DfStore.java

/*
 * Copyright 2013
 * Ubiquitous Knowledge Processing (UKP) Lab
 * Technische Universität Darmstadt
 *
 * 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 language governing permissions and
 * limitations under the License.
 */
package de.tudarmstadt.ukp.dkpro.core.frequency.tfidf.model;

import java.io.Serializable;
import java.util.Set;
import java.util.TreeSet;

import de.tudarmstadt.ukp.dkpro.core.frequency.tfidf.TfidfAnnotator;
import de.tudarmstadt.ukp.dkpro.core.frequency.tfidf.TfidfConsumer;
import de.tudarmstadt.ukp.dkpro.core.frequency.tfidf.util.FreqDist;

/**
 * Container that stores the document frequency and additional data in a collection of documents. To
 * be filled and serialized by {@link TfidfConsumer} and deserialized and used by
 * {@link TfidfAnnotator}.
 * 
 */
public class DfStore
    implements DfModel, Serializable
{
    private static final long serialVersionUID = -7052868467568275617L;

    private final FreqDist<String> df;
    private String featurePath;
    private int documentCount = 0;
    private Set<String> termsInThisDocument;
    private final boolean lowercase;

    public DfStore()
    {
        df = new FreqDist<String>();
        lowercase = false;
    }

    public DfStore(String featurePath, boolean convertToLowercase)
    {
        df = new FreqDist<String>();
        this.featurePath = featurePath;
        this.lowercase = convertToLowercase;
    }

    /**
     * Call this method when starting processing a new document.
     */
    public void registerNewDocument()
    {
        documentCount++;
        termsInThisDocument = new TreeSet<String>();
    }

    public void countTerm(String term)
    {
        termsInThisDocument.add(term);
    }

    /**
     * Call this method when processing of document is over.
     */
    public void closeCurrentDocument()
    {
        df.count(termsInThisDocument);
        termsInThisDocument = null;
    }

    @Override
    public int getDf(String term)
    {
        return df.getCount(term);
    }

    @Override
    public int getDocumentCount()
    {
        return documentCount;
    }

    @Override
    public String getFeaturePath()
    {
        return featurePath;
    }

    @Override
    public boolean getLowercase()
    {
        return lowercase;
    }

}