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.Father; 027 import biz.hammurapi.rules.tutorial.conclusions.Mother; 028 import biz.hammurapi.rules.tutorial.conclusions.Parent; 029 030 public class ParentRules extends Rule { 031 032 public ParentRules() { 033 setMethodFactTypes(Parent.class, new Class[] { Father.class, Mother.class }); 034 } 035 036 /** 037 * Male parent is father, female parent is mother. 038 * @param parent 039 * @return Brother or Sister. 040 */ 041 public Parent infer(Parent parent) { 042 043 if (parent.getSubject().isMale()) { 044 if (!(parent instanceof Father)) { 045 return new Father(parent.getSubject(), parent.getObject()); 046 } 047 } else { 048 if (!(parent instanceof Mother)) { 049 return new Mother(parent.getSubject(), parent.getObject()); 050 } 051 } 052 return null; 053 } 054 }