001    package net.sf.cpsolver.coursett.criteria;
002    
003    import net.sf.cpsolver.coursett.constraint.JenrlConstraint;
004    import net.sf.cpsolver.coursett.model.Lecture;
005    import net.sf.cpsolver.coursett.model.Placement;
006    import net.sf.cpsolver.coursett.model.TimeLocation;
007    import net.sf.cpsolver.ifs.util.DataProperties;
008    import net.sf.cpsolver.ifs.util.DistanceMetric;
009    
010    /**
011     * Student distance conflicts. This criterion counts student distance conflicts between classes.
012     * A distance conflict occurs when two classes that are attended by the same student (or students)
013     * are placed back-to-back in rooms that are too far a part. The combinations of classes
014     * that share students are maintained by {@link JenrlConstraint}. The critical distance is measured
015     * by {@link DistanceMetric#getDistanceInMinutes(double, double, double, double)} and compared
016     * witch class break time {@link TimeLocation#getBreakTime()}.
017     * <br>
018     * 
019     * @version CourseTT 1.2 (University Course Timetabling)<br>
020     *          Copyright (C) 2006 - 2011 Tomas Muller<br>
021     *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
022     *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
023     * <br>
024     *          This library is free software; you can redistribute it and/or modify
025     *          it under the terms of the GNU Lesser General Public License as
026     *          published by the Free Software Foundation; either version 3 of the
027     *          License, or (at your option) any later version. <br>
028     * <br>
029     *          This library is distributed in the hope that it will be useful, but
030     *          WITHOUT ANY WARRANTY; without even the implied warranty of
031     *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
032     *          Lesser General Public License for more details. <br>
033     * <br>
034     *          You should have received a copy of the GNU Lesser General Public
035     *          License along with this library; if not see
036     *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
037     */
038    public class StudentDistanceConflict extends StudentConflict {
039    
040        @Override
041        public boolean inConflict(Placement p1, Placement p2) {
042            return !ignore(p1, p2) && distance(getMetrics(), p1, p2);
043        }
044        
045        @Override
046        public boolean isApplicable(Lecture l1, Lecture l2) {
047            return !ignore(l1, l2) && applicable(l1, l2); // all student conflicts (including committed)
048        }
049        
050        @Override
051        public double getWeightDefault(DataProperties config) {
052            return config.getPropertyDouble("Comparator.DistStudentConflictWeight", 0.2);
053        }
054        
055        @Override
056        public String getPlacementSelectionWeightName() {
057            return "Placement.NrDistStudConfsWeight";
058        }
059    
060        
061    }