### Question:
KieMultipleSelectElement implements KieSelectElementBase { public void onChange() { this.onChange.accept(getValue()); } @Inject  KieMultipleSelectElement(final View view,
                                    final KieSelectOptionsListPresenter optionsListPresenter,
                                    final Elemental2DomUtil elemental2DomUtil); @PostConstruct void init(); void setup(final Element element,
                      final List<KieSelectOption> options,
                      final List<String> initialValue,
                      final Consumer<List<String>> onChange); void onChange(); void setValue(final List<String> value); List<String> getValue();  }### Answer:
@Test public void testOnChange() { final AtomicInteger i = new AtomicInteger(0); doReturn(Arrays.asList("value1", "value2")).when(kieSelectElement).getValue(); kieSelectElement.onChange = value -> { assertEquals(Arrays.asList("value1", "value2"), value); i.incrementAndGet(); }; kieSelectElement.onChange(); assertEquals(1, i.get()); }