code: AbstractJcrNode node( NodeKey nodeKey,
                            AbstractJcrNode.Type expectedType ) throws ItemNotFoundException {
          return node(nodeKey, expectedType, null);
      }
docs: Obtain the {@link Node JCR Node} object for the node with the supplied key.
  
  @param nodeKey the node's key
  @param expectedType the expected implementation type for the node, or null if it is not known
  @return the JCR node; never null
  @throws ItemNotFoundException if there is no node with the supplied key