| /* |
| * 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.commons.configuration2.reloading; |
| |
| import org.apache.commons.configuration2.ex.ConfigurationRuntimeException; |
| import org.apache.commons.configuration2.io.FileHandler; |
| import org.apache.commons.configuration2.io.FileSystem; |
| import org.apache.commons.logging.Log; |
| import org.apache.commons.logging.LogFactory; |
| import org.apache.commons.vfs2.FileObject; |
| import org.apache.commons.vfs2.FileSystemException; |
| import org.apache.commons.vfs2.FileSystemManager; |
| import org.apache.commons.vfs2.VFS; |
| |
| /** |
| * <p> |
| * A file-based reloading strategy that uses <a href="https://commons.apache.org/vfs/">Commons VFS</a> to determine when |
| * a file was changed. |
| * </p> |
| * <p> |
| * This reloading strategy is very similar to {@link FileHandlerReloadingDetector}, except for the fact that it uses VFS |
| * and thus can deal with a variety of different configuration sources. |
| * </p> |
| * <p> |
| * This strategy only works with FileConfiguration instances. |
| * </p> |
| * |
| * @since 1.7 |
| */ |
| public class VFSFileHandlerReloadingDetector extends FileHandlerReloadingDetector { |
| /** Stores the logger. */ |
| private final Log log = LogFactory.getLog(getClass()); |
| |
| /** |
| * Creates a new instance of {@code VFSFileHandlerReloadingDetector} and initializes it with an empty |
| * {@code FileHandler} object. |
| */ |
| public VFSFileHandlerReloadingDetector() { |
| } |
| |
| /** |
| * Creates a new instance of {@code VFSFileHandlerReloadingDetector} and initializes it with the given |
| * {@code FileHandler} object. |
| * |
| * @param handler the {@code FileHandler} |
| */ |
| public VFSFileHandlerReloadingDetector(final FileHandler handler) { |
| super(handler); |
| } |
| |
| /** |
| * Creates a new instance of {@code VFSFileHandlerReloadingDetector} and initializes it with the given |
| * {@code FileHandler} object and the given refresh delay. |
| * |
| * @param handler the {@code FileHandler} |
| * @param refreshDelay the refresh delay |
| */ |
| public VFSFileHandlerReloadingDetector(final FileHandler handler, final long refreshDelay) { |
| super(handler, refreshDelay); |
| } |
| |
| /** |
| * Gets the file that is monitored by this strategy. Note that the return value can be <b>null </b> under some |
| * circumstances. |
| * |
| * @return the monitored file |
| */ |
| protected FileObject getFileObject() { |
| if (!getFileHandler().isLocationDefined()) { |
| return null; |
| } |
| |
| try { |
| final FileSystemManager fsManager = VFS.getManager(); |
| final String uri = resolveFileURI(); |
| if (uri == null) { |
| throw new ConfigurationRuntimeException("Unable to determine file to monitor"); |
| } |
| return fsManager.resolveFile(uri); |
| } catch (final FileSystemException fse) { |
| final String msg = "Unable to monitor " + getFileHandler().getURL().toString(); |
| log.error(msg); |
| throw new ConfigurationRuntimeException(msg, fse); |
| } |
| } |
| |
| /** |
| * {@inheritDoc} This implementation uses Commons VFS to obtain a {@code FileObject} and read the date of the last |
| * modification. |
| */ |
| @Override |
| protected long getLastModificationDate() { |
| final FileObject file = getFileObject(); |
| try { |
| if (file == null || !file.exists()) { |
| return 0; |
| } |
| |
| return file.getContent().getLastModifiedTime(); |
| } catch (final FileSystemException ex) { |
| log.error("Unable to get last modified time for" + file.getName().getURI(), ex); |
| return 0; |
| } |
| } |
| |
| /** |
| * Resolves the URI of the monitored file. |
| * |
| * @return the URI of the monitored file or <b>null</b> if it cannot be resolved |
| */ |
| protected String resolveFileURI() { |
| final FileSystem fs = getFileHandler().getFileSystem(); |
| return fs.getPath(null, getFileHandler().getURL(), getFileHandler().getBasePath(), getFileHandler().getFileName()); |
| } |
| } |