package org.gudy.azureus2.core3.predicate;

/*
 * Created on 5-Mar-2004
 * Created by James Yeh
 * Copyright (C) 2004 Aelitis, All Rights Reserved.
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * This program 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 General Public License for more details.
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
 *
 * AELITIS, SARL au capital de 30,000 euros
 * 8 Allee Lenotre, La Grille Royale, 78600 Le Mesnil le Roi, France.
 *
 */

/**
 * MutableCompositePredicateDecorator decorates existing composite Predicates to support
 * add and removal operations.
 * @version 1.0
 * @author James Yeh
 */
public interface MutableCompositePredicateDecorator
{
    /**
     * <p>
     * Adds a predicate to the list of evaluations the composite predicate contains
     * </p>
     * <p>
     * If the predicate already exists in the list, it is not added.
     * </p>
     * @param aPredicate A predicate
     * @return False if the predicate already exists in the list
     */
    public boolean addPredicate(Predicable aPredicate);

    /**
     * Removes a predicate from the list of evaluations the composite predicate contains
     * @param aPredicate A predicate
     * @return The predicate that was removed; null if the predicate was not found
     */
    public Predicable removePredicate(Predicable aPredicate);
}
