001 /* 002 * hammurapi-rules-tutorial @mesopotamia.version@ 003 * Hammurapi rules tutorial. 004 * Copyright (C) 2006 Hammurapi Group 005 * 006 * This program is free software; you can redistribute it and/or 007 * modify it under the terms of the GNU Lesser General Public 008 * License as published by the Free Software Foundation; either 009 * version 2 of the License, or (at your option) any later version. 010 * 011 * This program is distributed in the hope that it will be useful, 012 * but WITHOUT ANY WARRANTY; without even the implied warranty of 013 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 014 * Lesser General Public License for more details. 015 * 016 * You should have received a copy of the GNU Lesser General Public 017 * License along with this library; if not, write to the Free Software 018 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA 019 * 020 * URL: http://http://www.hammurapi.biz 021 * e-Mail: support@hammurapi.biz 022 */ 023 package biz.hammurapi.rules.tutorial.rules; 024 025 import biz.hammurapi.rules.Rule; 026 import biz.hammurapi.rules.tutorial.conclusions.Brother; 027 import biz.hammurapi.rules.tutorial.conclusions.Child; 028 import biz.hammurapi.rules.tutorial.conclusions.Sibling; 029 import biz.hammurapi.rules.tutorial.conclusions.Sister; 030 031 public class SiblingRules extends Rule { 032 033 public SiblingRules() { 034 setMethodFactTypes(Sibling.class , new Class[] {Brother.class, Sister.class}); 035 setMethodFactTypes(new Class[] {Child.class, Child.class}, Sibling.class); 036 } 037 038 /** 039 * Male sibling is brother, female sibling is sister. 040 * If A is a sibling of B then B is a sibling of A. 041 * @param sibling 042 * @return Brother or Sister. 043 */ 044 public Sibling infer(Sibling sibling) { 045 post(new Sibling(sibling.getObject(), sibling.getSubject())); 046 047 if (sibling.getSubject().isMale()) { 048 if (!(sibling instanceof Brother)) { 049 return new Brother(sibling.getSubject(), sibling.getObject()); 050 } 051 } else { 052 if (!(sibling instanceof Sister)) { 053 return new Sister(sibling.getSubject(), sibling.getObject()); 054 } 055 } 056 return null; 057 } 058 059 /** 060 * If two children have common parent then they are siblings. 061 * @param child 062 * @param anotherChild 063 */ 064 public void infer(Child child, Child anotherChild) { 065 if (!child.getSubject().equals(anotherChild.getSubject()) 066 && child.getObject().equals(anotherChild.getObject())) { 067 post(new Sibling(child.getSubject(), anotherChild.getSubject())); 068 post(new Sibling(anotherChild.getSubject(), child.getSubject())); 069 } 070 } 071 }