job.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;

/**
 * <p>
 * The interface to be implemented by classes which represent a 'job' to be
 * performed.
 * </p>
 * 
 * <p>
 * Instances of <code>Job</code> must have a <code>public</code>
 * no-argument constructor.
 * </p>
 * 
 * <p>
 * <code>JobDataMap</code> provides a mechanism for 'instance member data'
 * that may be required by some implementations of this interface.
 * </p>
 * 
 * @see JobDetail
 * @see StatefulJob
 * @see Trigger
 * @see Scheduler
 * 
 * @author James House
 */
public interface Job {

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

    /**
     * <p>
     * Called by the <code>{@link Scheduler}</code> when a <code>{@link Trigger}</code>
     * fires that is associated with the <code>Job</code>.
     * </p>
     * 
     * <p>
     * The implementation may wish to set a 
     * {@link JobExecutionContext#setResult(Object) result} object on the 
     * {@link JobExecutionContext} before this method exits.  The result itself
     * is meaningless to Quartz, but may be informative to 
     * <code>{@link JobListener}s</code> or 
     * <code>{@link TriggerListener}s</code> that are watching the job's 
     * execution.
     * </p>
     * 
     * @return void (nothing) if job is successful.
     * @throws JobExecutionException
     *           if there is an exception while executing the job.
     */
    public void execute(JobExecutionContext context)
            throws JobExecutionException;

}