@Test
public void testShowConfig() {

  ConfigType configType = mock(ConfigType.class);
  Map<String, Map<String, String>> mockResult = mock(Map.class);
  when(configType.getName()).thenReturn(CORE_SITE);
  when(client.getServiceConfigMap(anyString())).thenReturn(mockResult);
  when(mockResult.get(CORE_SITE)).thenReturn(new HashMap<String, String>());
  configCommands.showConfig(configType);
  verify(client).getServiceConfigMap(CORE_SITE);
}