X-Git-Url: https://git.mdrn.pl/pylucene.git/blobdiff_plain/a2e61f0c04805cfcb8706176758d1283c7e3a55c..aaeed5504b982cf3545252ab528713250aa33eed:/lucene-java-3.5.0/lucene/contrib/queries/src/java/org/apache/lucene/search/similar/MoreLikeThisQuery.java diff --git a/lucene-java-3.5.0/lucene/contrib/queries/src/java/org/apache/lucene/search/similar/MoreLikeThisQuery.java b/lucene-java-3.5.0/lucene/contrib/queries/src/java/org/apache/lucene/search/similar/MoreLikeThisQuery.java new file mode 100644 index 0000000..7499f5b --- /dev/null +++ b/lucene-java-3.5.0/lucene/contrib/queries/src/java/org/apache/lucene/search/similar/MoreLikeThisQuery.java @@ -0,0 +1,161 @@ +/* + * Created on 25-Jan-2006 + */ +package org.apache.lucene.search.similar; + +/** + * 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 java.util.Set; + +import org.apache.lucene.analysis.Analyzer; +import org.apache.lucene.index.IndexReader; +import org.apache.lucene.search.BooleanClause; +import org.apache.lucene.search.BooleanQuery; +import org.apache.lucene.search.Query; +import org.apache.lucene.search.similar.MoreLikeThis; + +import java.io.StringReader; + +/** + * A simple wrapper for MoreLikeThis for use in scenarios where a Query object + * is required eg in custom QueryParser extensions. At query.rewrite() time the + * reader is used to construct the actual MoreLikeThis object and obtain the + * real Query object. + */ +public class MoreLikeThisQuery extends Query { + + private String likeText; + private String[] moreLikeFields; + private Analyzer analyzer; + private String fieldName; + private float percentTermsToMatch = 0.3f; + private int minTermFrequency = 1; + private int maxQueryTerms = 5; + private Set stopWords = null; + private int minDocFreq = -1; + + /** @deprecated use {@link #MoreLikeThisQuery(String, String[], Analyzer, String)} instead. */ + @Deprecated + public MoreLikeThisQuery(String likeText, String[] moreLikeFields, Analyzer analyzer) { + this(likeText, moreLikeFields, analyzer, moreLikeFields[0]); + } + + /** + * @param moreLikeFields + */ + public MoreLikeThisQuery(String likeText, String[] moreLikeFields, Analyzer analyzer, String fieldName) { + this.likeText = likeText; + this.moreLikeFields = moreLikeFields; + this.analyzer = analyzer; + this.fieldName = fieldName; + } + + @Override + public Query rewrite(IndexReader reader) throws IOException { + MoreLikeThis mlt = new MoreLikeThis(reader); + + mlt.setFieldNames(moreLikeFields); + mlt.setAnalyzer(analyzer); + mlt.setMinTermFreq(minTermFrequency); + if (minDocFreq >= 0) { + mlt.setMinDocFreq(minDocFreq); + } + mlt.setMaxQueryTerms(maxQueryTerms); + mlt.setStopWords(stopWords); + BooleanQuery bq = (BooleanQuery) mlt.like(new StringReader(likeText), fieldName); + BooleanClause[] clauses = bq.getClauses(); + // make at least half the terms match + bq.setMinimumNumberShouldMatch((int) (clauses.length * percentTermsToMatch)); + return bq; + } + + /* + * (non-Javadoc) + * + * @see org.apache.lucene.search.Query#toString(java.lang.String) + */ + @Override + public String toString(String field) { + return "like:" + likeText; + } + + public float getPercentTermsToMatch() { + return percentTermsToMatch; + } + + public void setPercentTermsToMatch(float percentTermsToMatch) { + this.percentTermsToMatch = percentTermsToMatch; + } + + public Analyzer getAnalyzer() { + return analyzer; + } + + public void setAnalyzer(Analyzer analyzer) { + this.analyzer = analyzer; + } + + public String getLikeText() { + return likeText; + } + + public void setLikeText(String likeText) { + this.likeText = likeText; + } + + public int getMaxQueryTerms() { + return maxQueryTerms; + } + + public void setMaxQueryTerms(int maxQueryTerms) { + this.maxQueryTerms = maxQueryTerms; + } + + public int getMinTermFrequency() { + return minTermFrequency; + } + + public void setMinTermFrequency(int minTermFrequency) { + this.minTermFrequency = minTermFrequency; + } + + public String[] getMoreLikeFields() { + return moreLikeFields; + } + + public void setMoreLikeFields(String[] moreLikeFields) { + this.moreLikeFields = moreLikeFields; + } + + public Set getStopWords() { + return stopWords; + } + + public void setStopWords(Set stopWords) { + this.stopWords = stopWords; + } + + public int getMinDocFreq() { + return minDocFreq; + } + + public void setMinDocFreq(int minDocFreq) { + this.minDocFreq = minDocFreq; + } +}