org.apache.lucene.search.vectorhighlight.FieldQuery Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of lucene-highlighter Show documentation
Show all versions of lucene-highlighter Show documentation
This is the highlighter for apache lucene java
/*
* 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.
*/
package org.apache.lucene.search.vectorhighlight;
import java.io.IOException;
import java.util.Collection;
import java.util.HashMap;
import java.util.HashSet;
import java.util.Iterator;
import java.util.LinkedHashSet;
import java.util.List;
import java.util.Map;
import java.util.Set;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.Term;
import org.apache.lucene.queries.function.FunctionScoreQuery;
import org.apache.lucene.search.BooleanClause;
import org.apache.lucene.search.BooleanQuery;
import org.apache.lucene.search.BoostQuery;
import org.apache.lucene.search.ConstantScoreQuery;
import org.apache.lucene.search.DisjunctionMaxQuery;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.MultiTermQuery;
import org.apache.lucene.search.PhraseQuery;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.SynonymQuery;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.vectorhighlight.FieldTermStack.TermInfo;
/**
* FieldQuery breaks down query object into terms/phrases and keeps them in a QueryPhraseMap
* structure.
*/
public class FieldQuery {
final boolean fieldMatch;
// fieldMatch==true, Map
// fieldMatch==false, Map
Map rootMaps = new HashMap<>();
// fieldMatch==true, Map
// fieldMatch==false, Map
Map> termSetMap = new HashMap<>();
int termOrPhraseNumber; // used for colored tag support
// The maximum number of different matching terms accumulated from any one MultiTermQuery
private static final int MAX_MTQ_TERMS = 1024;
public FieldQuery(Query query, IndexReader reader, boolean phraseHighlight, boolean fieldMatch)
throws IOException {
this.fieldMatch = fieldMatch;
Set flatQueries = new LinkedHashSet<>();
IndexSearcher searcher;
if (reader == null) {
searcher = null;
} else {
searcher = new IndexSearcher(reader);
}
flatten(query, searcher, flatQueries, 1f);
saveTerms(flatQueries, searcher);
Collection expandQueries = expand(flatQueries);
for (Query flatQuery : expandQueries) {
QueryPhraseMap rootMap = getRootMap(flatQuery);
rootMap.add(flatQuery, reader);
float boost = 1f;
while (flatQuery instanceof BoostQuery) {
BoostQuery bq = (BoostQuery) flatQuery;
flatQuery = bq.getQuery();
boost *= bq.getBoost();
}
if (!phraseHighlight && flatQuery instanceof PhraseQuery) {
PhraseQuery pq = (PhraseQuery) flatQuery;
if (pq.getTerms().length > 1) {
for (Term term : pq.getTerms()) rootMap.addTerm(term, boost);
}
}
}
}
/**
* For backwards compatibility you can initialize FieldQuery without an IndexReader, which is only
* required to support MultiTermQuery
*/
FieldQuery(Query query, boolean phraseHighlight, boolean fieldMatch) throws IOException {
this(query, null, phraseHighlight, fieldMatch);
}
protected void flatten(
Query sourceQuery, IndexSearcher searcher, Collection flatQueries, float boost)
throws IOException {
while (sourceQuery instanceof BoostQuery) {
BoostQuery bq = (BoostQuery) sourceQuery;
sourceQuery = bq.getQuery();
boost *= bq.getBoost();
}
if (sourceQuery instanceof BooleanQuery) {
BooleanQuery bq = (BooleanQuery) sourceQuery;
for (BooleanClause clause : bq) {
if (!clause.isProhibited()) {
flatten(clause.getQuery(), searcher, flatQueries, boost);
}
}
} else if (sourceQuery instanceof DisjunctionMaxQuery) {
