@Test (expected = IllegalArgumentException.class)
public void testInvalidURL() throws Exception {

    final String nifiUrl = "not a url";
    Map<String,String> configs = new HashMap<>();
    configs.put(NiFiConfigs.NIFI_URL, nifiUrl);
    configs.put(NiFiConfigs.NIFI_AUTHENTICATION_TYPE, NiFiAuthType.NONE.name());
    NiFiConnectionMgr.getNiFiClient("nifi", configs);
}