@Test
public void testEmptyDelegationToken() throws IOException {

  Configuration conf = getTestConfiguration();
  MiniDFSCluster cluster = null;
  try {
    cluster = new MiniDFSCluster.Builder(conf).numDataNodes(1).build();
    FileSystem fileSys = cluster.getFileSystem();
    fileSys.getDelegationToken("");
  } finally {
    cluster.shutdown();
  }
}