DisjunctionMaxQuery dmq = (DisjunctionMaxQuery) sourceQuery;
for (Query query : dmq) {
flatten(query, searcher, flatQueries, boost);
}
} else if (sourceQuery instanceof TermQuery) {
if (boost != 1f) {
sourceQuery = new BoostQuery(sourceQuery, boost);
}
if (!flatQueries.contains(sourceQuery)) flatQueries.add(sourceQuery);
} else if (sourceQuery instanceof SynonymQuery) {
SynonymQuery synQuery = (SynonymQuery) sourceQuery;
for (Term term : synQuery.getTerms()) {
flatten(new TermQuery(term), searcher, flatQueries, boost);
}
} else if (sourceQuery instanceof PhraseQuery) {
PhraseQuery pq = (PhraseQuery) sourceQuery;
if (pq.getTerms().length == 1) sourceQuery = new TermQuery(pq.getTerms()[0]);
if (boost != 1f) {
sourceQuery = new BoostQuery(sourceQuery, boost);
}
flatQueries.add(sourceQuery);
} else if (sourceQuery instanceof ConstantScoreQuery) {
final Query q = ((ConstantScoreQuery) sourceQuery).getQuery();
if (q != null) {
flatten(q, searcher, flatQueries, boost);
}
} else if (sourceQuery instanceof FunctionScoreQuery) {
final Query q = ((FunctionScoreQuery) sourceQuery).getWrappedQuery();
if (q != null) {
flatten(q, searcher, flatQueries, boost);
}
} else if (searcher != null) {
Query query = sourceQuery;
Query rewritten;
if (sourceQuery instanceof MultiTermQuery) {
rewritten =
new MultiTermQuery.TopTermsScoringBooleanQueryRewrite(MAX_MTQ_TERMS)
.rewrite(searcher.getIndexReader(), (MultiTermQuery) query);
} else {
rewritten = query.rewrite(searcher);
}
if (rewritten != query) {
// only rewrite once and then flatten again - the rewritten query could have a speacial
// treatment
// if this method is overwritten in a subclass.
flatten(rewritten, searcher, flatQueries, boost);
}
// if the query is already rewritten we discard it
}
// else discard queries
}
/*
* Create expandQueries from flatQueries.
*
* expandQueries := flatQueries + overlapped phrase queries
*
* ex1) flatQueries={a,b,c}
* => expandQueries={a,b,c}
* ex2) flatQueries={a,"b c","c d"}
* => expandQueries={a,"b c","c d","b c d"}
*/
Collection expand(Collection flatQueries) {
Set expandQueries = new LinkedHashSet<>();
for (Iterator i = flatQueries.iterator(); i.hasNext(); ) {
Query query = i.next();
i.remove();
expandQueries.add(query);
float queryBoost = 1f;
while (query instanceof BoostQuery) {
BoostQuery bq = (BoostQuery) query;
queryBoost *= bq.getBoost();
query = bq.getQuery();
}
if (!(query instanceof PhraseQuery)) continue;
for (Iterator j = flatQueries.iterator(); j.hasNext(); ) {
Query qj = j.next();
float qjBoost = 1f;
while (qj instanceof BoostQuery) {
BoostQuery bq = (BoostQuery) qj;
qjBoost *= bq.getBoost();
qj = bq.getQuery();
}
if (!(qj instanceof PhraseQuery)) continue;
checkOverlap(expandQueries, (PhraseQuery) query, queryBoost, (PhraseQuery) qj, qjBoost);
}
}
return expandQueries;
}
/*
* Check if PhraseQuery A and B have overlapped part.
*
* ex1) A="a b", B="b c" => overlap; expandQueries={"a b c"}
* ex2) A="b c", B="a b" => overlap; expandQueries={"a b c"}
* ex3) A="a b", B="c d" => no overlap; expandQueries={}
*/
private void checkOverlap(
Collection expandQueries, PhraseQuery a, float aBoost, PhraseQuery b, float bBoost) {
if (a.getSlop() != b.getSlop()) return;
Term[] ats = a.getTerms();
Term[] bts = b.getTerms();
if (fieldMatch && !ats[0].field().equals(bts[0].field())) return;
checkOverlap(expandQueries, ats, bts, a.getSlop(), aBoost);
checkOverlap(expandQueries, bts, ats, b.getSlop(), bBoost);
}
/*
* Check if src and dest have overlapped part and if it is, create PhraseQueries and add expandQueries.
