/**
* Distributes the given file change event among all file change listeners.
*
* @param event the file change event to distribute
*/
protected void distributeFileChangeEvent(FileChangeEvent event) {
Iterator it = fileListeners.iterator();
while (it.hasNext()) {
FileChangeListener listener = (FileChangeListener) it.next();
listener.fileChanged(event);
}
}
@Override
public void run() {
synchronized (lock) {
for (Map.Entry<File, Long> entry : files.entrySet()) {
File file = entry.getKey();
long lastModifiedTime = entry.getValue().longValue();
long newModifiedTime = file.exists() ? file.lastModified() : -1;
// check if file has been changed
if (newModifiedTime != lastModifiedTime) {
// store new modified time
entry.setValue(new Long(newModifiedTime));
// notify listeners
for (FileChangeListener listener : listeners) {
listener.onFileChange(file);
}
}
}
}
}
protected void fireFileChangeEvent(FileChangeListener listener, String fileName) {
listener.fileChanged(fileName);
}
/**
* Remove the listener from the notification list.
*
* @param listener the listener to be removed.
*/
public void removeFileChangeListener(FileChangeListener listener, String fileName) {
FileMonitorTask task = (FileMonitorTask) timerTasks.remove(fileName + listener.hashCode());
if (task != null) {
task.cancel();
}
}
/**
* Start monitoring a file.
*
* @param listener listener to notify when the file changed.
* @param fileName name of the file to monitor.
* @param period polling period in milliseconds.
*/
public void addFileChangeListener(FileChangeListener listener, String fileName, long period) {
removeFileChangeListener(listener, fileName);
FileMonitorTask task = new FileMonitorTask(listener, fileName);
timerTasks.put(fileName + listener.hashCode(), task);
timer.schedule(task, period, period);
}
private void notifyListeners() {
final Properties properties = new Properties(this);
for (FileChangeListener aListener : listeners) {
aListener.notifyFileChanged(properties);
}
}
