CavalliumDBEngine/src/main/java/it/cavallium/dbengine/lucene/similarity/NGramSimilarity.java
2021-02-04 22:42:57 +01:00

55 lines
1.8 KiB
Java

/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* 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
*
* 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 specific language governing permissions and
* limitations under the License.
*/
package it.cavallium.dbengine.lucene.similarity;
import org.apache.lucene.search.similarities.ClassicSimilarity;
import org.apache.lucene.search.similarities.Similarity;
import org.novasearch.lucene.search.similarities.BM25Similarity;
import org.novasearch.lucene.search.similarities.BM25Similarity.BM25Model;
public class NGramSimilarity {
private NGramSimilarity() {
}
public static Similarity classic() {
var instance = new ClassicSimilarity();
instance.setDiscountOverlaps(false);
return instance;
}
public static Similarity bm25(BM25Model model) {
var instance = new BM25Similarity(model);
instance.setDiscountOverlaps(false);
return instance;
}
public static Similarity bm15(BM25Model model) {
var instance = new BM25Similarity(1.2f, 0.0f, 0.5f, model);
instance.setDiscountOverlaps(false);
return instance;
}
public static Similarity bm11(BM25Model model) {
var instance = new BM25Similarity(1.2f, 1.0f, 0.5f, model);
instance.setDiscountOverlaps(false);
return instance;
}
}