A (considering it's java) compact quicksort implementation for a double linked list.

DLL Quicksort

	private void sort(ListElement l, ListElement r, DoublyLinkedList in) {
		ListElement LastMoved = r;
		ListElement FirstNotMoved = null;
		while (l != r) {
			ListElement next = l.next;
			if (l.getKey() > r.getKey()) {
				move(l, LastMoved, in);
				LastMoved = l;
			} else if (FirstNotMoved == null)
				FirstNotMoved = l;
			l = next;
		}
		if (FirstNotMoved != null)	sort(FirstNotMoved, r.prev, in);
		if (r != LastMoved)	sort(r.next, LastMoved, in);
	}
	private void move(ListElement f, ListElement p, DoublyLinkedList in) {
		if (in.first == f)in.first = f.next;
		f.next.prev = f.prev;
		f.prev.next = f.next;
		f.next = p.next;
		f.prev = p;
		p.next.prev = p.next = f;
	}