org.elasticsearch.index.search.child.ParentIdsFilter Maven / Gradle / Ivy
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* the Apache License, Version 2.0 (the "License"); you may
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*
* http://www.apache.org/licenses/LICENSE-2.0
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package org.elasticsearch.index.search.child;
import org.apache.lucene.index.AtomicReaderContext;
import org.apache.lucene.index.DocsEnum;
import org.apache.lucene.index.Terms;
import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.search.DocIdSet;
import org.apache.lucene.search.DocIdSetIterator;
import org.apache.lucene.search.Filter;
import org.apache.lucene.util.Bits;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.FixedBitSet;
import org.elasticsearch.common.bytes.HashedBytesArray;
import org.elasticsearch.index.mapper.Uid;
import org.elasticsearch.index.mapper.internal.UidFieldMapper;
import java.io.IOException;
/**
* 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.
* 3) We can directly reference to values that originate from the id cache.
*/
final class ParentIdsFilter extends Filter {
private final BytesRef parentTypeBr;
private final Object[] keys;
private final boolean[] allocated;
private final Filter nonNestedDocsFilter;
public ParentIdsFilter(String parentType, Object[] keys, boolean[] allocated, Filter nonNestedDocsFilter) {
this.nonNestedDocsFilter = nonNestedDocsFilter;
this.parentTypeBr = new BytesRef(parentType);
this.keys = keys;
this.allocated = allocated;
}
@Override
public DocIdSet getDocIdSet(AtomicReaderContext context, Bits acceptDocs) throws IOException {
Terms terms = context.reader().terms(UidFieldMapper.NAME);
if (terms == null) {
return null;
}
TermsEnum termsEnum = terms.iterator(null);
BytesRef uidSpare = new BytesRef();
BytesRef idSpare = new BytesRef();
if (acceptDocs == null) {
acceptDocs = context.reader().getLiveDocs();
}
FixedBitSet nonNestedDocs = null;
if (nonNestedDocsFilter != null) {
nonNestedDocs = (FixedBitSet) nonNestedDocsFilter.getDocIdSet(context, acceptDocs);
}
DocsEnum docsEnum = null;
FixedBitSet result = null;
for (int i = 0; i < allocated.length; i++) {
if (!allocated[i]) {
continue;
}
idSpare.bytes = ((HashedBytesArray) keys[i]).toBytes();
idSpare.length = idSpare.bytes.length;
Uid.createUidAsBytes(parentTypeBr, idSpare, uidSpare);
if (termsEnum.seekExact(uidSpare)) {
int docId;
docsEnum = termsEnum.docs(acceptDocs, docsEnum, DocsEnum.FLAG_NONE);
if (result == null) {
docId = docsEnum.nextDoc();
if (docId != DocIdSetIterator.NO_MORE_DOCS) {
result = new FixedBitSet(context.reader().maxDoc());
} else {
continue;
}
} else {
docId = docsEnum.nextDoc();
if (docId == DocIdSetIterator.NO_MORE_DOCS) {
continue;
}
}
if (nonNestedDocs != null && !nonNestedDocs.get(docId)) {
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;
}
}