @@
return new BooleanScorer(similarity, minNrShouldMatch, optional, prohibited);
}
+ if (required.size() == 0 && optional.size() == 0) {
+ // no required and optional clauses.
+ return null;
+ } else if (optional.size() < minNrShouldMatch) {
+ // either >1 req scorer, or there are 0 req scorers and at least 1
+ // optional scorer. Therefore if there are not enough optional scorers
+ // no documents will be matched by the query
+ return null;
+ }
+
// Return a BooleanScorer2
return new BooleanScorer2(similarity, minNrShouldMatch, required, prohibited, optional);
}
Index: src/java/org/apache/lucene/search/PhraseQuery.java
===================================================================
--- src/java/org/apache/lucene/search/PhraseQuery.java (revision 797728)
+++ src/java/org/apache/lucene/search/PhraseQuery.java (working copy)
@@ -209,7 +209,11 @@
fieldExpl.setDescription("fieldWeight("+field+":"+query+" in "+doc+
"), product of:");
- Explanation tfExpl = scorer(reader, true, false).explain(doc);
+ Scorer scorer = scorer(reader, true, false);
+ if (scorer == null) {
+ return new Explanation(0.0f, "no matching docs");
+ }
+ Explanation tfExpl = scorer.explain(doc);
fieldExpl.addDetail(tfExpl);
fieldExpl.addDetail(idfExpl);
Index: src/java/org/apache/lucene/search/DocIdSet.java
===================================================================
--- src/java/org/apache/lucene/search/DocIdSet.java (revision 797728)
+++ src/java/org/apache/lucene/search/DocIdSet.java (working copy)
@@ -30,6 +30,8 @@
* implemented using a {@link SortedVIntList}). */
public static final DocIdSet EMPTY_DOCIDSET = new SortedVIntList(new int[0]);
- /** Provides a {@link DocIdSetIterator} to access the set. */
+ /** Provides a {@link DocIdSetIterator} to access the set.
+ * This may (but is not required to) return null if there
+ * are no docs that match. */
public abstract DocIdSetIterator iterator() throws IOException;
}
Index: src/java/org/apache/lucene/search/NonMatchingScorer.java
===================================================================
--- src/java/org/apache/lucene/search/NonMatchingScorer.java (revision 797728)
+++ src/java/org/apache/lucene/search/NonMatchingScorer.java (working copy)
@@ -1,50 +0,0 @@
-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;
-
-/** A scorer that matches no document at all. */
-class NonMatchingScorer extends Scorer {
- public NonMatchingScorer() { super(null); } // no similarity used
-
- /** @deprecated use {@link #docID()} instead. */
- public int doc() { throw new UnsupportedOperationException(); }
-
- public int docID() { return NO_MORE_DOCS; }
-
- /** @deprecated use {@link #nextDoc()} instead. */
- public boolean next() throws IOException { return false; }
-
- public int nextDoc() throws IOException { return NO_MORE_DOCS; }
-
- public float score() { throw new UnsupportedOperationException(); }
-
- /** @deprecated use {@link #advance(int)} instead. */
- public boolean skipTo(int target) { return false; }
-
- public int advance(int target) { return NO_MORE_DOCS; }
-
- public Explanation explain(int doc) {
- Explanation e = new Explanation();
- e.setDescription("No document matches.");
- return e;
- }
-}
-
-
Index: src/java/org/apache/lucene/search/IndexSearcher.java
===================================================================
--- src/java/org/apache/lucene/search/IndexSearcher.java (revision 797728)
+++ src/java/org/apache/lucene/search/IndexSearcher.java (working copy)
@@ -267,8 +267,17 @@
assert docID == -1 || docID == DocIdSetIterator.NO_MORE_DOCS;
// CHECKME: use ConjunctionScorer here?
- DocIdSetIterator filterIter = filter.getDocIdSet(reader).iterator();
+ DocIdSet filterDocIdSet = filter.getDocIdSet(reader);
+ if (filterDocIdSet == null) {
+ // this means the filter does not accept any documents.
+ return;
+ }
+ DocIdSetIterator filterIter = filterDocIdSet.iterator();
+ if (filterIter == null) {
+ // this means the filter does not accept any documents.
+ return;
+ }
int filterDoc = filterIter.nextDoc();
int scorerDoc = scorer.advance(filterDoc);
Index: src/java/org/apache/lucene/index/DocumentsWriter.java
===================================================================
--- src/java/org/apache/lucene/index/DocumentsWriter.java (revision 797728)
+++ src/java/org/apache/lucene/index/DocumentsWriter.java (working copy)
@@ -1007,12 +1007,14 @@
int limit = ((Integer) entry.getValue()).intValue();
QueryWeight weight = query.queryWeight(searcher);
Scorer scorer = weight.scorer(reader, true, false);
- while(true) {
- int doc = scorer.nextDoc();
- if (((long) docIDStart) + doc >= limit)
- break;
- reader.deleteDocument(doc);
- any = true;
+ if (scorer != null) {
+ while(true) {
+ int doc = scorer.nextDoc();
+ if (((long) docIDStart) + doc >= limit)
+ break;
+ reader.deleteDocument(doc);
+ any = true;
+ }
}
}
searcher.close();
Index: contrib/miscellaneous/src/java/org/apache/lucene/misc/ChainedFilter.java
===================================================================
--- contrib/miscellaneous/src/java/org/apache/lucene/misc/ChainedFilter.java (revision 797728)
+++ contrib/miscellaneous/src/java/org/apache/lucene/misc/ChainedFilter.java (working copy)
@@ -60,6 +60,7 @@
import java.io.IOException;
import org.apache.lucene.search.DocIdSet;
import org.apache.lucene.search.DocIdSetIterator;
+import org.apache.lucene.search.EmptyDocIdSetIterator;
import org.apache.lucene.util.OpenBitSet;
import org.apache.lucene.util.OpenBitSetDISI;
import org.apache.lucene.util.SortedVIntList;
@@ -146,9 +147,18 @@
}
private DocIdSetIterator getDISI(Filter filter, IndexReader reader)
- throws IOException
- {
- return filter.getDocIdSet(reader).iterator();
+ throws IOException {
+ DocIdSet docIdSet = filter.getDocIdSet(reader);
+ if (docIdSet == null) {
+ return EmptyDocIdSetIterator.getInstance();
+ } else {
+ DocIdSetIterator iter = docIdSet.iterator();
+ if (iter == null) {
+ return EmptyDocIdSetIterator.getInstance();
+ } else {
+ return iter;
+ }
+ }
}
private OpenBitSetDISI initialResult(IndexReader reader, int logic, int[] index)
@@ -241,13 +251,11 @@
}
private void doChain(OpenBitSetDISI result, int logic, DocIdSet dis)
- throws IOException
- {
+ throws IOException {
if (dis instanceof OpenBitSet) {
// optimized case for OpenBitSets
- switch (logic)
- {
+ switch (logic) {
case OR:
result.or((OpenBitSet) dis);
break;
@@ -265,9 +273,17 @@
break;
}
} else {
- DocIdSetIterator disi = dis.iterator();
- switch (logic)
- {
+ DocIdSetIterator disi;
+ if (dis == null) {
+ disi = EmptyDocIdSetIterator.getInstance();
+ } else {
+ disi = dis.iterator();
+ if (disi == null) {
+ disi = EmptyDocIdSetIterator.getInstance();
+ }
+ }
+
+ switch (logic) {
case OR:
result.inPlaceOr(disi);
break;