ClearNlpLemmatizer.java

/*
 * Copyright 2012
 * 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.clearnlp;

import static org.apache.uima.fit.util.JCasUtil.select;
import static org.apache.uima.fit.util.JCasUtil.selectCovered;

import java.io.InputStream;
import java.util.List;

import org.apache.uima.UimaContext;
import org.apache.uima.analysis_engine.AnalysisEngineProcessException;
import org.apache.uima.fit.component.JCasAnnotator_ImplBase;
import org.apache.uima.fit.descriptor.ConfigurationParameter;
import org.apache.uima.fit.descriptor.TypeCapability;
import org.apache.uima.jcas.JCas;
import org.apache.uima.resource.ResourceInitializationException;

import com.clearnlp.component.AbstractComponent;
import com.clearnlp.component.morph.DefaultMPAnalyzer;
import com.clearnlp.component.morph.EnglishMPAnalyzer;
import com.clearnlp.dependency.DEPNode;
import com.clearnlp.dependency.DEPTree;

import de.tudarmstadt.ukp.dkpro.core.api.parameter.ComponentParameters;
import de.tudarmstadt.ukp.dkpro.core.api.resources.CasConfigurableProviderBase;
import de.tudarmstadt.ukp.dkpro.core.api.resources.ModelProviderBase;
import de.tudarmstadt.ukp.dkpro.core.api.segmentation.type.Lemma;
import de.tudarmstadt.ukp.dkpro.core.api.segmentation.type.Sentence;
import de.tudarmstadt.ukp.dkpro.core.api.segmentation.type.Token;

/**
 * Lemmatizer using Clear NLP.
 *
 */
@TypeCapability(
		inputs = {
				"de.tudarmstadt.ukp.dkpro.core.api.segmentation.type.Sentence",
				"de.tudarmstadt.ukp.dkpro.core.api.segmentation.type.Token",
				"de.tudarmstadt.ukp.dkpro.core.api.lexmorph.type.pos.POS"
		},
		outputs = {
				"de.tudarmstadt.ukp.dkpro.core.api.segmentation.type.Lemma"
		}
)
public class ClearNlpLemmatizer
	extends JCasAnnotator_ImplBase
{

    /**
     * Use this language instead of the document language to resolve the model.
     */
    public static final String PARAM_LANGUAGE = ComponentParameters.PARAM_LANGUAGE;
    @ConfigurationParameter(name = PARAM_LANGUAGE, mandatory = false, defaultValue="en")
    protected String language;

    /**
     * Override the default variant used to locate the model.
     */
    public static final String PARAM_VARIANT = ComponentParameters.PARAM_VARIANT;
    @ConfigurationParameter(name = PARAM_VARIANT, mandatory = false)
    protected String variant;

    /**
     * Load the model from this location instead of locating the model automatically.
     */
    public static final String PARAM_MODEL_LOCATION = ComponentParameters.PARAM_MODEL_LOCATION;
    @ConfigurationParameter(name = PARAM_MODEL_LOCATION, mandatory = false)
    protected String modelLocation;

    private CasConfigurableProviderBase<AbstractComponent> modelProvider;

    @Override
    public void initialize(UimaContext aContext)
        throws ResourceInitializationException
    {
        super.initialize(aContext);

        modelProvider = new ModelProviderBase<AbstractComponent>(this, "clearnlp", "lemma")
        {
            @Override
            protected AbstractComponent produceResource(InputStream aStream)
                throws Exception
            {
                String lang = getAggregatedProperties().getProperty(LANGUAGE);
                AbstractComponent lemmatizer;
                if(lang.equals("en")){
                    lemmatizer = new EnglishMPAnalyzer(aStream);
                }else{
                    lemmatizer = new DefaultMPAnalyzer();
                }
                return lemmatizer;
            }
        };
    }

	@Override
	public void process(JCas aJCas)
		throws AnalysisEngineProcessException
	{

	    modelProvider.configure(aJCas.getCas());
		AbstractComponent analyzer = modelProvider.getResource();

		// Iterate over all sentences
		for (Sentence sentence : select(aJCas, Sentence.class)) {
			List<Token> tokens = selectCovered(aJCas, Token.class, sentence);

			DEPTree tree = new DEPTree();

			// Generate input format required by analyzer
			for (int i = 0; i < tokens.size(); i++) {
				Token t = tokens.get(i);
				DEPNode node = new DEPNode(i+1, tokens.get(i).getCoveredText());
				node.pos = t.getPos().getPosValue();
				tree.add(node);
			}

			analyzer.process(tree);

			int i = 0;
			for (Token t : tokens) {
				DEPNode node = tree.get(i+1);
                String lemmaString = node.lemma;
                if (lemmaString == null) {
                    lemmaString = t.getCoveredText();
                }
				Lemma l = new Lemma(aJCas, t.getBegin(), t.getEnd());
				l.setValue(lemmaString);
				l.addToIndexes();

				t.setLemma(l);
				i++;
			}
		}
	}
}