### Question:
CellEditorControlsViewImpl implements CellEditorControlsView { void focusOnDMNContainer(final Object o) { final Element element = getDMNContainer(); if (!Objects.isNull(element)) { element.focus(); } } CellEditorControlsViewImpl(); @Inject  CellEditorControlsViewImpl(final Document document,
                                      final Div cellEditorControls,
                                      final Div cellEditorControlsContainer); Optional<PopupEditorControls> getActiveEditor(); void setActiveEditor(final Optional<PopupEditorControls> activeEditor); @PostConstruct void setup(); @PreDestroy void destroy(); @Override void show(final PopupEditorControls editor,
                     final int x,
                     final int y); @Override void hide(); static final String LEFT; static final String TOP; }### Answer:
@Test public void testFocusOnDMNContainer() { final elemental2.dom.Element dmnContainerElement = mock(elemental2.dom.Element.class); doReturn(dmnContainerElement).when(view).getDMNContainer(); view.focusOnDMNContainer(null); verify(dmnContainerElement).focus(); }