@Test public void testFirstOfType() { Collection<A> collection = new HashSet<A>(); collection.add(new B()); collection.add(new B()); assertTrue(Groups.firstOfType(C.class, collection) == null); assertTrue(collection.contains(Groups.firstOfType(A.class, collection))); assertTrue(collection.contains(Groups.firstOfType(B.class, collection))); }
@Test public void testFirstEmpty() { Collection<String> collection = new HashSet<String>(); assertTrue(Groups.first(collection) == null); collection.add("Hello World"); assertTrue(Groups.first(collection).equals("Hello World")); collection.add("Goodbye World"); assertTrue(collection.contains(Groups.first(collection))); }