For CHILD_ADDED and CHILD_UPDATED events you will always get the data for the node, but there's no guarantee that the node is actually going to have data. If some other application (or person) created a zNode under the cache's path without data this would potentially break your application, so it's probably best to go on the defensive side and handle both cases. cheers
On Wed, Jun 10, 2015 at 10:36 AM, Zhang Xiaoyu <[email protected]> wrote: > Hi, guys, > I am trying to use PathChildrenCache to set up a watcher on a ZK path, so > when any children is added to the path, I will get a watcher event. > > My client logic is in the watcher event, do getData().getData() to get the > children's data. This is working for me. The question is can I always relay > on this or should I have a backup option if data is a empty byte[], I still > retrieval data based on child's path ? > > My logic in watcher event is: > > if (data.length != 0) { > //do the following logic > } else { > byte[] data = client.getData().forPatch(childPath); > // do the following logic > } > > do I need the else block ? Let me know if need more code explanation. > > Thanks, > Johnny >
