/*  * Copyright 2004-2005 OpenSymphony  *  * Licensed under the Apache License, Version 2.0 (the "License"); you may not  * use this file except in compliance with the License. You may obtain a copy  * of the License at  *  *   http://www.apache.org/licenses/LICENSE-2.0  *    * Unless required by applicable law or agreed to in writing, software  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the  * License for the specific language governing permissions and limitations  * under the License. *  *//* * Previously Copyright (c) 2001-2004 James House */package org.quartz;/** * <p> * A marker interface for <code>{@link org.quartz.JobDetail}</code> s that * wish to have their state maintained between executions. * </p> *  * <p> * <code>StatefulJob</code> instances follow slightly different rules from * regular <code>Job</code> instances. The key difference is that their * associated <code>{@link JobDataMap}</code> is re-persisted after every * execution of the job, thus preserving state for the next execution. The * other difference is that stateful jobs are not allowed to execute * concurrently, which means new triggers that occur before the completion of * the <code>execute(xx)</code> method will be delayed. * </p> *  * @see Job * @see JobDetail * @see JobDataMap * @see Scheduler *  * @author James House */public interface StatefulJob extends Job {    /*     * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~     *      * Interface.     *      * ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~     */}