### Question:
EmptyIntSet extends AbstractImmutableIntSet { @Override public boolean containsAll(IntSet set) { return set.isEmpty(); }  static IntSet getInstance(); @Override boolean contains(int i); @Override boolean containsAll(IntSet set); @Override int size(); @Override boolean isEmpty(); @Override boolean contains(Object o); @Override PrimitiveIterator.OfInt iterator(); @Override Object[] toArray(); @Override T[] toArray(T[] a); @Override boolean containsAll(Collection<?> c); @Override IntStream intStream(); @Override boolean equals(Object obj); @Override String toString();  }### Answer:
@Test public void testContainsAll1() throws Exception { Set<Integer> hashSet = new HashSet<>(); hashSet.add(3); assertFalse(es.containsAll(hashSet)); assertTrue(hashSet.containsAll(es)); hashSet.remove(3); assertTrue(hashSet.containsAll(es)); assertTrue(es.containsAll(hashSet)); }
@Test public void testContainsAll() throws Exception { IntSet sis2 = new SingletonIntSet(3); assertFalse(es.containsAll(sis2)); assertTrue(sis2.containsAll(es)); IntSet sis3 = new RangeSet(0); assertTrue(sis3.containsAll(es)); assertTrue(es.containsAll(sis3)); }