mathtestcase.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 test.org.mandarax.lib.math;


import java.util.Iterator;

import org.mandarax.kernel.Clause;
import org.mandarax.kernel.ComplexTerm;
import org.mandarax.kernel.Fact;
import org.mandarax.kernel.Function;
import org.mandarax.kernel.Goal;
import org.mandarax.kernel.LogicFactory;
import org.mandarax.kernel.Predicate;
import org.mandarax.kernel.Term;
import org.mandarax.util.AutoFacts;

/**
 * Superclass for testing predicates and functions from the math package.
 * All tests work as follows: we build an auto fact set, fetch an iterator and
 * count the facts generated. The number of facts is compared with the expected number of facts.
 * Facts are printed out on System.out.
 * @author <A href="http://www-ist.massey.ac.nz/JBDietrich" target="_top">Jens Dietrich</A>
 * @version 3.4 <7 March 05>
 * @since 1.6
 */
public abstract class MathTestCase extends junit.framework.TestCase {

    protected LogicFactory lfactory = LogicFactory.getDefaultFactory ();

    /**
     * Constructor.
     */
    public MathTestCase() {
        super ("test");
    }

    /**
     * Convenient method to build a complex term from a function f and one term.
     * The method <code>toTerm</code> is used to interprete objects as terms.
     * @return a complex term
     * @param f a function
     * @param obj an object defining a term
     */
    protected ComplexTerm buildComplexTerm(Function f, Object obj) {
        Term[] terms = { toTerm (obj) };

        return lfactory.createComplexTerm (f, terms);
    }

    /**
     * Convenient method to build a complex term from a function f and two terms.
     * The method <code>toTerm</code> is used to interprete objects as terms.
     * @return a complex term
     * @param f a function
     * @param obj1 an object defining a term
     * @param obj2 an object defining a term
     */
    protected ComplexTerm buildComplexTerm(Function f, Object obj1,
                                           Object obj2) {
        Term[] terms = { toTerm (obj1), toTerm (obj2) };

        return lfactory.createComplexTerm (f, terms);
    }

    /**
     * Convenient method to build a fact from a predicate p and one term.
     * The method <code>toTerm</code> is used to interprete objects as terms.
     * @return a fact
     * @param p a predicate
     * @param obj an object defining a term
     */
    protected Fact buildFact(Predicate p, Object obj) {
        Term[] terms = { toTerm (obj) };

        return lfactory.createFact (p, terms);
    }

    /**
     * Convenient method to build a fact from a predicate p and two terms.
     * The method <code>toTerm</code> is used to interprete objects as terms.
     * @return a fact
     * @param p a predicate
     * @param obj1 an object defining a term
     * @param obj2 an object defining a term
     */
    protected Fact buildFact(Predicate p, Object obj1, Object obj2) {
        Term[] terms = { toTerm (obj1), toTerm (obj2) };

        return lfactory.createFact (p, terms);
    }

    /**
     * Convenient method to build a fact from a predicate p and three terms.
     * The method <code>toTerm</code> is used to interprete objects as terms.
     * @return a fact

     * @param p a predicate
     * @param obj1 an object defining a term
     * @param obj2 an object defining a term
     * @param obj3 an object defining a term
     */
    protected Fact buildFact(Predicate p, Object obj1, Object obj2,
                             Object obj3) {
        Term[] terms = { toTerm (obj1), toTerm (obj2), toTerm (obj3) };

        return lfactory.createFact (p, terms);
    }

    /**
     * Get the auto facts.
     * @return an auto facts clause set
     */
    protected abstract AutoFacts getAutoFacts();

    /**
     * Get the expected number of generated facts.
     * @return the number of facts expected
     */
    protected abstract int getExpected();

    /**
     * Get the query fact.
     * @return a query fact.
     */
    protected abstract Fact getQueryFact();

    /**
     * Get the type (e.g. Integer.class or Double.class) we want to test.
     * @return the type to be tested
     */
    protected abstract Class getType();

    /**
     * Perform the test.
     */
    public void test() {
        AutoFacts af    = getAutoFacts ();
        Clause    query = new Goal (getQueryFact ());

        System.out.println ("PERFORMING TEST " + getClass ());

        int counter = 0;

        for(Iterator it = af.clauses (query, null); it.hasNext (); ) {
            counter = counter + 1;

            System.out.println ("Next generated fact is: " + it.next ());
        }

        System.out.println ();
        assertTrue (getExpected () == counter);
    }

    /**
     * Convinient method to build terms from objects.
     * If the object is a string, a variable with this name
     * is returned.
     * If it is already a term, we just return this term.
     * @return a term
     * @param obj the object to be converted to a term
     * @param index an index (will be appended to the variable name)
     */
    private Term toTerm(Object obj) {
        if(obj instanceof Term) {
            return(Term) obj;
        }

        if(obj instanceof String) {
            return lfactory.createVariableTerm (obj.toString (), getType ());
        }

        throw new IllegalArgumentException ("Cannot build term from object "
                                            + obj);
    }
}