trunk/ruta-core/src/main/java/org/apache/uima/ruta/seed/DefaultSeeder.java

/*
 * 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.
 */

package org.apache.uima.ruta.seed;

import java.io.BufferedReader;
import java.io.StringReader;
import java.util.Collection;
import java.util.LinkedList;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

import org.apache.uima.cas.CAS;
import org.apache.uima.cas.CASException;
import org.apache.uima.cas.FSIterator;
import org.apache.uima.cas.Type;
import org.apache.uima.cas.text.AnnotationFS;
import org.apache.uima.jcas.JCas;
import org.apache.uima.ruta.type.MARKUP;
import org.apache.uima.ruta.type.TokenSeed;

public class DefaultSeeder implements RutaAnnotationSeeder {

  public static final String seedType = "org.apache.uima.ruta.type.TokenSeed";

  private final Pattern markupPattern = Pattern
          .compile("</?\\w+((\\s+\\w+(\\s*=\\s*(?:\".*?\"|'.*?'|[^'\">\\s]+))?)+\\s*|\\s*)/?>");

  public Type seed(String text, CAS cas) {
    Type result = null;
    JCas jCas = null;
    int size = 0;
    try {
      jCas = cas.getJCas();
      size = jCas.getAnnotationIndex(TokenSeed.type).size();
      result = jCas.getTypeSystem().getType(seedType);
    } catch (CASException e1) {
    }
    // do not apply seeding if there are already annotations of this seed type
    if (jCas == null || size != 0 || text == null) {
      return result;
    }
    BufferedReader reader = new BufferedReader(new StringReader(text));
    final SeedLexer sourceLexer = new SeedLexer(reader);
    sourceLexer.setJCas(jCas);
    AnnotationFS a = null;

    try {
      a = sourceLexer.yylex();
    } catch (Exception e) {
    }
    while (a != null) {
      cas.addFsToIndexes(a);
      try {
        a = sourceLexer.yylex();
      } catch (Exception e) {
      }
    }

    // FIXME: lexer rules for html markup won't work. Therrfore, those rules where removed in the
    // grammar and the functionality is included directly with regexp
    Matcher matcher = markupPattern.matcher(text);
    Collection<AnnotationFS> toRemove = new LinkedList<AnnotationFS>();
    while (matcher.find()) {
      int begin = matcher.start();
      int end = matcher.end();
      MARKUP markup = new MARKUP(jCas, begin, end);
      markup.addToIndexes();
      FSIterator<AnnotationFS> subiterator = cas.getAnnotationIndex(result).subiterator(markup);
      while (subiterator.isValid()) {
        AnnotationFS fs = subiterator.get();
        toRemove.add(fs);
        subiterator.moveToNext();
      }
    }
    for (AnnotationFS each : toRemove) {
      cas.removeFsFromIndexes(each);
    }
    return result;
  }
}