simpletimebroker.java

定时器开源项目, 相对于 jcrontab, Quartz 算是更完整的一个项目, 随著开发的版本上来, 他已经脱离只是写在程序里面的计时器, 在指定的时间或区间, 处理所指定的事件. 也加入了 se

/*
 * Copyright James House (c) 2001-2004
 * 
 * All rights reserved.
 * 
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are met: 1.
 * Redistributions of source code must retain the above copyright notice, this
 * list of conditions and the following disclaimer. 2. Redistributions in
 * binary form must reproduce the above copyright notice, this list of
 * conditions and the following disclaimer in the documentation and/or other
 * materials provided with the distribution.
 * 
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND ANY
 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE FOR ANY
 * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
 * ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 *  
 */
package org.quartz.simpl;

import java.util.Date;

import org.quartz.SchedulerConfigException;
import org.quartz.spi.TimeBroker;

/**
 * <p>
 * The interface to be implemented by classes that want to provide a mechanism
 * by which the <code>{@link org.quartz.core.QuartzScheduler}</code> can
 * reliably determine the current time.
 * </p>
 * 
 * <p>
 * In general, the default implementation of this interface (<code>{@link org.quartz.simpl.SimpleTimeBroker}</code>-
 * which simply uses <code>System.getCurrentTimeMillis()</code> )is
 * sufficient. However situations may exist where this default scheme is
 * lacking in its robustsness - especially when Quartz is used in a clustered
 * configuration. For example, if one or more of the machines in the cluster
 * has a system time that varies by more than a few seconds from the clocks on
 * the other systems in the cluster, scheduling confusion will result.
 * </p>
 * 
 * @see org.quartz.core.QuartzScheduler
 * 
 * @author James House
 */
public class SimpleTimeBroker implements TimeBroker {

    /*
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     * 
     * Interface.
     * 
     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
     */

    /**
     * <p>
     * Get the current time, simply using <code>new Date()</code>.
     * </p>
     */
    public Date getCurrentTime() {
        return new Date();
    }

    public void initialize() throws SchedulerConfigException {
        // do nothing...
    }

    public void shutdown() {
        // do nothing...
    }

}