001package org.cpsolver.ifs.solver; 002 003import org.cpsolver.ifs.assignment.Assignment; 004import org.cpsolver.ifs.model.Neighbour; 005import org.cpsolver.ifs.model.Value; 006import org.cpsolver.ifs.model.Variable; 007 008/** 009 * IFS Solver Listener. 010 * 011 * @see Solver 012 * 013 * @author Tomáš Müller 014 * @version IFS 1.3 (Iterative Forward Search)<br> 015 * Copyright (C) 2006 - 2014 Tomáš Müller<br> 016 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br> 017 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br> 018 * <br> 019 * This library is free software; you can redistribute it and/or modify 020 * it under the terms of the GNU Lesser General Public License as 021 * published by the Free Software Foundation; either version 3 of the 022 * License, or (at your option) any later version. <br> 023 * <br> 024 * This library is distributed in the hope that it will be useful, but 025 * WITHOUT ANY WARRANTY; without even the implied warranty of 026 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 027 * Lesser General Public License for more details. <br> 028 * <br> 029 * You should have received a copy of the GNU Lesser General Public 030 * License along with this library; if not see <a href='http://www.gnu.org/licenses'>http://www.gnu.org/licenses</a>. 031 * 032 * @param <V> Variable 033 * @param <T> Value 034 **/ 035public interface SolverListener<V extends Variable<V, T>, T extends Value<V, T>> { 036 037 /** 038 * A variable was selected 039 * 040 * @param assignment current assignment 041 * @param iteration 042 * current iteration 043 * @param variable 044 * selected variable 045 * @return if false is returned the variable will be discarded (search continues with the next variable selection) 046 */ 047 public boolean variableSelected(Assignment<V, T> assignment, long iteration, V variable); 048 049 /** 050 * A value was selected 051 * 052 * @param assignment current assignment 053 * @param iteration 054 * current iteration 055 * @param variable 056 * selected variable 057 * @param value 058 * selected variable 059 * @return if false is returned the selected value is not assigned 060 */ 061 public boolean valueSelected(Assignment<V, T> assignment, long iteration, V variable, T value); 062 063 /** 064 * A neighbour was selected 065 * 066 * @param assignment current assignment 067 * @param iteration 068 * current iteration 069 * @param neighbour 070 * neighbour 071 * @return if false is returned the selected neighbour is not assigned 072 */ 073 public boolean neighbourSelected(Assignment<V, T> assignment, long iteration, Neighbour<V, T> neighbour); 074 075 /** 076 * Called when {@link ParallelSolver} failed to assign the given neighbour 077 * 078 * @param assignment current assignment 079 * @param iteration 080 * current iteration 081 * @param neighbour 082 * neighbour 083 */ 084 public void neighbourFailed(Assignment<V, T> assignment, long iteration, Neighbour<V, T> neighbour); 085 086}