public void testCeilingEntry() {
ConcurrentNavigableMap map = map5();
Map.Entry e1 = map.ceilingEntry(three);
assertEquals(three, e1.getKey());
Map.Entry e2 = map.ceilingEntry(zero);
assertEquals(one, e2.getKey());
Map.Entry e3 = map.ceilingEntry(five);
assertEquals(five, e3.getKey());