code: public static SiblingCounter create( final CachedNode node,
                                           final NodeCache cache ) {
          assert node != null;
          assert cache != null;
          return new SiblingCounter() {
              @Override
              public int countSiblingsNamed( Name childName ) {
                  return node.getChildReferences(cache).getChildCount(childName);
              }
          };
      }
docs: Creates a sibling counter that lazily obtains a {@link ChildReferences}.
  
  @param node the node; may not be null
  @param cache the cache; may not be null
  @return the sibling counter; never null