predicatesandfunctions.java

Mandarax是一个规则引擎的纯Java实现。它支持多类型的事实和基于反映的规则

/*
 * Copyright (C) 1999-2004 <A href="http://www-ist.massey.ac.nz/JBDietrich" target="_top">Jens Dietrich</a>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

package org.mandarax.examples.crm;

import org.mandarax.examples.crm.domainmodel.*;
import org.mandarax.kernel.*;
import org.mandarax.kernel.meta.JFunction;
import org.mandarax.util.*;

/**
 * Factory for predicates and functions used in this example.
 * @author <A href="http://www-ist.massey.ac.nz/JBDietrich" target="_top">Jens Dietrich</A>
 * @version 3.4 <7 March 05>
 * @since 3.4
 */
public class PredicatesAndFunctions   { 
	private static LogicFactorySupport lfs = new LogicFactorySupport();
	/**
	 * Constructor.
	 */
	public PredicatesAndFunctions() {
		super();
	}

	/**
	 * Get the "get turnover" function
	 * @return a function
	 */
	public static Function getFunctionTurnover() {
	    try {
	        Class[] par = { Integer.TYPE };
	
	        return new JFunction (
	            Customer.class.getMethod ("getTurnover", par), "turnover");
	    } catch(NoSuchMethodException x) {
	        x.printStackTrace (System.err);
	    }
	
	    return null;
	}

	/**
	 * Get the "get turnover made with a certain kind of payment" function
	 * @return a function
	 */
	public static Function getFunctionTurnoverForKindOfPayment() {
	    try {
	        Class[] par = { Integer.TYPE, KindOfPayment.class };
	
	        return new JFunction (
	            Customer.class.getMethod ("getTurnover", par),
	            "turnover/payment");
	    } catch(NoSuchMethodException x) {
	        x.printStackTrace (System.err);
	    }
	
	    return null;
	}

	/**
	 * Get the "customer gets a certain discount" predicate
	 * @return a predicate
	 */
	 public static Predicate getPredicateGetDiscount() {
	    Class[] par = { Customer.class, Discount.class };
	
	    return new SimplePredicate ("getsDiscount", par);
	}

	/**
	 * Get the "customer is in a certain category" predicate
	 * @return a predicate
	 */
	public static Predicate getPredicateHasCategory() {
	    Class[] par = { Customer.class, Category.class };
	
	    return new SimplePredicate ("hasCategory", par);
	
	    //Class[] par2 = {Customer.class,Discount.class};
	    //predicates[1] = new SimplePredicate("getsDiscount",par2);
	}

}