DocumentTraversal contains methods that create
NodeIterators and
TreeWalkers to traverse a node and its children in document order (depth first, pre-order traversal, which is equivalent to the order in which the start tags occur in the text representation of the document).
NodeIterators are used to step through a set of nodes, e.g.
TreeWalker objects are used to navigate a document tree or subtree using the view of the document defined by their
whatToShow flags and filter (if any).