[CURATOR-437] zookeeper connection leak when session expires.

https://github.com/apache/curator/blob/master/curator-client/src/main/java/org/apache/curator/utils/InjectSessionExpiration.java#L97

Curator inject will set zookeeper state to CLOSED when session expires without close zk associated threads.

If state set to CLOSED, ZooKeeper.close() function won't be able to release resources properly, which lead to memory and connection leak.

To reproduce, create a curator client, then shutdown zk server, wait for session timeout, restart the zk server. There will be two ZooKeeper instances and two connections to the server.

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Originally reported by zealot0630, imported from: zookeeper connection leak when session expires.

• status: Open
  
• priority: Major
  
• resolution: Unresolved
  
• imported: 2025-01-21