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 * 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
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package org.apache.lucene.search;


import java.io.IOException;

import org.apache.lucene.index.DocValues;
import org.apache.lucene.index.IndexReader;
import org.apache.lucene.index.LeafReaderContext;
import org.apache.lucene.index.SortedSetDocValues;
import org.apache.lucene.index.Terms;
import org.apache.lucene.index.TermsEnum;
import org.apache.lucene.util.LongBitSet;

Rewrites MultiTermQueries into a filter, using DocValues for term enumeration.

This can be used to perform these queries against an unindexed docvalues field.

@lucene.experimental
/** * Rewrites MultiTermQueries into a filter, using DocValues for term enumeration. * <p> * This can be used to perform these queries against an unindexed docvalues field. * @lucene.experimental */
public final class DocValuesRewriteMethod extends MultiTermQuery.RewriteMethod { @Override public Query rewrite(IndexReader reader, MultiTermQuery query) { return new ConstantScoreQuery(new MultiTermQueryDocValuesWrapper(query)); } static class MultiTermQueryDocValuesWrapper extends Query { protected final MultiTermQuery query;
Wrap a MultiTermQuery as a Filter.
/** * Wrap a {@link MultiTermQuery} as a Filter. */
protected MultiTermQueryDocValuesWrapper(MultiTermQuery query) { this.query = query; } @Override public String toString(String field) { // query.toString should be ok for the filter, too, if the query boost is 1.0f return query.toString(field); } @Override public final boolean equals(final Object other) { return sameClassAs(other) && query.equals(((MultiTermQueryDocValuesWrapper) other).query); } @Override public final int hashCode() { return 31 * classHash() + query.hashCode(); }
Returns the field name for this query
/** Returns the field name for this query */
public final String getField() { return query.getField(); } @Override public void visit(QueryVisitor visitor) { if (visitor.acceptField(query.getField())) { visitor.getSubVisitor(BooleanClause.Occur.FILTER, query); } } @Override public Weight createWeight(IndexSearcher searcher, ScoreMode scoreMode, float boost) throws IOException { return new ConstantScoreWeight(this, boost) { @Override public Matches matches(LeafReaderContext context, int doc) throws IOException { final SortedSetDocValues fcsi = DocValues.getSortedSet(context.reader(), query.field); return MatchesUtils.forField(query.field, () -> DisjunctionMatchesIterator.fromTermsEnum(context, doc, query, query.field, getTermsEnum(fcsi))); } private TermsEnum getTermsEnum(SortedSetDocValues fcsi) throws IOException { return query.getTermsEnum(new Terms() { @Override public TermsEnum iterator() throws IOException { return fcsi.termsEnum(); } @Override public long getSumTotalTermFreq() { throw new UnsupportedOperationException(); } @Override public long getSumDocFreq() { throw new UnsupportedOperationException(); } @Override public int getDocCount() { throw new UnsupportedOperationException(); } @Override public long size() { return -1; } @Override public boolean hasFreqs() { return false; } @Override public boolean hasOffsets() { return false; } @Override public boolean hasPositions() { return false; } @Override public boolean hasPayloads() { return false; } }); } @Override public Scorer scorer(LeafReaderContext context) throws IOException { final SortedSetDocValues fcsi = DocValues.getSortedSet(context.reader(), query.field); TermsEnum termsEnum = getTermsEnum(fcsi); assert termsEnum != null; if (termsEnum.next() == null) { // no matching terms return null; } // fill into a bitset // Cannot use FixedBitSet because we require long index (ord): final LongBitSet termSet = new LongBitSet(fcsi.getValueCount()); do { long ord = termsEnum.ord(); if (ord >= 0) { termSet.set(ord); } } while (termsEnum.next() != null); return new ConstantScoreScorer(this, score(), scoreMode, new TwoPhaseIterator(fcsi) { @Override public boolean matches() throws IOException { for (long ord = fcsi.nextOrd(); ord != SortedSetDocValues.NO_MORE_ORDS; ord = fcsi.nextOrd()) { if (termSet.get(ord)) { return true; } } return false; } @Override public float matchCost() { return 3; // lookup in a bitset } }); } @Override public boolean isCacheable(LeafReaderContext ctx) { return DocValues.isCacheable(ctx, query.field); } }; } } @Override public boolean equals(Object other) { return other != null && getClass() == other.getClass(); } @Override public int hashCode() { return 641; } }