### Question:
AboutViewModel implements ViewModel { public void onLinkClicked(String linkText) { if (libraryLinkMap.containsKey(linkText)) { onLinkClickedHandler.accept(libraryLinkMap.get(linkText)); } } AboutViewModel(); @PostConstruct void initLibraryMap(); void onLinkClicked(String linkText); ReadOnlyStringProperty librariesLabelTextProperty();  }### Answer:
@Test public void testOnLinkClicked() { viewModel.libraryLinkMap.put(MY_COOL_LIB_NAME, MY_COOL_LIB_URL); viewModel.libraryLinkMap.put(OTHER_FX_NAME, OTHER_FX_URL); viewModel.onLinkClicked(MY_COOL_LIB_NAME); verify(onLinkClickedHandler).accept(MY_COOL_LIB_URL); viewModel.onLinkClicked(OTHER_FX_NAME); verify(onLinkClickedHandler).accept(OTHER_FX_URL); viewModel.onLinkClicked("something else"); verifyNoMoreInteractions(onLinkClickedHandler); }