/*
* Syncany, www.syncany.org
* Copyright (C) 2011-2014 Philipp C. Heckel <philipp.heckel@gmail.com>
*
* This program is free software: you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation, either version 3 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
package org.syncany.operations.watch;
import static name.pachler.nio.file.StandardWatchEventKind.ENTRY_CREATE;
import static name.pachler.nio.file.StandardWatchEventKind.ENTRY_DELETE;
import static name.pachler.nio.file.StandardWatchEventKind.ENTRY_MODIFY;
import static name.pachler.nio.file.StandardWatchEventKind.OVERFLOW;
import static name.pachler.nio.file.ext.ExtendedWatchEventModifier.FILE_TREE;
import java.nio.file.Path;
import java.nio.file.Paths;
import java.util.List;
import name.pachler.nio.file.FileSystems;
import name.pachler.nio.file.WatchEvent;
import name.pachler.nio.file.WatchEvent.Kind;
import name.pachler.nio.file.WatchKey;
import name.pachler.nio.file.WatchService;
/**
* The Windows recursive file watcher monitors a folder (and its sub-folders)
* by registering a <em>recursive</em> watch on the root folder. This class is used
* only on Windows and uses jpathwatch-based {@link WatchService}.
*
* <p>Via the jpathwatch library, the class uses the Windows-native recursive folder-
* watching capabilities of Windows and thereby does not need to register watches on
* all sub-folders. Instead, only one watch on the root folder is needed.
*
* <p>When a file event occurs, a timer is started to wait for the file operations
* to settle. It is reset whenever a new event occurs. When the timer times out,
* an event is thrown through the {@link WatchListener}.
*
* @author Philipp C. Heckel <philipp.heckel@gmail.com>
*/
public class WindowsRecursiveWatcher extends RecursiveWatcher {
private WatchService watchService;
private WatchKey rootWatchKey;
public WindowsRecursiveWatcher(Path root, List<Path> ignorePaths, int settleDelay, WatchListener listener) {
super(root, ignorePaths, settleDelay, listener);
this.watchService = null;
this.rootWatchKey = null;
}
@Override
public void beforeStart() throws Exception {
name.pachler.nio.file.Path extLibRootDir = name.pachler.nio.file.Paths.get(root.toString());
watchService = FileSystems.getDefault().newWatchService();
rootWatchKey = extLibRootDir.register(watchService,
new Kind[] { ENTRY_CREATE, ENTRY_DELETE, ENTRY_MODIFY, OVERFLOW }, FILE_TREE);
}
@Override
protected void beforePollEventLoop() {
// Nothing must happen before the event loop.
}
@Override
public boolean pollEvents() throws Exception {
WatchKey watchKey = watchService.take();
List<WatchEvent<?>> watchEvents = watchKey.pollEvents();
boolean hasRelevantEvents = false;
// Filter ignored events
for (WatchEvent<?> watchEvent : watchEvents) {
if (watchEvent.kind() == ENTRY_CREATE || watchEvent.kind() == ENTRY_MODIFY || watchEvent.kind() == ENTRY_DELETE) {
boolean ignoreEvent = false;
name.pachler.nio.file.Path extLibFilePath = (name.pachler.nio.file.Path) watchEvent.context();
Path filePath = Paths.get(extLibFilePath.toString()).toAbsolutePath().normalize();
for (Path ignorePath : ignorePaths) {
if (filePath.startsWith(ignorePath.toAbsolutePath().normalize())) {
ignoreEvent = true;
break;
}
}
if (!ignoreEvent) {
hasRelevantEvents = true;
break;
}
}
}
watchKey.reset();
return hasRelevantEvents;
}
@Override
protected void watchEventsOccurred() {
// This watcher monitors recursively. No need to add more watches.
}
@Override
public synchronized void afterStop() throws Exception {
rootWatchKey.cancel();
watchService.close();
}
}