public static List<String> sortSimpleName(List<String> list) {
        if (list != null && list.size() > 0) {
            Collections.sort(list, SIMPLE_NAME_COMPARATOR);
        }
        return list;
    }
@Test
    void testSortSimpleName() {
        List<String> list = new ArrayList<String>();
        list.add("aaa.z");
        list.add("b");
        list.add(null);
        list.add("zzz.a");
        list.add("c");
        list.add(null);

        List<String> sorted = CollectionUtils.sortSimpleName(list);
        assertNull(sorted.get(0));
        assertNull(sorted.get(1));
    }