*
* ex1) src="a b", dest="c d" => no overlap
* ex2) src="a b", dest="a b c" => no overlap
* ex3) src="a b", dest="b c" => overlap; expandQueries={"a b c"}
* ex4) src="a b c", dest="b c d" => overlap; expandQueries={"a b c d"}
* ex5) src="a b c", dest="b c" => no overlap
* ex6) src="a b c", dest="b" => no overlap
* ex7) src="a a a a", dest="a a a" => overlap;
* expandQueries={"a a a a a","a a a a a a"}
* ex8) src="a b c d", dest="b c" => no overlap
*/
private void checkOverlap(
Collection expandQueries, Term[] src, Term[] dest, int slop, float boost) {
// beginning from 1 (not 0) is safe because that the PhraseQuery has multiple terms
// is guaranteed in flatten() method (if PhraseQuery has only one term, flatten()
// converts PhraseQuery to TermQuery)
for (int i = 1; i < src.length; i++) {
boolean overlap = true;
for (int j = i; j < src.length; j++) {
if ((j - i) < dest.length && !src[j].text().equals(dest[j - i].text())) {
overlap = false;
break;
}
}
if (overlap && src.length - i < dest.length) {
PhraseQuery.Builder pqBuilder = new PhraseQuery.Builder();
for (Term srcTerm : src) pqBuilder.add(srcTerm);
for (int k = src.length - i; k < dest.length; k++) {
pqBuilder.add(new Term(src[0].field(), dest[k].text()));
}
pqBuilder.setSlop(slop);
Query pq = pqBuilder.build();
if (boost != 1f) {
pq = new BoostQuery(pq, 1f);
}
if (!expandQueries.contains(pq)) expandQueries.add(pq);
}
}
}
QueryPhraseMap getRootMap(Query query) {
String key = getKey(query);
QueryPhraseMap map = rootMaps.get(key);
if (map == null) {
map = new QueryPhraseMap(this);
rootMaps.put(key, map);
}
return map;
}
/*
* Return 'key' string. 'key' is the field name of the Query.
* If not fieldMatch, 'key' will be null.
*/
private String getKey(Query query) {
if (!fieldMatch) return null;
while (query instanceof BoostQuery) {
query = ((BoostQuery) query).getQuery();
}
if (query instanceof TermQuery) return ((TermQuery) query).getTerm().field();
else if (query instanceof PhraseQuery) {
PhraseQuery pq = (PhraseQuery) query;
Term[] terms = pq.getTerms();
return terms[0].field();
} else if (query instanceof MultiTermQuery) {
return ((MultiTermQuery) query).getField();
} else throw new RuntimeException("query \"" + query.toString() + "\" must be flatten first.");
}
/*
* Save the set of terms in the queries to termSetMap.
*
* ex1) q=name:john
* - fieldMatch==true
* termSetMap=Map<"name",Set<"john">>
* - fieldMatch==false
* termSetMap=Map>
*
* ex2) q=name:john title:manager
* - fieldMatch==true
* termSetMap=Map<"name",Set<"john">,
* "title",Set<"manager">>
* - fieldMatch==false
* termSetMap=Map>
*
* ex3) q=name:"john lennon"
* - fieldMatch==true
* termSetMap=Map<"name",Set<"john","lennon">>
* - fieldMatch==false
* termSetMap=Map>
*/
void saveTerms(Collection flatQueries, IndexSearcher searcher) throws IOException {
for (Query query : flatQueries) {
while (query instanceof BoostQuery) {
query = ((BoostQuery) query).getQuery();
}
Set termSet = getTermSet(query);
if (query instanceof TermQuery) termSet.add(((TermQuery) query).getTerm().text());
else if (query instanceof PhraseQuery) {
for (Term term : ((PhraseQuery) query).getTerms()) termSet.add(term.text());
} else if (query instanceof MultiTermQuery && searcher != null) {
BooleanQuery mtqTerms = (BooleanQuery) query.rewrite(searcher);
for (BooleanClause clause : mtqTerms) {
termSet.add(((TermQuery) clause.getQuery()).getTerm().text());
}
} else
throw new RuntimeException("query \"" + query.toString() + "\" must be flatten first.");
}
}
private Set getTermSet(Query query) {
String key = getKey(query);
Set set = termSetMap.get(key);
