001package net.sf.cpsolver.coursett.criteria.placement; 002 003import java.util.Collection; 004import java.util.Map; 005import java.util.Set; 006 007import net.sf.cpsolver.coursett.model.Lecture; 008import net.sf.cpsolver.coursett.model.Placement; 009import net.sf.cpsolver.ifs.extension.ConflictStatistics; 010import net.sf.cpsolver.ifs.extension.Extension; 011import net.sf.cpsolver.ifs.solution.Solution; 012import net.sf.cpsolver.ifs.solution.SolutionListener; 013import net.sf.cpsolver.ifs.solver.Solver; 014 015/** 016 * Hard conflicts weighted by the conflict-based statistics (past occurrences). 017 * <br> 018 * 019 * @version CourseTT 1.2 (University Course Timetabling)<br> 020 * Copyright (C) 2006 - 2011 Tomáš Müller<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 */ 038public class WeightedHardConflicts extends PlacementSelectionCriterion implements SolutionListener<Lecture, Placement> { 039 protected ConflictStatistics<Lecture, Placement> iStat = null; 040 protected long iIteration = 0; 041 042 @Override 043 public boolean init(Solver<Lecture, Placement> solver) { 044 super.init(solver); 045 for (Extension<Lecture, Placement> extension : solver.getExtensions()) { 046 if (ConflictStatistics.class.isInstance(extension)) 047 iStat = (ConflictStatistics<Lecture, Placement>) extension; 048 } 049 solver.currentSolution().addSolutionListener(this); 050 return true; 051 } 052 053 @Override 054 public String getPlacementSelectionWeightName() { 055 return "Placement.NrConflictsWeight"; 056 } 057 058 @Override 059 public double getValue(Placement value, Set<Placement> conflicts) { 060 return (iStat == null || conflicts == null ? 0.0 : iStat.countRemovals(iIteration, conflicts, value)); 061 } 062 063 @Override 064 public double getPlacementSelectionWeightDefault(int level) { 065 return (level == 0 ? 3.0 : 0.0); 066 } 067 068 @Override 069 public void solutionUpdated(Solution<Lecture, Placement> solution) { 070 iIteration = solution.getIteration(); 071 } 072 073 @Override 074 public void getInfo(Solution<Lecture, Placement> solution, Map<String, String> info) { 075 } 076 077 @Override 078 public void getInfo(Solution<Lecture, Placement> solution, Map<String, String> info, Collection<Lecture> variables) { 079 } 080 081 @Override 082 public void bestCleared(Solution<Lecture, Placement> solution) { 083 iIteration = solution.getIteration(); 084 } 085 086 @Override 087 public void bestSaved(Solution<Lecture, Placement> solution) { 088 iIteration = solution.getIteration(); 089 } 090 091 @Override 092 public void bestRestored(Solution<Lecture, Placement> solution) { 093 iIteration = solution.getIteration(); 094 } 095 096}