package org.apache.lucene.search.join;
/*
* 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 org.apache.lucene.index.AtomicReaderContext;
import org.apache.lucene.index.DocsEnum;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.index.Terms;
import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.search.ComplexExplanation;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.Explanation;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.Scorer;
import org.apache.lucene.search.Weight;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.BytesRefHash;
import org.apache.lucene.util.FixedBitSet;
import java.io.IOException;
import java.util.Locale;
import java.util.Set;
class TermsIncludingScoreQuery extends Query {
final String field;
final boolean multipleValuesPerDocument;
final BytesRefHash terms;
final float[] scores;
final int[] ords;
final Query originalQuery;
final Query unwrittenOriginalQuery;
TermsIncludingScoreQuery(String field, boolean multipleValuesPerDocument, BytesRefHash terms, float[] scores, Query originalQuery) {
this.field = field;
this.multipleValuesPerDocument = multipleValuesPerDocument;
this.terms = terms;
this.scores = scores;
this.originalQuery = originalQuery;
this.ords = terms.sort(BytesRef.getUTF8SortedAsUnicodeComparator());
this.unwrittenOriginalQuery = originalQuery;
}
private TermsIncludingScoreQuery(String field, boolean multipleValuesPerDocument, BytesRefHash terms, float[] scores, int[] ords, Query originalQuery, Query unwrittenOriginalQuery) {
this.field = field;
this.multipleValuesPerDocument = multipleValuesPerDocument;
this.terms = terms;
this.scores = scores;
this.originalQuery = originalQuery;
this.ords = ords;
this.unwrittenOriginalQuery = unwrittenOriginalQuery;
}
public String toString(String string) {
return String.format(Locale.ROOT, "TermsIncludingScoreQuery{field=%s;originalQuery=%s}", field, unwrittenOriginalQuery);
}
@Override
public void extractTerms(Set<Term> terms) {
originalQuery.extractTerms(terms);
}
@Override
public Query rewrite(IndexReader reader) throws IOException {
final Query originalQueryRewrite = originalQuery.rewrite(reader);
if (originalQueryRewrite != originalQuery) {
Query rewritten = new TermsIncludingScoreQuery(field, multipleValuesPerDocument, terms, scores,
ords, originalQueryRewrite, originalQuery);
rewritten.setBoost(getBoost());
return rewritten;
} else {
return this;
}
}
@Override
public Weight createWeight(IndexSearcher searcher) throws IOException {
final Weight originalWeight = originalQuery.createWeight(searcher);
return new Weight() {
private TermsEnum segmentTermsEnum;
public Explanation explain(AtomicReaderContext context, int doc) throws IOException {
SVInnerScorer scorer = (SVInnerScorer) scorer(context, false, false, context.reader().getLiveDocs());
if (scorer != null) {
if (scorer.advanceForExplainOnly(doc) == doc) {
return scorer.explain();
}
}
return new ComplexExplanation(false, 0.0f, "Not a match");
}
public Query getQuery() {
return TermsIncludingScoreQuery.this;
}
public float getValueForNormalization() throws IOException {
return originalWeight.getValueForNormalization() * TermsIncludingScoreQuery.this.getBoost() * TermsIncludingScoreQuery.this.getBoost();
}
public void normalize(float norm, float topLevelBoost) {
originalWeight.normalize(norm, topLevelBoost * TermsIncludingScoreQuery.this.getBoost());
}
public Scorer scorer(AtomicReaderContext context, boolean scoreDocsInOrder, boolean topScorer, Bits acceptDocs) throws IOException {
Terms terms = context.reader().terms(field);
if (terms == null) {
return null;
}
segmentTermsEnum = terms.iterator(segmentTermsEnum);
if (scoreDocsInOrder) {
if (multipleValuesPerDocument) {
return new MVInOrderScorer(this, acceptDocs, segmentTermsEnum, context.reader().maxDoc());
} else {
return new SVInOrderScorer(this, acceptDocs, segmentTermsEnum, context.reader().maxDoc());
}
} else if (multipleValuesPerDocument) {
return new MVInnerScorer(this, acceptDocs, segmentTermsEnum, context.reader().maxDoc());
} else {
return new SVInnerScorer(this, acceptDocs, segmentTermsEnum);
}
}
};
}
// This impl assumes that the 'join' values are used uniquely per doc per field. Used for one to many relations.
class SVInnerScorer extends Scorer {
final BytesRef spare = new BytesRef();
final Bits acceptDocs;
final TermsEnum termsEnum;
int upto;
DocsEnum docsEnum;
DocsEnum reuse;
int scoreUpto;
SVInnerScorer(Weight weight, Bits acceptDocs, TermsEnum termsEnum) {
super(weight);
this.acceptDocs = acceptDocs;
this.termsEnum = termsEnum;
}
public float score() throws IOException {
return scores[ords[scoreUpto]];
}
public Explanation explain() throws IOException {
return new ComplexExplanation(true, score(), "Score based on join value " + termsEnum.term().utf8ToString());
}
public int docID() {
return docsEnum != null ? docsEnum.docID() : DocIdSetIterator.NO_MORE_DOCS;
}
public int nextDoc() throws IOException {
if (docsEnum != null) {
int docId = docsEnum.nextDoc();
if (docId == DocIdSetIterator.NO_MORE_DOCS) {
docsEnum = null;
} else {
return docId;
}
}
do {
if (upto == terms.size()) {
return DocIdSetIterator.NO_MORE_DOCS;
}
scoreUpto = upto;
if (termsEnum.seekExact(terms.get(ords[upto++], spare), true)) {
docsEnum = reuse = termsEnum.docs(acceptDocs, reuse, 0);
}
} while (docsEnum == null);
return docsEnum.nextDoc();
}
public int advance(int target) throws IOException {
throw new UnsupportedOperationException("advance() isn't supported because doc ids are emitted out of order");
}
private int advanceForExplainOnly(int target) throws IOException {
int docId;
do {
docId = nextDoc();
if (docId < target) {
int tempDocId = docsEnum.advance(target);
if (tempDocId == target) {
docId = tempDocId;
break;
}
} else if (docId == target) {
break;
}
docsEnum = null; // goto the next ord.
