com.textocat.textokit.postagger.PosTrimmer.java Source code

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Here is the source code for com.textocat.textokit.postagger.PosTrimmer.java

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/*
 *    Copyright 2015 Textocat
 *
 *    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 com.textocat.textokit.postagger;

import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Sets;
import com.textocat.textokit.commons.cas.FSUtils;
import com.textocat.textokit.morph.dictionary.resource.GramModel;
import com.textocat.textokit.morph.fs.Wordform;
import org.apache.uima.jcas.JCas;
import org.apache.uima.jcas.cas.StringArray;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.BitSet;
import java.util.Collection;
import java.util.Set;

/**
 * @author Rinat Gareev
 */
public class PosTrimmer {
    private final Logger log = LoggerFactory.getLogger(getClass());

    private GramModel gramModel;
    private Set<String> targetPosCategories;
    // derived
    private final BitSet targetBits; // DO NOT MODIFY!
    private Set<String> targetTags;

    public PosTrimmer(GramModel gramModel, String... targetPosCategories) {
        this(gramModel, ImmutableSet.copyOf(targetPosCategories));
    }

    public PosTrimmer(GramModel _gramModel, Set<String> _targetPosCategories) {
        this.gramModel = _gramModel;
        targetPosCategories = ImmutableSet.copyOf(_targetPosCategories);
        //
        targetBits = new BitSet();
        for (String cat : targetPosCategories) {
            BitSet catBS = gramModel.getGrammemWithChildrenBits(cat, true);
            if (catBS == null) {
                throw new IllegalStateException(String.format("Unknown grammeme %s", cat));
            }
            targetBits.or(catBS);
        }
        //
        targetTags = ImmutableSet.copyOf(gramModel.toGramSet(targetBits));
        log.info("PosTrimmer will retain following gram tags:\n{}", targetTags);
    }

    public void trim(JCas jCas, Wordform wf) {
        StringArray grammemsFS = wf.getGrammems();
        Set<String> grammems = Sets.newLinkedHashSet(FSUtils.toSet(grammemsFS));
        if (grammems.retainAll(targetTags)) {
            wf.setGrammems(FSUtils.toStringArray(jCas, grammems));
        }
    }

    public void trimInPlace(Collection<String> grammems) {
        grammems.retainAll(targetTags);
    }

    public void trimInPlace(BitSet posBits) {
        posBits.and(targetBits);
    }

    public Set<BitSet> trimAndMerge(Iterable<BitSet> srcCol) {
        Set<BitSet> result = Sets.newHashSet();
        for (final BitSet _posBits : srcCol) {
            BitSet posBits = (BitSet) _posBits.clone();
            trimInPlace(posBits);
            result.add(posBits);
        }
        return result;
    }
}