### Question:
BaseMobileSeLionElementSet extends SeLionElementSet { public boolean add(String element) { return super.add(new SeLionElement(element)); } BaseMobileSeLionElementSet(Collection<SeLionElement> elements); List<GUIObjectDetails> getGUIObjectList(List<String> keys); boolean add(String element);  }### Answer:
@Test public void testAdd() { SeLionElementSet elementSet = new BaseMobileSeLionElementSet(Collections.emptyList()); assertEquals(elementSet.size(), 0); elementSet.add("com.foo.BaseMobileSeLionElementSetTest"); Optional<SeLionElement> first = elementSet.stream().findFirst(); assertEquals(first.orElse(null).getElementClass(),"BaseMobileSeLionElementSetTest" , "the custom added element is not first"); }