public boolean removeAll(final Collection<?> coll)
    {
        boolean removed = false;

        for (final Object value : coll)
        {
            removed |= remove(value);
        }

        return removed;
    }
@Test
    void removingEmptySetDoesNothing()
    {
        addTwoElements(testSet);

        assertFalse(testSet.removeAll(new IntHashSet(100)));
        assertFalse(testSet.removeAll(new HashSet<Integer>()));
        assertContainsElements(testSet);
    }