Source code

001/** 
002 * Copyright (c) 2007-2008, Regents of the University of Colorado 
003 * All rights reserved.
004 * 
005 * Redistribution and use in source and binary forms, with or without
006 * modification, are permitted provided that the following conditions are met:
007 * 
008 * Redistributions of source code must retain the above copyright notice, this list of conditions and the following disclaimer. 
009 * Redistributions in binary form must reproduce the above copyright notice, this list of conditions and the following disclaimer in the documentation and/or other materials provided with the distribution. 
010 * Neither the name of the University of Colorado at Boulder nor the names of its contributors may be used to endorse or promote products derived from this software without specific prior written permission. 
011 * 
012 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
013 * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
014 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
015 * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
016 * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
017 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
018 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
019 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
020 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
021 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
022 * POSSIBILITY OF SUCH DAMAGE. 
023 */
024package org.cleartk.ml.feature.extractor;
025
026import java.util.Collections;
027import java.util.List;
028
029import org.apache.uima.jcas.JCas;
030import org.apache.uima.jcas.tcas.Annotation;
031import org.cleartk.ml.Feature;
032
033/**
034 * <br>
035 * Copyright (c) 2007-2008, Regents of the University of Colorado <br>
036 * All rights reserved.
037 * 
038 * 
039 * @author Philipp Wetzler
040 * 
041 */
042
043public class RelativePositionExtractor<T extends Annotation, U extends Annotation> implements
044    FeatureExtractor2<T, U> {
045
046  public static final String EQUALS = "EQUALS";
047
048  public static final String CONTAINS = "CONTAINS";
049
050  public static final String CONTAINEDBY = "CONTAINEDBY";
051
052  public static final String OVERLAPS_LEFT = "OVERLAPS_LEFT";
053
054  public static final String OVERLAPS_RIGHT = "OVERLAPS_RIGHT";
055
056  public static final String LEFTOF = "LEFTOF";
057
058  public static final String RIGHTOF = "RIGHTOF";
059
060  public List<Feature> extract(JCas view, T annotation1, U annotation2) {
061    String result;
062    if (equals(annotation1, annotation2)) {
063      result = EQUALS;
064    } else if (contains(annotation1, annotation2)) {
065      result = CONTAINS;
066    } else if (contains(annotation2, annotation1)) {
067      result = CONTAINEDBY;
068    } else if (overlaps(annotation1, annotation2) && beginsFirst(annotation1, annotation2)) {
069      result = OVERLAPS_LEFT;
070    } else if (overlaps(annotation1, annotation2)) {
071      result = OVERLAPS_RIGHT;
072    } else if (beginsFirst(annotation1, annotation2)) {
073      result = LEFTOF;
074    } else {
075      result = RIGHTOF;
076    }
077
078    return Collections.singletonList(new Feature("RelativePosition", result));
079  }
080
081  private boolean equals(Annotation a1, Annotation a2) {
082    return a1.getBegin() == a2.getBegin() && a1.getEnd() == a2.getEnd();
083  }
084
085  private boolean contains(Annotation a1, Annotation a2) {
086    return a1.getBegin() <= a2.getBegin() && a1.getEnd() >= a2.getEnd();
087  }
088
089  private boolean overlaps(Annotation a1, Annotation a2) {
090    return !(a1.getBegin() >= a2.getEnd() || a1.getEnd() <= a2.getBegin());
091  }
092
093  private boolean beginsFirst(Annotation a1, Annotation a2) {
094    return a1.getBegin() < a2.getBegin();
095  }
096}