public abstract Optional<Long> maxPartitionRefreshTs();
@Test
    public void testMaxPartitionRefreshTs() {

        Map<String, PartitionInfo> fakePartitionInfo = new HashMap<>();
        Partition p1 = new Partition("p1", 100);
        Partition p2 = new Partition("p2", 200);
        fakePartitionInfo.put("p1", p1);
        fakePartitionInfo.put("p2", p2);
        new MockUp<DefaultTraits>() {
            @Mock
            public Map<String, PartitionInfo> getPartitionNameWithPartitionInfo() {
                return fakePartitionInfo;
            }
        };

        Optional<Long> result = new PaimonPartitionTraits().maxPartitionRefreshTs();
        Assert.assertTrue(result.isPresent());
        Assert.assertEquals(200L, result.get().longValue());
    }