de.tuberlin.dima.cuttlefish.preprocessing.indexing.Indexer.java Source code

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Here is the source code for de.tuberlin.dima.cuttlefish.preprocessing.indexing.Indexer.java

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/*
 * Copyright (C) 2013 Database Systems and Information Management Group,
 * TU Berlin
 *
 * cuttlefish is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2 of the License,
 * or (at your option) any later version.
 *
 * cuttlefish 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with cuttlefish; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */

package de.tuberlin.dima.cuttlefish.preprocessing.indexing;

import de.tuberlin.dima.cuttlefish.preprocessing.NewsItem;
import de.tuberlin.dima.cuttlefish.preprocessing.parsing.NewsItemExtractor;
import de.tuberlin.dima.cuttlefish.preprocessing.parsing.NewsItemProcessor;
import org.apache.lucene.analysis.Analyzer;
/*
 * Copyright (C) 2013 Database Systems and Information Management Group,
 * TU Berlin
 *
 * cuttlefish is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published
 * by the Free Software Foundation; either version 2 of the License,
 * or (at your option) any later version.
 *
 * cuttlefish 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
 * General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with cuttlefish; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307
 * USA
 */

import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.SimpleFSDirectory;
import org.apache.lucene.util.Version;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.File;
import java.io.IOException;
import java.util.concurrent.atomic.AtomicInteger;

public class Indexer {

    private final NewsItemExtractor newsItemExtractor;
    private final FeatureExtraction featureExtraction;

    private static final Logger log = LoggerFactory.getLogger(Indexer.class);

    public Indexer(NewsItemExtractor newsItemExtractor, FeatureExtraction featureExtraction) {
        this.newsItemExtractor = newsItemExtractor;
        this.featureExtraction = featureExtraction;
    }

    public void index(File indexDir) throws Exception {
        Directory index = new SimpleFSDirectory(indexDir);
        Analyzer analyzer = featureExtraction.analyzerToUse();
        IndexWriterConfig config = new IndexWriterConfig(Version.LUCENE_42, analyzer);
        final IndexWriter writer = new IndexWriter(index, config);

        final AtomicInteger numDocsIndexed = new AtomicInteger(0);

        try {

            newsItemExtractor.extract(new NewsItemProcessor() {
                @Override
                public void process(NewsItem newsItem) {

                    try {
                        writer.addDocument(featureExtraction.asDocument(newsItem));
                        int numDocs = numDocsIndexed.incrementAndGet();
                        if (numDocs % 100 == 0) {
                            log.info("Indexed {} news articles", numDocs);
                        }

                    } catch (IOException e) {
                        log.error("Failed to index news item", e);
                    }
                }
            });

        } finally {
            writer.close(true);
        }

        log.info("Indexed {} news articles", numDocsIndexed.get());
    }

}