private String getHostIdentifier(String hostname, int port) {
    StringBuilder sb = new StringBuilder();
    try {
      InetAddress inetAddress = InetAddress.getByName(hostname);
      sb.append(inetAddress.getHostAddress()).append(":");
    } catch (UnknownHostException e) {
      // ignore
      LOG.warn("Unable to determine IP address for host: {}.. Ignoring..", hostname, e);
    }
    sb.append(hostname).append(":").append(port);
    return sb.toString();
  }
@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