Examples of java.util.NavigableMap.descendingKeySet()

java.util.NavigableMap.descendingKeySet()

Returns a reverse order {@link NavigableSet} view of the keys contained in this map.The set's iterator returns the keys in descending order. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator's own {@code remove} operation), the results of the iteration are undefined. Theset supports element removal, which removes the corresponding mapping from the map, via the {@code Iterator.remove}, {@code Set.remove}, {@code removeAll}, {@code retainAll}, and {@code clear} operations.It does not support the {@code add} or {@code addAll} operations. @return a reverse order navigable set view of the keys in this map

        Iterator i = sm.keySet().iterator();
        Object k;
        k = (Integer)(i.next());
        assertEquals(two, k);
        assertFalse(i.hasNext());
        Iterator r = sm.descendingKeySet().iterator();
        k = (Integer)(r.next());
        assertEquals(two, k);
        assertFalse(r.hasNext());


        Iterator j = sm.keySet().iterator();

        k = (Integer)(i.next());
        assertEquals(four, k);
        k = (Integer)(i.next());
        assertEquals(five, k);
        assertFalse(i.hasNext());
        Iterator r = sm.descendingKeySet().iterator();
        k = (Integer)(r.next());
        assertEquals(five, k);
        k = (Integer)(r.next());
        assertEquals(four, k);
        k = (Integer)(r.next());

        k = (Integer)(i.next());
        assertEquals(two, k);
        k = (Integer)(i.next());
        assertEquals(three, k);
        assertFalse(i.hasNext());
        Iterator r = sm.descendingKeySet().iterator();
        k = (Integer)(r.next());
        assertEquals(three, k);
        k = (Integer)(r.next());
        assertEquals(two, k);
        assertFalse(r.hasNext());

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