holidayfactory.java

jcrontab是一个定时器开源项目包 目前提供存取文件或数据库, 把执行结果寄发 email, 简单地设置在 Tomcat, Resin, Jetty 及 JBoss 之上, 更是可以取代 cron

/**
 *  This file is part of the jcrontab package
 *  Copyright (C) 2001-2003 Israel Olalla
 *
 *  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
 *
 *  For questions, suggestions:
 *
 *  [e-mail]
 *
 */

package org.jcrontab.data;

import java.util.Properties;
import org.jcrontab.Crontab;
import org.jcrontab.log.Log;

/**
 * This Factory builds a HoliDay Source using teh given information.
 * @author $Author: iolalla $
 * @version $Revision: 1.3 $
 */

public class HoliDayFactory {
	
    private static HoliDaySource hds = null;
	
	/**
	 *	Default Constructor private
	 */
    private HoliDayFactory() {}
    /** 
	 * This method returns the DataFactory of the System This method
	 * grants the Singleton pattern
	 * @return DataSource I have a lot of doubts about how this method 
	 * is done.
 	 */
    public static HoliDaySource getInstance() throws Exception {
	   if ( hds == null) {
		 hds = ((HoliDaySource)Class.forName(Crontab.getInstance()
                                    .getProperty("org.jcrontab.data.holidaysource"))
                                    .newInstance());
	   }
       return hds;
    }
	
	/** 
	 * This method returns the HoliDaySource of the System
	 * @return HoliDaySource I have a lot of doubts about how this method 
	 * is done.
 	 */

    public HoliDaySource getDAO() {
        return hds;
    }
}