@Override
    public void stateChanged(final CuratorFramework curatorFramework, final ConnectionState connectionState) {
      LOG.info("Connection state change notification received. State: {}", connectionState);
    }
Get the ensemble server addresses from the configuration. The format is: host1:port,
host2:port..

@param conf configuration
llap-client/src/java/org/apache/hadoop/hive/registry/impl/ZkRegistryBase.java