    001    /*
    002     * Licensed to the Apache Software Foundation (ASF) under one or more
    003     * contributor license agreements.  See the NOTICE file distributed with
    004     * this work for additional information regarding copyright ownership.
    005     * The ASF licenses this file to You under the Apache License, Version 2.0
    006     * (the "License"); you may not use this file except in compliance with
    007     * the License.  You may obtain a copy of the License at
    008     *
    009     *     http://www.apache.org/licenses/LICENSE-2.0
    010     *
    011     * Unless required by applicable law or agreed to in writing, software
    012     * distributed under the License is distributed on an "AS IS" BASIS,
    013     * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
    014     * See the License for the specific language governing permissions and
    015     * limitations under the License.
    016     */
    017
    018    package org.apache.commons.configuration.reloading;
    019
    020    import org.apache.commons.configuration.FileConfiguration;
    021    import org.apache.commons.logging.Log;
    022    import org.apache.commons.logging.LogFactory;
    023
    024    /**
    025     * A strategy to reload configuration based on management requests. Designed for
    026     * JMX management.
    027     *
    028     * @author Nicolas De loof
    029     * @version $Id: ManagedReloadingStrategy.java 1210646 2011-12-05 21:25:01Z oheger $
    030     */
    031    public class ManagedReloadingStrategy implements ReloadingStrategy,
    032            ManagedReloadingStrategyMBean
    033    {
    034        /** The logger. */
    035        private Log log = LogFactory.getLog(ManagedReloadingStrategy.class);
    036
    037        /** Stores a reference to the associated configuration. */
    038        private FileConfiguration configuration;
    039
    040        /** A flag whether a reload is required. */
    041        private boolean reloadingRequired;
    042
    043        /**
    044         * @see org.apache.commons.configuration.reloading.ReloadingStrategy#init()
    045         */
    046        public void init()
    047        {
    048        }
    049
    050        /**
    051         * @see org.apache.commons.configuration.reloading.ReloadingStrategy#reloadingPerformed()
    052         */
    053        public void reloadingPerformed()
    054        {
    055            reloadingRequired = false;
    056        }
    057
    058        /**
    059         * Checks whether reloading is required. This implementation checks whether
    060         * the {@code refresh()} method has been invoked.
    061         *
    062         * @return a flag whether reloading is required
    063         * @see org.apache.commons.configuration.reloading.ReloadingStrategy#reloadingRequired()
    064         */
    065        public boolean reloadingRequired()
    066        {
    067            return reloadingRequired;
    068        }
    069
    070        /**
    071         * Sets the associated configuration.
    072         *
    073         * @param configuration the associated configuration
    074         */
    075        public void setConfiguration(FileConfiguration configuration)
    076        {
    077            this.configuration = configuration;
    078        }
    079
    080        /**
    081         * Tells this strategy that the monitored configuration file should be
    082         * refreshed. This method will typically be called from outside (through an
    083         * exposed MBean) on behalf of an administrator.
    084         *
    085         * @see org.apache.commons.configuration.reloading.ManagedReloadingStrategyMBean#refresh()
    086         */
    087        public void refresh()
    088        {
    089            log.info("Reloading configuration.");
    090            this.reloadingRequired = true;
    091            // force reloading
    092            configuration.isEmpty();
    093        }
    094    }