Descending Iterator and Adapter pattern

There is a descending iterator in linked list implementation in Java SDK. A humble private class in LinkedList. A good example of adapter.

	LinkedList<String> linkList = new LinkedList<String>();//can't have a size...!
	linkList.add("a");
	linkList.addFirst("b");
	linkList.addLast("c");
	System.out.println(linkList);
	Iterator<String> descendingIterator = linkList.descendingIterator();
	while(descendingIterator.hasNext()){
	System.out.println(descendingIterator.next());
	}

view raw link-1.java hosted with ❤ by GitHub

calls up


public Iterator<E> descendingIterator() {
return new DescendingIterator();
}

	/** Adapter to provide descending iterators via ListItr.previous */
	private class DescendingIterator implements Iterator {
	final ListItr itr = new ListItr(size());
	public boolean hasNext() {
	return itr.hasPrevious();
	}
	public E next() {
	return itr.previous();
	}
	public void remove() {
	itr.remove();
	}
	}

view raw desc.java hosted with ❤ by GitHub