public  void add(E e) 
{
            throw new UnsupportedOperationException();
}

Not supported. Always throws UnsupportedOperationException.

 public boolean hasNext() 
{
            return cursor <  snapshot.length;
}

 public boolean hasPrevious() 
{
            return cursor  > 0;
}

 public E next() 
{
            if (! hasNext())
                throw new NoSuchElementException();
            return (E) snapshot[cursor++];
}

 public int nextIndex() 
{
            return cursor;
}

 public E previous() 
{
            if (! hasPrevious())
                throw new NoSuchElementException();
            return (E) snapshot[--cursor];
}

 public int previousIndex() 
{
            return cursor-1;
}

 public  void remove() 
{
            throw new UnsupportedOperationException();
}

Not supported. Always throws UnsupportedOperationException.

 public  void set(E e) 
{
            throw new UnsupportedOperationException();
}

Not supported. Always throws UnsupportedOperationException.