de.tuberlin.dima.cuttlefish.preprocessing.vectorization.FeatureDictionary.java Source code

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Here is the source code for de.tuberlin.dima.cuttlefish.preprocessing.vectorization.FeatureDictionary.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.vectorization;

import com.google.common.collect.Maps;
import com.google.common.io.Closeables;

import java.io.BufferedWriter;
import java.io.File;
import java.io.FileWriter;
import java.io.IOException;
import java.util.Map;
import java.util.SortedMap;
import java.util.TreeMap;

public class FeatureDictionary {

    private final Map<String, Map<String, Integer>> textFeatureOffsets = Maps.newHashMap();

    private int index = 0;

    public void addTextFeature(String field, String term) {
        if (!textFeatureOffsets.containsKey(field)) {
            textFeatureOffsets.put(field, Maps.<String, Integer>newHashMap());
        }
        textFeatureOffsets.get(field).put(term, index);
        index++;
    }

    public int index(String field, String term) {
        return textFeatureOffsets.get(field).get(term);
    }

    public int numFeatures() {
        return index;
    }

    public void writeToFile(File file) throws IOException {
        SortedMap<Integer, String> features = new TreeMap<Integer, String>();

        for (Map.Entry<String, Map<String, Integer>> fieldEntry : textFeatureOffsets.entrySet()) {
            String field = fieldEntry.getKey();
            for (Map.Entry<String, Integer> featureWithOffset : fieldEntry.getValue().entrySet()) {
                features.put(featureWithOffset.getValue(), field + "=" + featureWithOffset.getKey());
            }
        }

        BufferedWriter writer = null;

        try {
            writer = new BufferedWriter(new FileWriter(file));

            for (Map.Entry<Integer, String> feature : features.entrySet()) {
                writer.write(String.valueOf(feature.getKey()));
                writer.write(" ");
                writer.write(feature.getValue());
                writer.newLine();
            }

        } finally {
            Closeables.close(writer, true);
        }
    }

}