content: /**
   * Licensed to the Apache Software Foundation (ASF) under one or more
   * contributor license agreements.  See the NOTICE file distributed with
   * this work for additional information regarding copyright ownership.
   * The ASF licenses this file to You 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.
   */
  package org.apache.activemq.broker.scheduler;
  
  import java.io.File;
  
  import org.apache.activemq.Service;
  
  /**
   * A Job Scheduler Store interface use to manage delay processing of Messaging
   * related jobs.
   */
  public interface JobSchedulerStore extends Service {
  
      /**
       * Gets the location where the Job Scheduler will write the persistent data used
       * to preserve and recover scheduled Jobs.
       *
       * If the scheduler implementation does not utilize a file system based store this
       * method returns null.
       *
       * @return the directory where persistent store data is written.
       */
      File getDirectory();
  
      /**
       * Sets the directory where persistent store data will be written.  This method
       * must be called before the scheduler store is started to have any effect.
       *
       * @param directory
       *      The directory where the job scheduler store is to be located.
       */
      void setDirectory(File directory);
  
      /**
       * The size of the current store on disk if the store utilizes a disk based store
       * mechanism.
       *
       * @return the current store size on disk.
       */
      long size();
  
      /**
       * Returns the JobScheduler instance identified by the given name.
       *
       * @param name
       *        the name of the JobScheduler instance to lookup.
       *
       * @return the named JobScheduler or null if none exists with the given name.
       *
       * @throws Exception if an error occurs while loading the named scheduler.
       */
      JobScheduler getJobScheduler(String name) throws Exception;
  
      /**
       * Removes the named JobScheduler if it exists, purging all scheduled messages
       * assigned to it.
       *
       * @param name
       *        the name of the scheduler instance to remove.
       *
       * @return true if there was a scheduler with the given name to remove.
       *
       * @throws Exception if an error occurs while removing the scheduler.
       */
      boolean removeJobScheduler(String name) throws Exception;
  }
  