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 *     https://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
018package org.apache.commons.configuration2.reloading;
019
020import org.apache.commons.logging.Log;
021import org.apache.commons.logging.LogFactory;
022
023/**
024 * A strategy to reload configuration based on management requests. Designed for JMX management.
025 */
026public class ManagedReloadingDetector implements ReloadingDetector, ManagedReloadingDetectorMBean {
027    /** The logger. */
028    private final Log log = LogFactory.getLog(ManagedReloadingDetector.class);
029
030    /** A flag whether a reload is required. */
031    private volatile boolean reloadingRequired;
032
033    /**
034     * Constructs a new instance.
035     */
036    public ManagedReloadingDetector() {
037        // empty
038    }
039
040    /**
041     * Checks whether reloading is required. This implementation checks whether the {@code refresh()} method has been
042     * invoked.
043     *
044     * @return a flag whether reloading is required
045     */
046    @Override
047    public boolean isReloadingRequired() {
048        return reloadingRequired;
049    }
050
051    /**
052     * Tells this strategy that the monitored configuration file should be refreshed. This method will typically be called
053     * from outside (through an exposed MBean) on behalf of an administrator.
054     *
055     * @see org.apache.commons.configuration2.reloading.ManagedReloadingDetectorMBean#refresh()
056     */
057    @Override
058    public void refresh() {
059        log.info("Reloading configuration.");
060        reloadingRequired = true;
061    }
062
063    /**
064     * {@inheritDoc} This implementation resets the internal flag indicating that a reload should be performed.
065     */
066    @Override
067    public void reloadingPerformed() {
068        reloadingRequired = false;
069    }
070}