} while (docId != DocIdSetIterator.NO_MORE_DOCS);
return docId;
}
@Override
public float freq() {
return 1;
}
}
// This impl that tracks whether a docid has already been emitted. This check makes sure that docs aren't emitted
// twice for different join values. This means that the first encountered join value determines the score of a document
// even if other join values yield a higher score.
class MVInnerScorer extends SVInnerScorer {
final FixedBitSet alreadyEmittedDocs;
MVInnerScorer(Weight weight, Bits acceptDocs, TermsEnum termsEnum, int maxDoc) {
super(weight, acceptDocs, termsEnum);
alreadyEmittedDocs = new FixedBitSet(maxDoc);
}
public int nextDoc() throws IOException {
if (docsEnum != null) {
int docId;
do {
docId = docsEnum.nextDoc();
if (docId == DocIdSetIterator.NO_MORE_DOCS) {
break;
}
} while (alreadyEmittedDocs.get(docId));
if (docId == DocIdSetIterator.NO_MORE_DOCS) {
docsEnum = null;
} else {
alreadyEmittedDocs.set(docId);
return docId;
}
}
for (;;) {
do {
if (upto == terms.size()) {
return DocIdSetIterator.NO_MORE_DOCS;
}
scoreUpto = upto;
if (termsEnum.seekExact(terms.get(ords[upto++], spare), true)) {
docsEnum = reuse = termsEnum.docs(acceptDocs, reuse, 0);
}
} while (docsEnum == null);
int docId;
do {
docId = docsEnum.nextDoc();
if (docId == DocIdSetIterator.NO_MORE_DOCS) {
break;
}
} while (alreadyEmittedDocs.get(docId));
if (docId == DocIdSetIterator.NO_MORE_DOCS) {
docsEnum = null;
} else {
alreadyEmittedDocs.set(docId);
return docId;
}
}
}
}
class SVInOrderScorer extends Scorer {
final DocIdSetIterator matchingDocsIterator;
final float[] scores;
int currentDoc = -1;
SVInOrderScorer(Weight weight, Bits acceptDocs, TermsEnum termsEnum, int maxDoc) throws IOException {
super(weight);
FixedBitSet matchingDocs = new FixedBitSet(maxDoc);
this.scores = new float[maxDoc];
fillDocsAndScores(matchingDocs, acceptDocs, termsEnum);
this.matchingDocsIterator = matchingDocs.iterator();
}
protected void fillDocsAndScores(FixedBitSet matchingDocs, Bits acceptDocs, TermsEnum termsEnum) throws IOException {
BytesRef spare = new BytesRef();
DocsEnum docsEnum = null;
for (int i = 0; i < terms.size(); i++) {
if (termsEnum.seekExact(terms.get(ords[i], spare), true)) {
docsEnum = termsEnum.docs(acceptDocs, docsEnum, 0);
float score = TermsIncludingScoreQuery.this.scores[ords[i]];
for (int doc = docsEnum.nextDoc(); doc != DocIdSetIterator.NO_MORE_DOCS; doc = docsEnum.nextDoc()) {
matchingDocs.set(doc);
// In the case the same doc is also related to a another doc, a score might be overwritten. I think this
// can only happen in a many-to-many relation
scores[doc] = score;
}
}
}
}
public float score() throws IOException {
return scores[currentDoc];
}
public float freq() throws IOException {
return 1;
}
public int docID() {
return currentDoc;
}
public int nextDoc() throws IOException {
return currentDoc = matchingDocsIterator.nextDoc();
}
public int advance(int target) throws IOException {
return currentDoc = matchingDocsIterator.advance(target);
}
}
// This scorer deals with the fact that a document can have more than one score from multiple related documents.
class MVInOrderScorer extends SVInOrderScorer {
MVInOrderScorer(Weight weight, Bits acceptDocs, TermsEnum termsEnum, int maxDoc) throws IOException {
super(weight, acceptDocs, termsEnum, maxDoc);
}
@Override
protected void fillDocsAndScores(FixedBitSet matchingDocs, Bits acceptDocs, TermsEnum termsEnum) throws IOException {
BytesRef spare = new BytesRef();
DocsEnum docsEnum = null;
for (int i = 0; i < terms.size(); i++) {
if (termsEnum.seekExact(terms.get(ords[i], spare), true)) {
docsEnum = termsEnum.docs(acceptDocs, docsEnum, 0);
float score = TermsIncludingScoreQuery.this.scores[ords[i]];
for (int doc = docsEnum.nextDoc(); doc != DocIdSetIterator.NO_MORE_DOCS; doc = docsEnum.nextDoc()) {
// I prefer this:
/*if (scores[doc] < score) {
scores[doc] = score;
matchingDocs.set(doc);
}*/
// But this behaves the same as MVInnerScorer and only then the tests will pass:
if (!matchingDocs.get(doc)) {
scores[doc] = score;
matchingDocs.set(doc);
}
}
}
}
}
}
}