I've updated based on the last round of feedback regarding ZK operation: http://pastebin.com/f66898b7
This is what I think the API should look like for event based applications without any insane requirements. You write code like: NodeListener listener = new NodeListener() { public void onData( String path, Stat stat, byte[] data ) { System.out.printf( "event: onData path: %s, version: %s, data: %s\n", path, stat.getVersion(), new String( data ) ); } public void onKeeperException( KeeperException e ) { System.out.printf( "event: onKeeperException: \n" ); e.printStackTrace(); } public void onFailure() { System.out.printf( "event: onFailure\n" ); } public void onConnect() { System.out.printf( "event: onConnect\n" ); } }; NodeWatcher nWatcher = new NodeWatcher( "server45.example.com:2181, server46.example.com:2181,server47.example.com:2181", listener ); nWatcher.watch( "/foo" ); nWatcher.poll(); .... and then you will receive events back from ZK when the files are updated. I believe it handles all race and fail conditions of ZK which was the hard part since some of these are subtle or not really documented. I'd be willing to contrib this if others found it useful. I think we're going to use it as our main interface to ZK since it solves all the issues I care about. Kevin -- Founder/CEO Spinn3r.com Location: San Francisco, CA AIM/YIM: sfburtonator Skype: burtonator Work: http://spinn3r.com