testclausesetevents2.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.reference;


import org.mandarax.kernel.ClauseSetChangeEvent;
import org.mandarax.kernel.Fact;
import org.mandarax.kernel.Rule;

/**
 * Test whether an event of the type <code>KEY_CHANGED</code> is fired (and handled)
 * if we change the predicate in the head of a rule.
 * @author <A href="http://www-ist.massey.ac.nz/JBDietrich" target="_top">Jens Dietrich</A>
 * @version 3.4 <7 March 05>
 * @since 1.1
 */
public class TestClauseSetEvents2 extends TestClauseSetEvents {

    /**
     * Constructor.
     */
    public TestClauseSetEvents2() {
        super ();
    }

    /**
     * Run the test.
     */
    public void testEvent() {
        EventHandler handler = new EventHandler ();
        Rule         rule    = Person.getRule ("isGrandFatherOf", "x", "z",
                                               "isFatherOf", "y", "z",
                                               "isFatherOf", "x", "y");
        Fact fact = Person.getFact ("isFatherOf", "Klaus", "Jens");

        rule.addClauseSetChangeListener (handler);
        rule.getHead ().setPredicate (fact.getPredicate ());

        // now check whether the event has been fired
        ClauseSetChangeEvent lastEvent =
            (ClauseSetChangeEvent) handler.handledEvents.peek ();

        assertTrue ((handler.handledEvents.size () == 1)
                && (lastEvent.getSource () == rule)
                && (lastEvent.getType () == ClauseSetChangeEvent.KEY_CHANGED));
    }
}