001 package net.sf.cpsolver.coursett.criteria.additional;
002
003 import java.util.Collection;
004 import java.util.Map;
005
006 import net.sf.cpsolver.coursett.criteria.StudentConflict;
007 import net.sf.cpsolver.coursett.model.Lecture;
008 import net.sf.cpsolver.coursett.model.Placement;
009 import net.sf.cpsolver.coursett.model.TimeLocation;
010 import net.sf.cpsolver.ifs.solver.Solver;
011 import net.sf.cpsolver.ifs.util.DataProperties;
012
013 /**
014 * Naive, yet effective approach for modeling student lunch breaks. This criterion
015 * is based on {@link StudentConflict} and it creates a conflict whenever there are
016 * two classes (that share students) overlapping with the lunch time which are one
017 * after the other with a break in between smaller than the requested lunch break.
018 * Lunch time is defined by StudentLunch.StartSlot and StudentLunch.EndStart
019 * properties (default is 11:00 am - 1:30 pm), with lunch break of at least
020 * StudentLunch.Length slots (default is 30 minutes). Such a conflict is weighted
021 * by Comparator.StudentLunchWeight, which defaults to Comparator.StudentConflictWeight.
022 *
023 * <br>
024 *
025 * @version CourseTT 1.2 (University Course Timetabling)<br>
026 * Copyright (C) 2006 - 2011 Tomas Muller<br>
027 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
028 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
029 * <br>
030 * This library is free software; you can redistribute it and/or modify
031 * it under the terms of the GNU Lesser General Public License as
032 * published by the Free Software Foundation; either version 3 of the
033 * License, or (at your option) any later version. <br>
034 * <br>
035 * This library is distributed in the hope that it will be useful, but
036 * WITHOUT ANY WARRANTY; without even the implied warranty of
037 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
038 * Lesser General Public License for more details. <br>
039 * <br>
040 * You should have received a copy of the GNU Lesser General Public
041 * License along with this library; if not see
042 * <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
043 */
044
045 public class StudentLuchBreak extends StudentConflict {
046 private int iLunchStart, iLunchEnd, iLunchLength;
047
048 @Override
049 public boolean init(Solver<Lecture, Placement> solver) {
050 iLunchStart = solver.getProperties().getPropertyInt("StudentLunch.StartSlot", (11 * 60) / 5);
051 iLunchEnd = solver.getProperties().getPropertyInt("StudentLunch.EndStart", (13 * 60 + 30) / 5);
052 iLunchLength = solver.getProperties().getPropertyInt("StudentLunch.Length", 30 / 5);
053 return super.init(solver);
054 }
055
056
057 @Override
058 public boolean isApplicable(Lecture l1, Lecture l2) {
059 return applicable(l1, l2);
060 }
061
062 @Override
063 public double getWeightDefault(DataProperties config) {
064 return config.getPropertyDouble("Comparator.StudentLunchWeight", config.getPropertyDouble("Comparator.StudentConflictWeight", 1.0));
065 }
066
067 @Override
068 public String getPlacementSelectionWeightName() {
069 return "Placement.StudentLunchWeight";
070 }
071
072 public boolean nolunch(Placement p1, Placement p2) {
073 if (p1 == null || p2 == null || overlaps(p1, p2)) return false;
074 if (p1.variable().isCommitted() && p2.variable().isCommitted()) return false;
075 TimeLocation t1 = p1.getTimeLocation(), t2 = p2.getTimeLocation();
076 if (!t1.shareDays(t2) || !t1.shareWeeks(t2)) return false;
077 int s1 = t1.getStartSlot(), s2 = t2.getStartSlot();
078 int e1 = t1.getStartSlot() + t1.getNrSlotsPerMeeting(), e2 = t2.getStartSlot() + t2.getNrSlotsPerMeeting();
079 if (e1 + iLunchLength > s2 && e2 + iLunchLength > s1 && e1 > iLunchStart && iLunchEnd > s1 && e2 > iLunchStart && iLunchEnd > s2)
080 return true;
081 return false;
082 }
083
084 @Override
085 public boolean inConflict(Placement p1, Placement p2) {
086 return nolunch(p1, p2);
087 }
088
089 @Override
090 public void getInfo(Map<String, String> info) {
091 super.getInfo(info);
092 double conf = getValue();
093 if (conf > 0.0)
094 info.put("Student lunch conflicts", String.valueOf(Math.round(conf)));
095 }
096
097 @Override
098 public void getInfo(Map<String, String> info, Collection<Lecture> variables) {
099 super.getInfo(info, variables);
100 double conf = getValue(variables);
101 if (conf > 0.0)
102 info.put("Student lunch conflicts", String.valueOf(Math.round(conf)));
103 }
104
105 }