001package net.sf.cpsolver.coursett.preference; 002 003import net.sf.cpsolver.coursett.Constants; 004 005/** 006 * Preference combination. <br> 007 * <br> 008 * A preference can be: 009 * <ul> 010 * <li>R .. required 011 * <li>P .. prohibited 012 * <li>number .. soft preference (smaller value is better) 013 * </ul> 014 * 015 * @version CourseTT 1.2 (University Course Timetabling)<br> 016 * Copyright (C) 2006 - 2010 Tomáš Müller<br> 017 * <a href="mailto:muller@unitime.org">muller@unitime.org</a><br> 018 * <a href="http://muller.unitime.org">http://muller.unitime.org</a><br> 019 * <br> 020 * This library is free software; you can redistribute it and/or modify 021 * it under the terms of the GNU Lesser General Public License as 022 * published by the Free Software Foundation; either version 3 of the 023 * License, or (at your option) any later version. <br> 024 * <br> 025 * This library is distributed in the hope that it will be useful, but 026 * WITHOUT ANY WARRANTY; without even the implied warranty of 027 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 028 * Lesser General Public License for more details. <br> 029 * <br> 030 * You should have received a copy of the GNU Lesser General Public 031 * License along with this library; if not see 032 * <a href='http://www.gnu.org/licenses/'>http://www.gnu.org/licenses/</a>. 033 */ 034public abstract class PreferenceCombination { 035 boolean iIsRequired = false; 036 boolean iIsProhibited = false; 037 038 /** Add preference a preference */ 039 public void addPreferenceProlog(String prologPref) { 040 addPreferenceInt(Constants.preference2preferenceLevel(prologPref)); 041 } 042 043 /** Returns combined preference from the given preferences */ 044 public void addPreferenceInt(int intPref) { 045 String prologPref = Constants.preferenceLevel2preference(intPref); 046 if (Constants.sPreferenceRequired.equals(prologPref)) 047 iIsRequired = true; 048 if (Constants.sPreferenceProhibited.equals(prologPref)) 049 iIsProhibited = true; 050 } 051 052 public boolean isRequired() { 053 return iIsRequired && !iIsProhibited; 054 } 055 056 public boolean isProhibited() { 057 return iIsProhibited; 058 } 059 060 public abstract int getPreferenceInt(); 061 062 public String getPreferenceProlog() { 063 if (iIsProhibited) 064 return Constants.sPreferenceProhibited; 065 if (iIsRequired) 066 return Constants.sPreferenceRequired; 067 return Constants.preferenceLevel2preference(getPreferenceInt()); 068 } 069 070 public static PreferenceCombination getDefault() { 071 return new SumPreferenceCombination(); 072 } 073}