public PrimaryKey getHashKey() {
        return hashKey;
    }
@Test
    public void testEqualsWithKeys() {
        {
            HollowSetSchema s1 = new HollowSetSchema("Test", "TypeA", "f1");
            HollowSetSchema s2 = new HollowSetSchema("Test", "TypeA", "f1");

            Assert.assertEquals(s1, s2);
            Assert.assertEquals(s1.getHashKey(), s2.getHashKey());
            Assert.assertEquals(new PrimaryKey("TypeA", "f1"), s2.getHashKey());
        }

        {
            HollowSetSchema s1 = new HollowSetSchema("Test", "TypeA", "f1", "f2");
            HollowSetSchema s2 = new HollowSetSchema("Test", "TypeA", "f1", "f2");

            Assert.assertEquals(s1, s2);
            Assert.assertEquals(s1.getHashKey(), s2.getHashKey());
            Assert.assertEquals(new PrimaryKey("TypeA", "f1", "f2"), s2.getHashKey());
        }

        {
            HollowSetSchema s1 = new HollowSetSchema("Test", "TypeA");
            HollowSetSchema s2 = new HollowSetSchema("Test", "TypeA", "f1");

            Assert.assertNotEquals(s1, s2);
            Assert.assertNotEquals(s1.getHashKey(), s2.getHashKey());
        }

        {
            HollowSetSchema s1 = new HollowSetSchema("Test", "TypeA", "f1");
            HollowSetSchema s2 = new HollowSetSchema("Test", "TypeA", "f1", "f2");

            Assert.assertNotEquals(s1, s2);
            Assert.assertNotEquals(s1.getHashKey(), s2.getHashKey());
        }
    }