question: @ Override public void command ( ) { try { createSchemaWatcher ( ) ; updateSchema ( null , - 1 ) ; } catch ( Exception exc ) { log . error ( "Failed to update managed-schema watcher after session expiration due to: " + exc , exc ) ; } }
target:  Called after a ZooKeeper session expiration occurs; need to re-create the watcher and update the current schema from ZooKeeper.