001package net.sf.cpsolver.exam.criteria; 002 003import java.util.Set; 004 005import net.sf.cpsolver.exam.model.Exam; 006import net.sf.cpsolver.exam.model.ExamInstructor; 007import net.sf.cpsolver.exam.model.ExamPeriod; 008import net.sf.cpsolver.exam.model.ExamPlacement; 009import net.sf.cpsolver.ifs.util.DataProperties; 010 011/** 012 * Number of back-to-back instructor conflicts. I.e., number of cases when 013 * an exam is attended by an instructor that attends some other exam at 014 * the previous {@link ExamPeriod#prev()} or following 015 * {@link ExamPeriod#next()} period. If 016 * {@link StudentBackToBackConflicts#isDayBreakBackToBack()} is false, back-to-back conflicts 017 * are only considered between consecutive periods that are of the same day. 018 * <br><br> 019 * Back-to-back instructor conflict weight can be set by problem property 020 * Exams.InstructorBackToBackConflictWeight, or in the input xml file, 021 * property instructorBackToBackConflictWeight. 022 * 023 * 024 * <br> 025 * 026 * @version ExamTT 1.2 (Examination Timetabling)<br> 027 * Copyright (C) 2008 - 2012 Tomáš Müller<br> 028 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br> 029 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br> 030 * <br> 031 * This library is free software; you can redistribute it and/or modify 032 * it under the terms of the GNU Lesser General Public License as 033 * published by the Free Software Foundation; either version 3 of the 034 * License, or (at your option) any later version. <br> 035 * <br> 036 * This library is distributed in the hope that it will be useful, but 037 * WITHOUT ANY WARRANTY; without even the implied warranty of 038 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 039 * Lesser General Public License for more details. <br> 040 * <br> 041 * You should have received a copy of the GNU Lesser General Public 042 * License along with this library; if not see 043 * <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>. 044 */ 045public class InstructorBackToBackConflicts extends StudentBackToBackConflicts { 046 047 @Override 048 public String getWeightName() { 049 return "Exams.InstructorBackToBackConflictWeight"; 050 } 051 052 @Override 053 public String getXmlWeightName() { 054 return "instructorBackToBackConflictWeight"; 055 } 056 057 @Override 058 public double getWeightDefault(DataProperties config) { 059 return 10.0; 060 } 061 062 @Override 063 public double getValue(ExamPlacement value, Set<ExamPlacement> conflicts) { 064 Exam exam = value.variable(); 065 int penalty = 0; 066 for (ExamInstructor s : exam.getInstructors()) { 067 if (value.getPeriod().prev() != null) { 068 if (isDayBreakBackToBack() || value.getPeriod().prev().getDay() == value.getPeriod().getDay()) { 069 Set<Exam> exams = s.getExams(value.getPeriod().prev()); 070 int nrExams = exams.size() + (exams.contains(exam) ? -1 : 0); 071 penalty += nrExams; 072 } 073 } 074 if (value.getPeriod().next() != null) { 075 if (isDayBreakBackToBack() || value.getPeriod().next().getDay() == value.getPeriod().getDay()) { 076 Set<Exam> exams = s.getExams(value.getPeriod().next()); 077 int nrExams = exams.size() + (exams.contains(exam) ? -1 : 0); 078 penalty += nrExams; 079 } 080 } 081 } 082 return penalty; 083 } 084 085 @Override 086 public String getName() { 087 return "Instructor Back-To-Back Conflicts"; 088 } 089 090 @Override 091 public String toString() { 092 return "iBTB:" + sDoubleFormat.format(getValue()); 093 } 094 095}