### Question:
SeLionElementSet extends LinkedHashSet<SeLionElement> { public boolean isValid(String element) { return findMatch(element) != 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 testIsValid() { SeLionElement element = new SeLionElement("com.foo.Bar"); SeLionElementSet elementSet = new DummySeLionElementSet(new SeLionElement[] { element }); assertTrue(elementSet.isValid("Bar")); assertFalse(elementSet.isValid("Baz")); }