@Test
public void testIterator() {

    SequenceSet set = new SequenceSet();
    set.add(new Sequence(0, 2));
    set.add(new Sequence(4, 5));
    set.add(new Sequence(7));
    set.add(new Sequence(20, 21));
    long expected[] = new long[]{0, 1, 2, 4, 5, 7, 20, 21};
    int index = 0;
    Iterator<Long> iterator = set.iterator();
    while(iterator.hasNext()) {
        assertEquals(expected[index++], iterator.next().longValue());
    }
}