### Question:
LinkedTreeSet extends AbstractSet<E> { @Override public boolean removeAll(Collection<?> c) { return super.removeAll(new LinkedTreeSet<>(c)); } LinkedTreeSet();  LinkedTreeSet(Collection<? extends E> other); @Override boolean add(E e); @Override boolean remove(Object o); @Override boolean removeAll(Collection<?> c); @Override boolean retainAll(Collection<?> c); @Override void clear(); @Override boolean contains(Object o); @Override Iterator<E> iterator(); @Override int hashCode(); @Override boolean equals(Object o); @Override int size(); @Override String toString();  }### Answer:
@Test void testRemoveAll() throws Exception { Set<Object> set = new LinkedTreeSet<>(); assertThat(set.removeAll(Arrays.asList(2, -0.0))).isFalse(); set.add(1.0); set.add(0); set.add(2); assertThat(set.removeAll(Arrays.asList(3, -0.0))).isTrue(); assertThat(set.removeAll(Arrays.asList(3, -0.0))).isFalse(); assertThat(set).containsExactly(1.0, 2); set.clear(); set.add(1.0); set.add(-0.0); set.add(2); set.removeAll(Arrays.asList(0, 2.0)); assertThat(set).containsExactly(1.0); }
@Test void testSizeAfterRemoveAll() throws Exception { Set<Object> set = new LinkedTreeSet<>(Arrays.asList("A", "B")); set.removeAll(Arrays.asList("B", "C", "D")); assertThat(set).containsExactly("A"); assertThat(set).hasSize(1); }