### Question:
DataTypeListHighlightHelper { public void highlight(final Element element) { cleanHighlightClass(); element.classList.add(HIGHLIGHT); } @Inject  DataTypeListHighlightHelper(final DataTypeUtils dataTypeUtils); void init(final DataTypeList dataTypeList); void highlightLevel(final Element element); void highlight(final Element element); void cleanHighlightClass(); void cleanLevelHighlightClass(); DataTypeList getDataTypeList();  }### Answer:
@Test public void testHighlight() { final Element element = mock(Element.class); element.classList = mock(DOMTokenList.class); doNothing().when(helper).cleanHighlightClass(); helper.highlight(element); verify(helper).cleanHighlightClass(); verify(element.classList).add(HIGHLIGHT); }