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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
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package org.elasticsearch.index.similarity;
import org.apache.lucene.search.similarities.PerFieldSimilarityWrapper;
import org.apache.lucene.search.similarities.Similarity;
import org.elasticsearch.common.inject.Inject;
import org.elasticsearch.common.settings.ImmutableSettings;
import org.elasticsearch.common.settings.Settings;
import org.elasticsearch.index.AbstractIndexComponent;
import org.elasticsearch.index.Index;
import org.elasticsearch.index.mapper.FieldMapper;
import org.elasticsearch.index.mapper.MapperService;
import org.elasticsearch.index.settings.IndexSettings;
/**
*
*/
public class SimilarityService extends AbstractIndexComponent {
private final SimilarityLookupService similarityLookupService;
private final MapperService mapperService;
private final Similarity perFieldSimilarity;
public SimilarityService(Index index) {
this(index, ImmutableSettings.Builder.EMPTY_SETTINGS);
}
public SimilarityService(Index index, Settings settings) {
this(index, settings, new SimilarityLookupService(index, settings), null);
}
@Inject
public SimilarityService(Index index, @IndexSettings Settings indexSettings,
final SimilarityLookupService similarityLookupService, final MapperService mapperService) {
super(index, indexSettings);
this.similarityLookupService = similarityLookupService;
this.mapperService = mapperService;
Similarity defaultSimilarity = similarityLookupService.similarity(SimilarityLookupService.DEFAULT_SIMILARITY).get();
// Expert users can configure the base type as being different to default, but out-of-box we use default.
Similarity baseSimilarity = (similarityLookupService.similarity("base") != null) ? similarityLookupService.similarity("base").get() :
defaultSimilarity;
this.perFieldSimilarity = (mapperService != null) ? new PerFieldSimilarity(defaultSimilarity, baseSimilarity, mapperService) :
defaultSimilarity;
}
public Similarity similarity() {
return perFieldSimilarity;
}
public SimilarityLookupService similarityLookupService() {
return similarityLookupService;
}
public MapperService mapperService() {
return mapperService;
}
static class PerFieldSimilarity extends PerFieldSimilarityWrapper {
private final Similarity defaultSimilarity;
private final Similarity baseSimilarity;
private final MapperService mapperService;
PerFieldSimilarity(Similarity defaultSimilarity, Similarity baseSimilarity, MapperService mapperService) {
this.defaultSimilarity = defaultSimilarity;
this.baseSimilarity = baseSimilarity;
this.mapperService = mapperService;
}
@Override
public float coord(int overlap, int maxOverlap) {
return baseSimilarity.coord(overlap, maxOverlap);
}
@Override
public float queryNorm(float valueForNormalization) {
return baseSimilarity.queryNorm(valueForNormalization);
}
@Override
public Similarity get(String name) {
FieldMapper mapper = mapperService.smartNameFieldMapper(name);
return (mapper != null && mapper.similarity() != null) ? mapper.similarity().get() : defaultSimilarity;
}
}
}