    001package org.cpsolver.ifs.model;
    002
    003import org.cpsolver.ifs.assignment.Assignment;
    004
    005/**
    006 * IFS variable listener.
    007 *
    008 * @see Variable
    009 *
    010 * @author  Tomáš Müller
    011 * @version IFS 1.3 (Iterative Forward Search)<br>
    012 *          Copyright (C) 2006 - 2014 Tomáš Müller<br>
    013 *          <a href="mailto:muller@unitime.org">muller@unitime.org</a><br>
    014 *          <a href="http://muller.unitime.org">http://muller.unitime.org</a><br>
    015 * <br>
    016 *          This library is free software; you can redistribute it and/or modify
    017 *          it under the terms of the GNU Lesser General Public License as
    018 *          published by the Free Software Foundation; either version 3 of the
    019 *          License, or (at your option) any later version. <br>
    020 * <br>
    021 *          This library is distributed in the hope that it will be useful, but
    022 *          WITHOUT ANY WARRANTY; without even the implied warranty of
    023 *          MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
    024 *          Lesser General Public License for more details. <br>
    025 * <br>
    026 *          You should have received a copy of the GNU Lesser General Public
    027 *          License along with this library; if not see
    028 *          <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>.
    029 *
    030 * @param <T> Value
    031 */
    032public interface VariableListener<T extends Value<?, T>> {
    033    /**
    034     * Called by the variable when a value is assigned to it
    035     *
    036     * @param assignment current assignment
    037     * @param iteration
    038     *            current iteration
    039     * @param value
    040     *            assigned to the variable
    041     */
    042    public void variableAssigned(Assignment<?, T> assignment, long iteration, T value);
    043
    044    /**
    045     * Called by the variable when a value is unassigned from it
    046     *
    047     * @param assignment current assignment
    048     * @param iteration
    049     *            current iteration
    050     * @param value
    051     *            unassigned from the variable
    052     */
    053    public void variableUnassigned(Assignment<?, T> assignment, long iteration, T value);
    054
    055    /**
    056     * Called by the variable when a value is permanently removed from its
    057     * domain
    058     *
    059     * @param iteration
    060     *            current iteration
    061     * @param value
    062     *            removed from the variable's domain
    063     */
    064    public void valueRemoved(long iteration, T value);
    065}