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* this work for additional information regarding copyright
* ownership. Elasticsearch 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.elasticsearch.index.search.child;
import org.apache.lucene.index.DocsEnum;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.SortedDocValues;
import org.apache.lucene.index.Term;
import org.apache.lucene.index.Terms;
import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.queries.TermFilter;
import org.apache.lucene.search.DocIdSet;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.Filter;
import org.apache.lucene.search.join.BitDocIdSetFilter;
import org.apache.lucene.util.BitDocIdSet;
import org.apache.lucene.util.BitSet;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.BytesRefBuilder;
import org.apache.lucene.util.FixedBitSet;
import org.apache.lucene.util.LongBitSet;
import org.apache.lucene.util.SparseFixedBitSet;
import org.elasticsearch.common.lease.Releasables;
import org.elasticsearch.common.lucene.search.AndFilter;
import org.elasticsearch.common.util.BytesRefHash;
import org.elasticsearch.common.util.LongHash;
import org.elasticsearch.index.mapper.Uid;
import org.elasticsearch.index.mapper.internal.UidFieldMapper;
import org.elasticsearch.search.internal.SearchContext;
import java.io.IOException;
import java.util.Arrays;
import java.util.List;
/**
* Advantages over using this filter over Lucene's TermsFilter in the parent child context:
* 1) Don't need to copy all values over to a list from the id cache and then
* copy all the ids values over to one continuous byte array. Should save a lot of of object creations and gcs..
* 2) We filter docs by one field only.
*/
final class ParentIdsFilter extends Filter {
static Filter createShortCircuitFilter(BitDocIdSetFilter nonNestedDocsFilter, SearchContext searchContext,
String parentType, SortedDocValues globalValues,
LongBitSet parentOrds, long numFoundParents) {
if (numFoundParents == 1) {
BytesRef id = globalValues.lookupOrd((int) parentOrds.nextSetBit(0));
if (nonNestedDocsFilter != null) {
List<Filter> filters = Arrays.asList(
new TermFilter(new Term(UidFieldMapper.NAME, Uid.createUidAsBytes(parentType, id))),
nonNestedDocsFilter
);
return new AndFilter(filters);
} else {
return new TermFilter(new Term(UidFieldMapper.NAME, Uid.createUidAsBytes(parentType, id)));
}
} else {
BytesRefHash parentIds= null;
boolean constructed = false;
try {
parentIds = new BytesRefHash(numFoundParents, searchContext.bigArrays());
for (long parentOrd = parentOrds.nextSetBit(0); parentOrd != -1; parentOrd = parentOrds.nextSetBit(parentOrd + 1)) {
parentIds.add(globalValues.lookupOrd((int) parentOrd));
}
constructed = true;
} finally {
if (!constructed) {
Releasables.close(parentIds);
}
}
searchContext.addReleasable(parentIds, SearchContext.Lifetime.COLLECTION);
return new ParentIdsFilter(parentType, nonNestedDocsFilter, parentIds);
}
}
static Filter createShortCircuitFilter(BitDocIdSetFilter nonNestedDocsFilter, SearchContext searchContext,
String parentType, SortedDocValues globalValues,
LongHash parentIdxs, long numFoundParents) {
if (numFoundParents == 1) {
BytesRef id = globalValues.lookupOrd((int) parentIdxs.get(0));
if (nonNestedDocsFilter != null) {
List<Filter> filters = Arrays.asList(
new TermFilter(new Term(UidFieldMapper.NAME, Uid.createUidAsBytes(parentType, id))),
nonNestedDocsFilter
);
return new AndFilter(filters);
} else {
return new TermFilter(new Term(UidFieldMapper.NAME, Uid.createUidAsBytes(parentType, id)));
}
} else {
BytesRefHash parentIds = null;
boolean constructed = false;
try {
parentIds = new BytesRefHash(numFoundParents, searchContext.bigArrays());
for (int id = 0; id < parentIdxs.size(); id++) {
parentIds.add(globalValues.lookupOrd((int) parentIdxs.get(id)));
}
constructed = true;
} finally {
if (!constructed) {
Releasables.close(parentIds);
}
}
searchContext.addReleasable(parentIds, SearchContext.Lifetime.COLLECTION);
return new ParentIdsFilter(parentType, nonNestedDocsFilter, parentIds);
}
}
private final BytesRef parentTypeBr;
private final BitDocIdSetFilter nonNestedDocsFilter;
private final BytesRefHash parentIds;
private ParentIdsFilter(String parentType, BitDocIdSetFilter nonNestedDocsFilter, BytesRefHash parentIds) {
this.nonNestedDocsFilter = nonNestedDocsFilter;
this.parentTypeBr = new BytesRef(parentType);
this.parentIds = parentIds;
}
@Override
public DocIdSet getDocIdSet(LeafReaderContext context, Bits acceptDocs) throws IOException {
Terms terms = context.reader().terms(UidFieldMapper.NAME);
if (terms == null) {
return null;
}
TermsEnum termsEnum = terms.iterator(null);
BytesRefBuilder uidSpare = new BytesRefBuilder();
BytesRef idSpare = new BytesRef();
if (acceptDocs == null) {
acceptDocs = context.reader().getLiveDocs();
}
BitSet nonNestedDocs = null;
if (nonNestedDocsFilter != null) {
nonNestedDocs = nonNestedDocsFilter.getDocIdSet(context).bits();
}
DocsEnum docsEnum = null;
BitSet result = null;
int size = (int) parentIds.size();
for (int i = 0; i < size; i++) {
parentIds.get(i, idSpare);
BytesRef uid = Uid.createUidAsBytes(parentTypeBr, idSpare, uidSpare);
if (termsEnum.seekExact(uid)) {
int docId;
docsEnum = termsEnum.docs(acceptDocs, docsEnum, DocsEnum.FLAG_NONE);
if (result == null) {
docId = docsEnum.nextDoc();
if (docId != DocIdSetIterator.NO_MORE_DOCS) {
// very rough heuristic that tries to get an idea of the number of documents
// in the set based on the number of parent ids that we didn't find in this segment
final int expectedCardinality = size / (i + 1);
// similar heuristic to BitDocIdSet.Builder
if (expectedCardinality >= (context.reader().maxDoc() >>> 10)) {
result = new FixedBitSet(context.reader().maxDoc());
} else {
result = new SparseFixedBitSet(context.reader().maxDoc());
}
} else {
continue;
}
} else {
docId = docsEnum.nextDoc();
if (docId == DocIdSetIterator.NO_MORE_DOCS) {
continue;
}
}
if (nonNestedDocs != null) {
docId = nonNestedDocs.nextSetBit(docId);
}
result.set(docId);
assert docsEnum.advance(docId + 1) == DocIdSetIterator.NO_MORE_DOCS : "DocId " + docId + " should have been the last one but docId " + docsEnum.docID() + " exists.";
}
}
return result == null ? null : new BitDocIdSet(result);
}
}