### Question:
SeLionElementSet extends LinkedHashSet<SeLionElement> { public SeLionElement findMatch(String element) { if (!StringUtils.isEmpty(element)) { Optional<SeLionElement> first = stream().filter(eachElement -> eachElement.looksLike(element)).findFirst(); return first.orElse(null); } return null; } SeLionElementSet();  SeLionElementSet(SeLionElement[] elements);  SeLionElementSet(Collection<SeLionElement> elements); SeLionElement findMatch(String element); boolean isValid(String element); boolean isValidUIElement(String element); boolean isExactMatch(String element); abstract boolean add(String element); boolean add(SeLionElement element);  }### Answer:
@Test public void testFindMatch() { SeLionElement expected = new SeLionElement("com.foo.Bar"); SeLionElementSet elementSet = new DummySeLionElementSet(new SeLionElement[] { expected }); SeLionElement match = elementSet.findMatch("Bar"); assertSame(match, expected); match = elementSet.findMatch("Baz"); assertNull(match); }