* Licensed to the Apache Software Foundation (ASF) under one

* or more contributor license agreements.  See the NOTICE file

* distributed with this work for additional information

* regarding copyright ownership.  The ASF licenses this file

* to you 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.

*/

  private static final String TOKEN_ANNOTATION_NAME = "org.apache.uima.TokenAnnotation";

  private static final String TOKEN_ANNOTATION_STEM_FEATURE_NAME = "stem";

  private Type tokenAnnotation;

  private Feature tokenAnnotationStemmFeature;

  private Logger logger;

  private HashMap stemmers;

  private static final Object[] emptyArgs = new Object[0];

  /*

   * (non-Javadoc)

   *

   * @see org.apache.uima.analysis_engine.annotator.JTextAnnotator#process(org.apache.uima.jcas.impl.JCas,

   *      org.apache.uima.analysis_engine.ResultSpecification)

   */

  public void process(JCas aJCas, ResultSpecification aResultSpec) throws AnnotatorProcessException {

    this.logger.log(Level.INFO, "Snowball annotator starts processing");

    // get get stemmer for the document language

    String language = new Language(aJCas.getDocumentLanguage()).getLanguagePart();

    SnowballProgram stemmer = (SnowballProgram) this.stemmers.get(language);

    // create stemms if stemmer for the current document language is available

    if (stemmer != null) {

      // get stem() method from stemmer

      Method stemmerStemMethod;

      try {

        stemmerStemMethod = stemmer.getClass().getMethod("stem", new Class[0]);

      } catch (Exception ex) {

        throw new AnnotatorProcessException(ex);

      }

      // iterate over all token annotations and add stem if available

      FSIterator tokenIterator = aJCas.getCas().getAnnotationIndex(this.tokenAnnotation).iterator();

      while (tokenIterator.hasNext()) {

        // get token content

        AnnotationFS annot = (AnnotationFS) tokenIterator.next();

        String span = annot.getCoveredText();

        // set annotation content and call stemmer

        try {

          stemmer.setCurrent(span);

          stemmerStemMethod.invoke(stemmer, emptyArgs);

        } catch (Exception ex) {

          throw new AnnotatorProcessException(ex);

        }

        // get stemmer result and set annotation feature

        annot.setStringValue(this.tokenAnnotationStemmFeature, stemmer.getCurrent());

      }

    }

    this.logger.log(Level.INFO, "Snowball annotator processing finished");

  }

  /* (non-Javadoc)

   * @see org.apache.uima.analysis_engine.annotator.Annotator_ImplBase#initialize(org.apache.uima.analysis_engine.annotator.AnnotatorContext)

   */

  public void initialize(AnnotatorContext aContext) throws AnnotatorInitializationException,

          AnnotatorConfigurationException {

    // initialize logger

    try {

      this.logger = aContext.getLogger();

      // initialize stemmers

      this.stemmers = new HashMap();

      this.stemmers.put("da", new danishStemmer());

      this.stemmers.put("nl", new dutchStemmer());

      this.stemmers.put("en", new englishStemmer());

      this.stemmers.put("fi", new finnishStemmer());

      this.stemmers.put("fr", new frenchStemmer());

      this.stemmers.put("de", new germanStemmer());

      this.stemmers.put("hu", new hungarianStemmer());

      this.stemmers.put("it", new italianStemmer());

      this.stemmers.put("no", new norwegianStemmer());

      this.stemmers.put("pt", new portugueseStemmer());

      this.stemmers.put("ru", new russianStemmer());

      this.stemmers.put("es", new spanishStemmer());

      this.stemmers.put("sw", new swedishStemmer());

    } catch (Exception ex) {

      throw new AnnotatorInitializationException(ex);

    }

    this.logger.log(Level.INFO, "Snowball annotator successfully initialized");

  }

  /* (non-Javadoc)

   * @see org.apache.uima.analysis_engine.annotator.Annotator_ImplBase#typeSystemInit(org.apache.uima.cas.TypeSystem)

   */

  public void typeSystemInit(TypeSystem aTypeSystem) throws AnnotatorInitializationException,

          AnnotatorConfigurationException {

    // initialize cas token type

    this.tokenAnnotation = aTypeSystem.getType(TOKEN_ANNOTATION_NAME);

    this.tokenAnnotationStemmFeature = aTypeSystem.getFeatureByFullName(TOKEN_ANNOTATION_NAME

            + TypeSystem.FEATURE_SEPARATOR + TOKEN_ANNOTATION_STEM_FEATURE_NAME);

    this.logger.log(Level.INFO, "Snowball annotator typesystem initialized");

  }

}