001package org.cpsolver.ifs.model; 002 003import org.cpsolver.ifs.assignment.Assignment; 004 005/** 006 * Interface of a constraint that weakens with the time. 007 * 008 * @version CourseTT 1.3 (University Course Timetabling)<br> 009 * Copyright (C) 2006 - 2014 Tomáš Müller<br> 010 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br> 011 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br> 012 * <br> 013 * This library is free software; you can redistribute it and/or modify 014 * it under the terms of the GNU Lesser General Public License as 015 * published by the Free Software Foundation; either version 3 of the 016 * License, or (at your option) any later version. <br> 017 * <br> 018 * This library is distributed in the hope that it will be useful, but 019 * WITHOUT ANY WARRANTY; without even the implied warranty of 020 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 021 * Lesser General Public License for more details. <br> 022 * <br> 023 * You should have received a copy of the GNU Lesser General Public 024 * License along with this library; if not see 025 * <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>. 026 * 027 * @param <V> Variable 028 * @param <T> Value 029 */ 030public interface WeakeningConstraint<V extends Variable<V, T>, T extends Value<V, T>> { 031 /** 032 * Weaken the constraint. This method is called if the constraint 033 * participates in an unassigned of a variable. 034 * @param assignment current assignment 035 */ 036 public void weaken(Assignment<V, T> assignment); 037 038 039 /** 040 * Weaken the constraint enough so that it can assign the given 041 * value. 042 * @param assignment current assignment 043 * @param value a conflicting value to be assigned 044 */ 045 public void weaken(Assignment<V, T> assignment, T value); 046}