/*  PAT: Persistent Applications Toolkit (patsystem.sf.net)
 *  Copyright (C) 2004, 2005  Tomasz Nazar, nthx at irc dot pl
 *  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
 *  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
 *  Full version of the license is /docs/LICENSE.txt
package org.nthx.pat;

import org.prevayler.AlarmClock;
import org.prevayler.PrevalentSystem;

/** "Root object" (@@ pat.root) must still be an instance of 
 *  {@link PrevalentSystem}, so this is a mixin for it.
 *  <p>I copied it from original Prevayler package and I think it
 *  might also be possible to provide direct "link" to original Prevayler class
 *  in 'pat-aop.xml' config, but for safety I keep it here.
 *  @version $Id: PrevalentSystemMixin.java 3725 2005-06-09 23:57:03Z nthx $
 *  @author nthx@users.sourceforge.net
public class PrevalentSystemMixin
       implements PrevalentSystem
    private AlarmClock clock;

    public PrevalentSystemMixin()

    /** See org.prevayler.PrevalentSystem.clock() */
    public AlarmClock clock()
        return clock;

    /** See org.prevayler.PrevalentSystem.clock(AlarmClock) */
    public void clock(AlarmClock clock)
        if (this.clock != null) throw new IllegalStateException("The clock had already been set.");
        this.clock = clock;

    final static long serialVersionUID = 1L;