### Question:
TinySet extends AbstractProxySet<E> { @Override public void clear() { mySet = Collections.emptySet(); }  static Set<T> add(Set<T> input, T e); static Set<T> addAll(Set<T> input, Collection<? extends T> c); static Set<T> remove(Set<T> set, Object o); static Set<T> removeAll(Set<T> set, Collection<T> c); static Set<T> retainAll(Set<T> mySet, Collection<?> c); @Override boolean add(E e); @Override boolean addAll(Collection<? extends E> c); @Override void clear(); @Override boolean remove(Object o); @Override boolean removeAll(Collection<?> c); @Override boolean retainAll(Collection<?> c);  }### Answer:
@Test public void testClear() { TinySet<Object> set = new TinySet<>(); set.clear(); checkSize0(set); Assert.assertTrue(set.add(TEST_OBJ1)); checkSize1(set); set.clear(); checkSize0(set); Assert.assertTrue(set.addAll(Arrays.asList(TEST_OBJ1, TEST_OBJ2, TEST_OBJ3))); checkSizeN(set, 3); set.clear(); checkSize0(set); }