final Server server = new RPC.Builder(conf)
.setProtocol(ClientProtocol.class).setInstance(mockNN)
.setBindAddress(ADDRESS).setPort(0).setNumHandlers(5).setVerbose(true)
.setSecretManager(sm).build();
server.start();
final UserGroupInformation current = UserGroupInformation.getCurrentUser();
final InetSocketAddress addr = NetUtils.getConnectAddress(server);
String user = current.getUserName();
Text owner = new Text(user);