X-Git-Url: https://git.mdrn.pl/pylucene.git/blobdiff_plain/a2e61f0c04805cfcb8706176758d1283c7e3a55c..aaeed5504b982cf3545252ab528713250aa33eed:/lucene-java-3.4.0/lucene/contrib/queries/src/java/org/apache/lucene/search/BoostingQuery.java diff --git a/lucene-java-3.4.0/lucene/contrib/queries/src/java/org/apache/lucene/search/BoostingQuery.java b/lucene-java-3.4.0/lucene/contrib/queries/src/java/org/apache/lucene/search/BoostingQuery.java deleted file mode 100644 index 104e2b2..0000000 --- a/lucene-java-3.4.0/lucene/contrib/queries/src/java/org/apache/lucene/search/BoostingQuery.java +++ /dev/null @@ -1,127 +0,0 @@ -package org.apache.lucene.search; - -/** - * 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. - */ - -import java.io.IOException; - -import org.apache.lucene.index.IndexReader; -import org.apache.lucene.search.BooleanQuery; -import org.apache.lucene.search.DefaultSimilarity; -import org.apache.lucene.search.Query; -import org.apache.lucene.search.Searcher; -import org.apache.lucene.search.Similarity; -/** - * The BoostingQuery class can be used to effectively demote results that match a given query. - * Unlike the "NOT" clause, this still selects documents that contain undesirable terms, - * but reduces their overall score: - * - * Query balancedQuery = new BoostingQuery(positiveQuery, negativeQuery, 0.01f); - * In this scenario the positiveQuery contains the mandatory, desirable criteria which is used to - * select all matching documents, and the negativeQuery contains the undesirable elements which - * are simply used to lessen the scores. Documents that match the negativeQuery have their score - * multiplied by the supplied "boost" parameter, so this should be less than 1 to achieve a - * demoting effect - * - * This code was originally made available here: [WWW] http://marc.theaimsgroup.com/?l=lucene-user&m=108058407130459&w=2 - * and is documented here: http://wiki.apache.org/lucene-java/CommunityContributions - */ -public class BoostingQuery extends Query { - private float boost; // the amount to boost by - private Query match; // query to match - private Query context; // boost when matches too - - public BoostingQuery(Query match, Query context, float boost) { - this.match = match; - this.context = (Query)context.clone(); // clone before boost - this.boost = boost; - - this.context.setBoost(0.0f); // ignore context-only matches - } - - @Override - public Query rewrite(IndexReader reader) throws IOException { - BooleanQuery result = new BooleanQuery() { - - @Override - public Similarity getSimilarity(Searcher searcher) { - return new DefaultSimilarity() { - - @Override - public float coord(int overlap, int max) { - switch (overlap) { - - case 1: // matched only one clause - return 1.0f; // use the score as-is - - case 2: // matched both clauses - return boost; // multiply by boost - - default: - return 0.0f; - - } - } - }; - } - }; - - result.add(match, BooleanClause.Occur.MUST); - result.add(context, BooleanClause.Occur.SHOULD); - - return result; - } - - @Override - public int hashCode() { - final int prime = 31; - int result = 1; - result = prime * result + Float.floatToIntBits(boost); - result = prime * result + ((context == null) ? 0 : context.hashCode()); - result = prime * result + ((match == null) ? 0 : match.hashCode()); - return result; - } - - @Override - public boolean equals(Object obj) { - if (this == obj) - return true; - if (obj == null) - return false; - if (getClass() != obj.getClass()) - return false; - BoostingQuery other = (BoostingQuery) obj; - if (Float.floatToIntBits(boost) != Float.floatToIntBits(other.boost)) - return false; - if (context == null) { - if (other.context != null) - return false; - } else if (!context.equals(other.context)) - return false; - if (match == null) { - if (other.match != null) - return false; - } else if (!match.equals(other.match)) - return false; - return true; - } - - @Override - public String toString(String field) { - return match.toString(field) + "/" + context.toString(field); - } - }