Hi ZK Devs, A few months ago I create a PR for gracefully handling null default watcher[1]. After some discussion it seems we reach a consensus that
1. Forbid require default watcher (boolean watcher=true) if default watcher is null. 2. Exclude null default watcher from materialize watches which cause NPE in ClientCnxn.EventThread#processEvent Though, it stalls for quite a bit and I'd like to throw it into mailing list and request for reviews. Feedback is appreciated! Best, tison. [1] https://github.com/apache/zookeeper/pull/1120
