de.lmu.ifi.dbs.elki.application.lucene.SimpleTextLoader.java Source code

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package de.lmu.ifi.dbs.elki.application.lucene;

/*
 This file is part of ELKI:
 Environment for Developing KDD-Applications Supported by Index-Structures
    
 Copyright (C) 2015
 Ludwig-Maximilians-Universitt Mnchen
 Lehr- und Forschungseinheit fr Datenbanksysteme
 ELKI Development Team
    
 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/>.
 */
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.net.URI;

import org.apache.lucene.analysis.standard.StandardAnalyzer;
import org.apache.lucene.document.Document;
import org.apache.lucene.document.Field;
import org.apache.lucene.index.IndexWriter;
import org.apache.lucene.index.IndexWriterConfig;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.FSDirectory;
import org.apache.lucene.util.Version;

import de.lmu.ifi.dbs.elki.application.AbstractApplication;
import de.lmu.ifi.dbs.elki.utilities.exceptions.AbortException;
import de.lmu.ifi.dbs.elki.utilities.io.FileUtil;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.OptionID;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameterization.Parameterization;
import de.lmu.ifi.dbs.elki.utilities.optionhandling.parameters.FileParameter;

/**
 * Simple text loader, assuming a folder with plain text files.
 *
 * @author Erich Schubert
 * @since 0.6.0
 */
public class SimpleTextLoader extends AbstractApplication {
    /**
     * Index and source folders.
     */
    File index, source;

    /**
     * Constructor.
     *
     * @param index Index folder
     * @param source Source folder
     */
    public SimpleTextLoader(File index, File source) {
        super();
        this.index = index;
        this.source = source;
    }

    @Override
    public void run() {
        try {
            final Directory dir = FSDirectory.open(index);
            IndexWriterConfig config = new IndexWriterConfig(Version.LUCENE_36,
                    new StandardAnalyzer(Version.LUCENE_36));
            IndexWriter writer = new IndexWriter(dir, config);

            final URI suri = source.toURI();
            for (File inf : source.listFiles()) {
                Document doc = new Document();
                String id = suri.relativize(inf.toURI()).getPath();
                String text = FileUtil.slurp(new FileInputStream(inf));
                doc.add(new Field("id", id, Field.Store.YES, Field.Index.NOT_ANALYZED));
                doc.add(new Field("contents", text, Field.Store.YES, Field.Index.ANALYZED));
                writer.addDocument(doc);
            }
            writer.close();
        } catch (IOException e) {
            throw new AbortException("I/O error in lucene.", e);
        }
    }

    public static class Parameterizer extends AbstractApplication.Parameterizer {
        /**
         * Parameter for the index to build.
         */
        public static final OptionID INDEX_ID = new OptionID("lucene.index", "Lucene index folder.");

        /**
         * Parameter for the source folder.
         */
        public static final OptionID SOURCE_ID = new OptionID("lucene.source", "Source file folder.");

        File index, source;

        @Override
        protected void makeOptions(Parameterization config) {
            super.makeOptions(config);
            FileParameter srcP = new FileParameter(SOURCE_ID, FileParameter.FileType.INPUT_FILE);
            if (config.grab(srcP)) {
                source = srcP.getValue();
            }
            FileParameter idxP = new FileParameter(INDEX_ID, FileParameter.FileType.OUTPUT_FILE);
            if (config.grab(idxP)) {
                index = idxP.getValue();
            }
        }

        @Override
        protected SimpleTextLoader makeInstance() {
            return new SimpleTextLoader(index, source);
        }
    }

    /**
     * Main method.
     *
     * @param args Command line parameters.
     */
    public static void main(String[] args) {
        runCLIApplication(SimpleTextLoader.class, args);
    }
}