/** Callbacks from zkClient */
@Override
public void connectionDown() {
List<CoordinateListener> coordinateListenerListCopy = new ArrayList<CoordinateListener>();
synchronized (coordinateListenerList) {
coordinateListenerListCopy.addAll(coordinateListenerList);
}
for (CoordinateListener coordinateListener : coordinateListenerListCopy) {
coordinateListener.onCoordinateEvent(
CoordinateListener.Event.NO_CONNECTION_TO_STORAGE, "down");
}
isSynchronizedWithZooKeeper.set(false);
}
/**
* Sends an event too all coordinate listeners. Note that the event is sent from this thread so if
* the callback code does the wrong calls, deadlocks might occur.
*
* @param event
* @param message
*/
private void sendEventToCoordinateListener(
final CoordinateListener.Event event, final String message) {
synchronized (callbacksMonitor) {
LOG.fine("Event " + event.name() + " " + message);
List<CoordinateListener> coordinateListenerListCopy = new ArrayList<CoordinateListener>();
synchronized (coordinateListenerList) {
coordinateListenerListCopy.addAll(coordinateListenerList);
}
for (CoordinateListener listener : coordinateListenerListCopy) {
listener.onCoordinateEvent(event, message);
}
}
}
/**
* Registers a coordinatelistener that will receive events when there are changes to the status
* node. Don't do any heavy lifting in the callback and don't call cloudname from the callback as
* this might create a deadlock.
*
* @param coordinateListener
*/
public void registerCoordinateListener(final CoordinateListener coordinateListener) {
String message = "New listener added, resending current state.";
synchronized (callbacksMonitor) {
coordinateListenerList.add(coordinateListener);
if (isSynchronizedWithZooKeeper.get()) {
coordinateListener.onCoordinateEvent(CoordinateListener.Event.COORDINATE_OK, message);
}
}
}