if (set == null) {
set = new HashSet<>();
termSetMap.put(key, set);
}
return set;
}
Set getTermSet(String field) {
return termSetMap.get(fieldMatch ? field : null);
}
/**
* @return QueryPhraseMap
*/
public QueryPhraseMap getFieldTermMap(String fieldName, String term) {
QueryPhraseMap rootMap = getRootMap(fieldName);
return rootMap == null ? null : rootMap.subMap.get(term);
}
/**
* @return QueryPhraseMap
*/
public QueryPhraseMap searchPhrase(String fieldName, final List phraseCandidate) {
QueryPhraseMap root = getRootMap(fieldName);
if (root == null) return null;
return root.searchPhrase(phraseCandidate);
}
private QueryPhraseMap getRootMap(String fieldName) {
return rootMaps.get(fieldMatch ? fieldName : null);
}
int nextTermOrPhraseNumber() {
return termOrPhraseNumber++;
}
/** Internal structure of a query for highlighting: represents a nested query structure */
public static class QueryPhraseMap {
boolean terminal;
int slop; // valid if terminal == true and phraseHighlight == true
float boost; // valid if terminal == true
int termOrPhraseNumber; // valid if terminal == true
FieldQuery fieldQuery;
Map subMap = new HashMap<>();
public QueryPhraseMap(FieldQuery fieldQuery) {
this.fieldQuery = fieldQuery;
}
void addTerm(Term term, float boost) {
QueryPhraseMap map = getOrNewMap(subMap, term.text());
map.markTerminal(boost);
}
private QueryPhraseMap getOrNewMap(Map subMap, String term) {
QueryPhraseMap map = subMap.get(term);
if (map == null) {
map = new QueryPhraseMap(fieldQuery);
subMap.put(term, map);
}
return map;
}
void add(Query query, IndexReader reader) {
float boost = 1f;
while (query instanceof BoostQuery) {
BoostQuery bq = (BoostQuery) query;
query = bq.getQuery();
boost = bq.getBoost();
}
if (query instanceof TermQuery) {
addTerm(((TermQuery) query).getTerm(), boost);
} else if (query instanceof PhraseQuery) {
PhraseQuery pq = (PhraseQuery) query;
Term[] terms = pq.getTerms();
Map map = subMap;
QueryPhraseMap qpm = null;
for (Term term : terms) {
qpm = getOrNewMap(map, term.text());
map = qpm.subMap;
}
qpm.markTerminal(pq.getSlop(), boost);
} else
throw new RuntimeException("query \"" + query.toString() + "\" must be flatten first.");
}
public QueryPhraseMap getTermMap(String term) {
return subMap.get(term);
}
private void markTerminal(float boost) {
markTerminal(0, boost);
}
private void markTerminal(int slop, float boost) {
this.terminal = true;
this.slop = slop;
this.boost = boost;
this.termOrPhraseNumber = fieldQuery.nextTermOrPhraseNumber();
}
public boolean isTerminal() {
return terminal;
}
public int getSlop() {
return slop;
}
public float getBoost() {
return boost;
}
public int getTermOrPhraseNumber() {
return termOrPhraseNumber;
}
public QueryPhraseMap searchPhrase(final List phraseCandidate) {
QueryPhraseMap currMap = this;
for (TermInfo ti : phraseCandidate) {
currMap = currMap.subMap.get(ti.getText());
if (currMap == null) return null;
}
return currMap.isValidTermOrPhrase(phraseCandidate) ? currMap : null;
}
public boolean isValidTermOrPhrase(final List phraseCandidate) {
// check terminal
if (!terminal) return false;
// if the candidate is a term, it is valid
if (phraseCandidate.size() == 1) return true;
// else check whether the candidate is valid phrase
// compare position-gaps between terms to slop
int pos = phraseCandidate.get(0).getPosition();
for (int i = 1; i < phraseCandidate.size(); i++) {
int nextPos = phraseCandidate.get(i).getPosition();
if (Math.abs(nextPos - pos - 1) > slop) return false;
pos = nextPos;
}
return true;
}
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy