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* 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
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package org.apache.ctakes.assertion.medfacts.cleartk.extractors;
import java.util.ArrayList;
import java.util.List;
import org.apache.ctakes.typesystem.type.syntax.BaseToken;
import org.apache.ctakes.typesystem.type.syntax.ConllDependencyNode;
import org.apache.ctakes.typesystem.type.textsem.IdentifiedAnnotation;
import org.apache.ctakes.typesystem.type.textsem.Predicate;
import org.apache.ctakes.typesystem.type.textsem.SemanticArgument;
import org.apache.ctakes.typesystem.type.textsem.SemanticRoleRelation;
import org.apache.ctakes.typesystem.type.textspan.Sentence;
import org.apache.uima.jcas.JCas;
import org.apache.uima.jcas.cas.FSList;
import org.apache.uima.jcas.cas.NonEmptyFSList;
import org.apache.uima.jcas.tcas.Annotation;
import org.cleartk.classifier.Feature;
import org.cleartk.classifier.feature.extractor.CleartkExtractorException;
import org.cleartk.classifier.feature.extractor.simple.SimpleFeatureExtractor;
import org.uimafit.util.JCasUtil;
public class SRLFeatureExtractor implements SimpleFeatureExtractor {
@Override
public List<Feature> extract(JCas jCas, Annotation entity)
throws CleartkExtractorException {
List<Feature> feats = new ArrayList<Feature>();
List<Sentence> sents = JCasUtil.selectCovering(jCas, Sentence.class, entity.getBegin(), entity.getEnd());
if(sents!= null && sents.size() > 0){
List<String> srlFeats = getEntityFeats(jCas, (IdentifiedAnnotation) entity, sents.get(0));
for(String feat : srlFeats){
feats.add(new Feature(feat));
}
}
return feats;
}
public static ArrayList<String> getEntityFeats(JCas jcas, IdentifiedAnnotation ent, Sentence sent){
ArrayList<String> feats = new ArrayList<String>();
List<BaseToken> words = JCasUtil.selectCovered(jcas, BaseToken.class, ent);
if(words != null && words.size() > 0){
BaseToken lastWord = words.get(words.size()-1);
List<SemanticArgument> args = JCasUtil.selectCovered(jcas, SemanticArgument.class, lastWord);
Predicate pred = null;
if(args.size() > 0){
SemanticArgument entArg = args.get(0);
SemanticRoleRelation entRel = entArg.getRelation();
pred = entRel.getPredicate();
String feat = "pred:" + pred.getCoveredText().replace(' ', '_').toLowerCase();
feats.add(feat);
// get the relation this arg belongs to, then its predicate, then the other arguments (via relations)
FSList rels = entArg.getRelation().getPredicate().getRelations();
while(rels instanceof NonEmptyFSList){
NonEmptyFSList node = (NonEmptyFSList) rels;
SemanticRoleRelation curRel = (SemanticRoleRelation) node.getHead();
SemanticArgument curArg = curRel.getArgument();
if(entArg.getCoveredText().equals(curArg.getCoveredText())){
// show which arg is the current arg
// out.print("*");
}else{
feat = "SRL: " + curArg.getLabel() + ":" + curArg.getCoveredText().replace(' ', '_').toLowerCase();
feats.add(feat);
}
rels = node.getTail();
}
}
// now look for dependency relations:
List<ConllDependencyNode> coveredNodes = JCasUtil.selectCovered(jcas, ConllDependencyNode.class, lastWord);
if(coveredNodes.size() > 0){
ConllDependencyNode curNode = coveredNodes.get(0);
ConllDependencyNode predNode = null;
if(pred != null){
List<ConllDependencyNode> predNodes = JCasUtil.selectCovered(jcas, ConllDependencyNode.class, pred);
if(predNodes.size() > 0){
predNode = predNodes.get(0);
}
}
List<ConllDependencyNode> allNodes = JCasUtil.selectCovered(jcas, ConllDependencyNode.class, sent);
for(ConllDependencyNode node : allNodes){
if(node.getHead() == curNode){
String feat = "entpointer:" + node.getDeprel() + ":" + node.getCoveredText().replace(' ', '_').toLowerCase();
feats.add(feat);
}else if(predNode != null && node.getHead() == predNode){
String feat = "predpointer:" + node.getDeprel() + ":" + node.getCoveredText().replace(' ', '_').toLowerCase();
feats.add(feat);
}
}
}
}
return feats;
}
}