public synchronized void stop() throws IOException {
if (worker == null) {
throw new IllegalStateException("FileSystemWatcher is not started."); // NOI18N
}
assert rtData != null;
assert rtData.length == 2;
assert rtData[0] != null;
assert rtData[1] != null;
cs.FSEventStreamStop(rtData[0]);
cs.FSEventStreamInvalidate(rtData[0]);
cs.FSEventStreamRelease(rtData[0]);
cf.CFRunLoopStop(rtData[1]);
worker.shutdown();
worker = null;
rtData = null;
}
