org.trypticon.luceneupgrader.lucene5.internal.lucene.search.RandomAccessWeight Maven / Gradle / Ivy
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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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* Unless required by applicable law or agreed to in writing, software
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* See the License for the specific language governing permissions and
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package org.trypticon.luceneupgrader.lucene5.internal.lucene.search;
import java.io.IOException;
import org.trypticon.luceneupgrader.lucene5.internal.lucene.index.LeafReaderContext;
import org.trypticon.luceneupgrader.lucene5.internal.lucene.util.Bits;
import org.trypticon.luceneupgrader.lucene5.internal.lucene.util.Bits.MatchNoBits;
/**
* Base class to build {@link Weight}s that are based on random-access
* structures such as live docs or doc values. Such weights return a
* {@link Scorer} which consists of an approximation that matches
* everything, and a confirmation phase that first checks live docs and
* then the {@link Bits} returned by {@link #getMatchingDocs(LeafReaderContext)}.
* @lucene.internal
*/
public abstract class RandomAccessWeight extends ConstantScoreWeight {
/** Sole constructor. */
protected RandomAccessWeight(Query query) {
super(query);
}
/**
* Return a {@link Bits} instance representing documents that match this
* weight on the given context. A return value of {@code null} indicates
* that no documents matched.
* Note: it is not needed to care about live docs as they will be checked
* before the returned bits.
*/
protected abstract Bits getMatchingDocs(LeafReaderContext context) throws IOException;
@Override
public final Scorer scorer(LeafReaderContext context) throws IOException {
final Bits matchingDocs = getMatchingDocs(context);
if (matchingDocs == null || matchingDocs instanceof MatchNoBits) {
return null;
}
final DocIdSetIterator approximation = DocIdSetIterator.all(context.reader().maxDoc());
final TwoPhaseIterator twoPhase = new TwoPhaseIterator(approximation) {
@Override
public boolean matches() throws IOException {
final int doc = approximation.docID();
return matchingDocs.get(doc);
}
@Override
public float matchCost() {
return 10; // TODO: use some cost of matchingDocs
}
};
return new ConstantScoreScorer(this, score(), twoPhase);
}
}