[ZOOKEEPER-1910] RemoveWatches wrongly removes the watcher if multiple watches exists on a path

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Fixed
• Fix Version/s: 3.5.0
• Component/s: java client, server
• Labels: remove_watches
• Assignee: Rakesh Radhakrishnan
• Reporter: Rakesh Radhakrishnan
• Created: 11/Apr/14 08:08
• Updated: 04/Mar/23 03:36
• Resolved: 29/Apr/14 02:31

Description

Consider a case where zkclient has added 2 data watchers(say 'w1' and 'w2') on '/node1'.

Now user has removed w1, but this is deleting the 'CnxnWatcher' in ZK server against the "/node1" path. This will affect other data watchers(if any) of same client on same path. In our case 'w2' would not be notified.

Note: please see the attached test case to understand more.

Issue Links

• causes: ZOOKEEPER-4625 No reliable way to remove watcher without interfering others in same watch mode and on same path
• is related to: ZOOKEEPER-442 need a way to remove watches that are no longer of interest
• is related to: ZOOKEEPER-2586 zoo_aremove_watchers() does not remove a watch of path has more than one watch
• relates to: ZOOKEEPER-1919 Update the C implementation of removeWatches to have it match ZOOKEEPER-1910