@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);
  }
}

@ 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 ) ; } }
called after a zookeeper session expiration occurs ; need to re - create the watcher and update the current schema from zookeeper .
