001    package net.sf.cpsolver.coursett.constraint;
002    
003    /** Interface of a constraint that weakens with the time.
004     * 
005     * @version
006     * CourseTT 1.1 (University Course Timetabling)<br>
007     * Copyright (C) 2006 Tomáš Müller<br>
008     * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
009     * Lazenska 391, 76314 Zlin, Czech Republic<br>
010     * <br>
011     * This library is free software; you can redistribute it and/or
012     * modify it under the terms of the GNU Lesser General Public
013     * License as published by the Free Software Foundation; either
014     * version 2.1 of the License, or (at your option) any later version.
015     * <br><br>
016     * This library is distributed in the hope that it will be useful,
017     * but WITHOUT ANY WARRANTY; without even the implied warranty of
018     * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
019     * Lesser General Public License for more details.
020     * <br><br>
021     * You should have received a copy of the GNU Lesser General Public
022     * License along with this library; if not, write to the Free Software
023     * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
024     */
025    
026    public interface WeakeningConstraint {
027        /** 
028         * Weaken the constraint. 
029         * This method is called if the constraint participates in an unassigned of a variable.
030         */ 
031            public void weaken();
032    }