public void testSubSetContents2() {
COWNavigableSet set = set5();
SortedSet sm = set.subSet(two, three);
assertEquals(1, sm.size());
assertEquals(two, sm.first());
assertEquals(two, sm.last());
assertFalse(sm.contains(one));
assertTrue(sm.contains(two));
assertFalse(sm.contains(three));
assertFalse(sm.contains(four));
assertFalse(sm.contains(five));