@Test
public void testUpdLoaderInvalid() {

    ZpeUpdPolLoader loaderMock = Mockito.mock(ZpeUpdPolLoader.class);
    Mockito.when(loaderMock.getDirName()).thenReturn(null);
    ZpeUpdMonitor monitor = new ZpeUpdMonitor(loaderMock);
            
    // TODO: validate log message
    monitor.run();
    monitor.cancel();
    monitor.run();
}