cachedclauseiterator.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.sql;

import java.util.Collection;
import java.util.Iterator;

import org.mandarax.kernel.Clause;

/**
 * A cached clause set iterator that simple takes a collection of (cached) facts
 * and iterates it.
 * @author <A href="http://www-ist.massey.ac.nz/JBDietrich" target="_top">Jens Dietrich</A>
 * @version 3.4 <7 March 05>
 * @since 1.5
 */
class CachedClauseIterator extends org.mandarax.util.AbstractClauseIterator {

    private Iterator iterateCache = null;

    /**
     * Constructor.
     * @param cache java.util.Collection
     */
    public CachedClauseIterator(Collection cache) {
        super ();

        iterateCache = cache.iterator ();
    }

    /**
     * Indicates whether there are more clauses.
     * @return true if there are more clauses, false otherwise
     */
    public boolean hasMoreClauses() {
        return iterateCache.hasNext ();
    }

    /**
     * Get the next clause.
     * @return the next clause
     */
    public Clause nextClause() {
        return(Clause) iterateCache.next ();
    }
}