SortedMap sub = sm.subMap(fromKey, toKey);
assertEquals(2, sub.size());
assertEquals(true, sm.containsKey(first));
assertEquals(false, sub.containsKey(first));
assertEquals(true, sm.containsValue(firstValue));
assertEquals(false, sub.containsValue(firstValue));
assertEquals(true, sm.containsKey(fromKey));
assertEquals(true, sub.containsKey(fromKey));
assertEquals(true, sm.containsValue(fromKeyValue));
assertEquals(true, sub.containsValue(fromKeyValue));
assertEquals(true, sm.containsKey(second));