@Override
    public int hashCode() {
        int hashCode = 0;
        for (int hash : hashes) {
            hashCode += hash;
        }
        return hashCode;
    }
@Test
    public void testHashCode() {
        final OAHashSet<Integer> set = new OAHashSet<>(8);
        populateSet(set, 10);

        final int expectedHashCode = 45;

        assertEquals(expectedHashCode, set.hashCode());

    }