### Question:
SiteMapExtractorImpl extends SiteMapExtractorBase { @Override protected UrlExternalizer getUrlExternalizer() { return Optional.ofNullable(super.getUrlExternalizer()) .orElse(urlExternalizer); } SiteMapExtractorImpl(final SiteMapConfiguration configuration,
                                final SiteMapUrlBuilder urlBuilder,
                                final UrlExternalizer urlExternalizer,
                                final PropertyProvider... propertyProviders); @Override SiteMapConfiguration getConfiguration();  }### Answer:
@Test public void getExternalizer() { assertEquals(externalizer, model.getUrlExternalizer()); when(config.getUrlExternalizer()).thenReturn(mock(UrlExternalizer.class)); assertNotEquals(externalizer, model.getUrlExternalizer()); }