org.elasticsearch.index.fielddata.ordinals.SingletonGlobalOrdinalMapping Maven / Gradle / Ivy
Go to download
Show more of this group Show more artifacts with this name
Show all versions of elasticsearch Show documentation
Show all versions of elasticsearch Show documentation
Elasticsearch subproject :server
/*
* Copyright Elasticsearch B.V. and/or licensed to Elasticsearch B.V. under one
* or more contributor license agreements. Licensed under the Elastic License
* 2.0 and the Server Side Public License, v 1; you may not use this file except
* in compliance with, at your election, the Elastic License 2.0 or the Server
* Side Public License, v 1.
*/
package org.elasticsearch.index.fielddata.ordinals;
import org.apache.lucene.index.DocValues;
import org.apache.lucene.index.OrdinalMap;
import org.apache.lucene.index.SortedDocValues;
import org.apache.lucene.index.SortedSetDocValues;
import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.LongValues;
import java.io.IOException;
/**
* {@link SortedDocValues} implementation that returns global ordinals instead
* of segment ordinals.
*/
class SingletonGlobalOrdinalMapping extends SortedDocValues {
/**
* Build a {@link SortedDocValues singleton doc values} if possible
* Lots of other code tries to unwrap the singleton with
* {@link DocValues#unwrapSingleton} and it'll take a fast path if
* it gets a singleton. This'll return a singleton that can be
* unwrapped or {@code null} if the {@link OrdinalMap} and
* {@link SortedSetDocValues} aren't compatible with {@link SortedDocValues}.
*/
static SortedSetDocValues singletonIfPossible(OrdinalMap ordinalMap, SortedSetDocValues values, TermsEnum[] lookups, int segmentIndex) {
/*
* We can manage a singleton if the total value count
* fits in an `int` *and* the segment ords are a singleton.
* We need the first one just because SortedDocValues
* returns `int` instead of `long`
*/
if (ordinalMap.getValueCount() > Integer.MAX_VALUE) {
return null;
}
SortedDocValues singleton = DocValues.unwrapSingleton(values);
if (singleton == null) {
return null;
}
return DocValues.singleton(new SingletonGlobalOrdinalMapping(ordinalMap, singleton, lookups, segmentIndex));
}
private final SortedDocValues values;
private final OrdinalMap ordinalMap;
private final LongValues mapping;
private final TermsEnum[] lookups;
private SingletonGlobalOrdinalMapping(OrdinalMap ordinalMap, SortedDocValues values, TermsEnum[] lookups, int segmentIndex) {
this.values = values;
this.lookups = lookups;
this.ordinalMap = ordinalMap;
this.mapping = ordinalMap.getGlobalOrds(segmentIndex);
}
@Override
public int getValueCount() {
return (int) ordinalMap.getValueCount();
}
@Override
public int ordValue() throws IOException {
return (int) mapping.get(values.ordValue());
}
@Override
public boolean advanceExact(int target) throws IOException {
return values.advanceExact(target);
}
@Override
public BytesRef lookupOrd(int globalOrd) throws IOException {
final long segmentOrd = ordinalMap.getFirstSegmentOrd(globalOrd);
int readerIndex = ordinalMap.getFirstSegmentNumber(globalOrd);
lookups[readerIndex].seekExact(segmentOrd);
return lookups[readerIndex].term();
}
@Override
public int docID() {
return values.docID();
}
@Override
public int nextDoc() throws IOException {
return values.nextDoc();
}
@Override
public int advance(int target) throws IOException {
return values.advance(target);
}
@Override
public long cost() {
return values.cost();
}
}