@Override
        public ProtocolType call() throws Exception {
          return createProxy(nodeId, nodeToken);
        }
@param nodeId Hostname + post.
@param nodeToken A custom node token. If not specified, the default token is used.
@return the protocol client implementation for the node.
llap-common/src/java/org/apache/hadoop/hive/llap/AsyncPbRpcProxy.java