MeCabWhiteSpacesTest.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.mecab;

import static org.apache.uima.fit.factory.AnalysisEngineFactory.createEngine;
import static org.apache.uima.fit.factory.CollectionReaderFactory.createReaderDescription;
import static org.junit.Assert.assertEquals;

import java.io.IOException;
import java.util.Collection;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import org.apache.uima.UIMAException;
import org.apache.uima.analysis_engine.AnalysisEngine;
import org.apache.uima.collection.CollectionReaderDescription;
import org.apache.uima.fit.pipeline.JCasIterable;
import org.apache.uima.fit.util.JCasUtil;
import org.apache.uima.jcas.JCas;
import org.junit.Test;

import de.tudarmstadt.ukp.dkpro.core.io.text.TextReader;
import de.tudarmstadt.ukp.dkpro.core.mecab.type.JapaneseToken;

/**
 * This test covers a case where mecab decides that a whitespace character is a
 * own token. The assumption for our wrapper is that a whitespace does not occur
 * as own token. This case leads to situations where the index breaks
 * <code>null</code> initialized annotations are created.
 */
public class MeCabWhiteSpacesTest {

    @Test
    public void sequenceOfWhitespacesAtEndOfFile() throws UIMAException, IOException {
        CollectionReaderDescription reader = createReaderDescription(
                TextReader.class, 
                TextReader.PARAM_SOURCE_LOCATION, "src/test/resources",
                TextReader.PARAM_LANGUAGE, "ja", 
                TextReader.PARAM_PATTERNS, "[+]EoFWithSequenceOfWhitespacesAndBlanks.txt");
        AnalysisEngine jTagger = createEngine(MeCabTagger.class);
        try {
            JCas jcas = new JCasIterable(reader).iterator().next();
            jTagger.process(jcas);
            Collection<JapaneseToken> tokens = JCasUtil.select(jcas, JapaneseToken.class);
            assertEquals(2, tokens.size());
            // access all tokens
            Iterator<JapaneseToken> iterator = tokens.iterator();
            while (iterator.hasNext()) {
                System.out.println(iterator.next().getCoveredText());
            }
        } finally {
            jTagger.destroy();
        }
    }

    @Test
    public void whitespaceBeforeToken() throws UIMAException, IOException {
        CollectionReaderDescription reader = createReaderDescription(
                TextReader.class, 
                TextReader.PARAM_SOURCE_LOCATION, "src/test/resources",
                TextReader.PARAM_LANGUAGE, "ja", 
                TextReader.PARAM_PATTERNS, new String[] { "[+]TokenPreceedingWhitespace.txt" });

        AnalysisEngine jTagger = createEngine(MeCabTagger.class);
        try {
            JCas jcas = new JCasIterable(reader).iterator().next();
            jTagger.process(jcas);
            Collection<JapaneseToken> tokens = JCasUtil.select(jcas, JapaneseToken.class);
            List<String> stringTokens = new LinkedList<String>();
            Iterator<JapaneseToken> iterator = tokens.iterator();
            while (iterator.hasNext()) {
                JapaneseToken next = iterator.next();
                stringTokens.add(next.getCoveredText());
            }
            assertEquals(6, stringTokens.size());
        } finally {
            jTagger.destroy();
        }
    }

    @Test
    public void whitespaceIsAnnotatedAsToken() throws UIMAException, IOException {
        CollectionReaderDescription reader = createReaderDescription(
                TextReader.class, 
                TextReader.PARAM_SOURCE_LOCATION, "src/test/resources",
                TextReader.PARAM_LANGUAGE, "ja", 
                TextReader.PARAM_PATTERNS, new String[] { "[+]WhiteSpaceAsToken.txt" });

        AnalysisEngine jTagger = createEngine(MeCabTagger.class);
        try {
            JCas jcas = new JCasIterable(reader).iterator().next();
            jTagger.process(jcas);
            Collection<JapaneseToken> tokens = JCasUtil.select(jcas, JapaneseToken.class);
            List<String> stringTokens = new LinkedList<String>();
            Iterator<JapaneseToken> iterator = tokens.iterator();
            while (iterator.hasNext()) {
                JapaneseToken next = iterator.next();
                stringTokens.add(next.getCoveredText());
            }
            assertEquals(59, stringTokens.size());
        } finally {
            jTagger.destroy();
        }
    }

}