public void test_AscendingSubMap_descendingMap() {
NavigableMap descendingMap = navigableMap_startExcluded_endExcluded
.descendingMap();
assertEquals(navigableMap_startExcluded_endExcluded.size(),
descendingMap.size());
assertNotNull(descendingMap.comparator());
assertEquals(navigableMap_startExcluded_endExcluded.firstKey(),
descendingMap.lastKey());
assertEquals(navigableMap_startExcluded_endExcluded.firstEntry(),
descendingMap.lastEntry());