com.tilab.ca.sse.core.lucene.SimpleSearcher.java Source code

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Here is the source code for com.tilab.ca.sse.core.lucene.SimpleSearcher.java

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/*-
 * Copyright (C) 2012 Federico Cairo, Giuseppe Futia, Federico Benedetto.
 *
 * This program is free software: you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as
 * published by the Free Software Foundation, either version 3 of the
 * License, or (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */
package com.tilab.ca.sse.core.lucene;

import org.apache.lucene.document.Document;
import org.apache.lucene.index.IndexReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import org.apache.log4j.Logger;
import org.apache.lucene.document.Field;
import org.apache.lucene.index.Term;
import org.apache.lucene.search.IndexSearcher;
import org.apache.lucene.search.Query;
import org.apache.lucene.search.ScoreDoc;
import org.apache.lucene.search.TermQuery;
import org.apache.lucene.search.TopDocs;
import org.apache.lucene.search.TopScoreDocCollector;

public class SimpleSearcher {

    static Logger LOG = Logger.getLogger(SimpleSearcher.class.getName());

    LuceneManager luceneManager;
    IndexSearcher indexSearcher;
    IndexReader indexReader;

    public SimpleSearcher(LuceneManager lucene) throws IOException {
        LOG.debug("[constructor] - BEGIN");
        luceneManager = lucene;
        LOG.debug("Opening IndexSearcher for Lucene directory " + luceneManager.getLuceneCorpusIndexDirectory());
        indexReader = IndexReader.open(luceneManager.getLuceneCorpusIndexDirectory(), true);
        indexSearcher = new IndexSearcher(indexReader);
        LOG.debug("[constructor] - END");
    }

    public Document getFullDocument(int docNo) throws IOException {
        LOG.debug("[getFullDocument] - BEGIN");
        Document document;
        document = indexReader.document(docNo);
        LOG.debug("[getFullDocument] - END");
        return document;
    }

    public ScoreDoc[] getHits(Query query) throws IOException {
        LOG.debug("[getHits] - BEGIN");
        ScoreDoc[] result = getTopResults(query, luceneManager.getLimitForQueryResult());
        LOG.debug("[getHits] - END");
        return result;
    }

    private ScoreDoc[] getTopResults(Query query, int numResults) throws IOException {
        ScoreDoc[] hits;
        LOG.debug("[getTopResults] - BEGIN");
        TopScoreDocCollector collector = TopScoreDocCollector.create(numResults, false);
        indexSearcher.search(query, collector);
        hits = collector.topDocs().scoreDocs;
        LOG.debug("[getTopResults] - END");
        return hits;
    }

    public LuceneManager getLuceneManager() {
        return luceneManager;
    }

    public IndexSearcher getIndexSearcher() {
        return indexSearcher;
    }

    // Used by the Italian classifier
    public String getTitle(String uri) throws IOException {
        LOG.debug("[getTitle] - BEGIN");
        String result = "";
        String cleanUri = uri.replace("http://it.dbpedia.org/resource/", "").replace("http://dbpedia.org/resource/",
                "");
        Query q = new TermQuery(new Term("URI", cleanUri));
        TopDocs hits = indexSearcher.search(q, 1);
        if (hits.totalHits != 0) {
            int docId = hits.scoreDocs[0].doc;
            Document doc = getFullDocument(docId);
            if (doc.getField("TITLE").stringValue() != null) {
                result = doc.getField("TITLE").stringValue();
            }
        }
        LOG.debug("[getTitle] - END");
        return result;
    }

    // Used by the Italian classifier
    public String getImage(String uri) throws IOException {
        LOG.debug("[getImage] - BEGIN");
        String result = "";
        String cleanUri = uri.replace("http://it.dbpedia.org/resource/", "").replace("http://dbpedia.org/resource/",
                "");
        Query q = new TermQuery(new Term("URI", cleanUri));
        TopDocs hits = indexSearcher.search(q, 1);
        if (hits.totalHits != 0) {
            int docId = hits.scoreDocs[0].doc;
            Document doc = getFullDocument(docId);
            if (doc.getField("IMAGE") != null) {
                result = doc.getField("IMAGE").stringValue();
            }
        }
        LOG.debug("[getImage] - END");
        return result;
    }

    // Used by the Italian classifier
    public List getTypes(String uri) throws IOException {
        LOG.debug("[getTypes] - BEGIN");
        List<String> result = new ArrayList<>();
        String cleanUri = uri.replace("http://it.dbpedia.org/resource/", "").replace("http://dbpedia.org/resource/",
                "");
        Query q = new TermQuery(new Term("URI", cleanUri));
        TopDocs hits = getIndexSearcher().search(q, 1);
        if (hits.totalHits != 0) {
            int docId = hits.scoreDocs[0].doc;
            Document doc = getFullDocument(docId);
            Field[] types = doc.getFields("TYPE");
            for (Field type : types) {
                result.add(type.stringValue());
            }
        }
        LOG.debug("[getTypes] - END");
        return result;
    }

    // Used by the Italian classifier
    public String getSameAsFromEngToIta(String uri) throws IOException {
        LOG.debug("[getSameAsFromEngToIta] - BEGIN");
        String result = "";
        Query q = new TermQuery(new Term("SAMEAS", uri));
        TopDocs hits = getIndexSearcher().search(q, 1);
        if (hits.totalHits != 0) {
            int docId = hits.scoreDocs[0].doc;
            Document doc = getFullDocument(docId);
            if (doc.getField("URI") != null) {
                result = doc.getField("URI").stringValue();
            }
        }
        LOG.debug("[getSameAsFromEngToIta] - END");
        return result;
    }
}