com.mathworks.xzheng.searching.Explainer.java Source code

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Here is the source code for com.mathworks.xzheng.searching.Explainer.java

Source

package com.mathworks.xzheng.searching;

/**
 * Copyright Manning Publications Co.
 *
 * Licensed 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 lan      
*/

import java.io.File;

import org.apache.lucene.analysis.core.SimpleAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.index.DirectoryReader;
import org.apache.lucene.queryparser.classic.QueryParser;
import org.apache.lucene.search.Explanation;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.Version;

// From chapter 3
public class Explainer {
    public static void main(String[] args) throws Exception {
        if (args.length != 2) {
            System.err.println("Usage: Explainer <index dir> <query>");
            System.exit(1);
        }

        String indexDir = args[0];
        String queryExpression = args[1];

        Directory directory = FSDirectory.open(new File(indexDir));
        QueryParser parser = new QueryParser(Version.LUCENE_46, "contents", new SimpleAnalyzer(Version.LUCENE_46));
        Query query = parser.parse(queryExpression);

        System.out.println("Query: " + queryExpression);

        IndexSearcher searcher = new IndexSearcher(DirectoryReader.open(directory));
        TopDocs topDocs = searcher.search(query, 10);

        for (ScoreDoc match : topDocs.scoreDocs) {
            Explanation explanation = searcher.explain(query, match.doc); //#A

            System.out.println("----------");
            Document doc = searcher.doc(match.doc);
            System.out.println(doc.get("title"));
            System.out.println(explanation.toString()); //#B
        }

        directory.close();
    }
}
/*
#A Generate Explanation
#B Output Explanation
*/