@Override
    public void remove()
    {
        throw new UnsupportedOperationException();
    }
@Test
    void removeUnsupported()
    {
        PDOutlineItemIterator pdOutlineItemIterator = new PDOutlineItemIterator(new PDOutlineItem());
        assertThrows(UnsupportedOperationException.class, () -> pdOutlineItemIterator.remove());
    }