public static String nodePath()

in velocity-tools-generic/src/main/java/org/apache/velocity/tools/XmlUtils.java [456:559]
80 lines of code
20 McCabe index (conditional complexity)

    public static String nodePath(Node n)
    {
        // abort early
        if (null == n)
            return null;

        // declarations
        Node parent = null;
        Stack<Node> hierarchy = new Stack<Node>();
        StringBuffer buffer = new StringBuffer('/');

        // push element on stack
        hierarchy.push(n);

        switch (n.getNodeType()) {
            case Node.ATTRIBUTE_NODE:
                parent = ((Attr) n).getOwnerElement();
                break;
            case Node.COMMENT_NODE:
            case Node.ELEMENT_NODE:
            case Node.DOCUMENT_NODE:
                parent = n.getParentNode();
                break;
            default:
                throw new IllegalStateException("Unexpected Node type" + n.getNodeType());
        }

        while (null != parent && parent.getNodeType() != Node.DOCUMENT_NODE) {
            // push on stack
            hierarchy.push(parent);

            // get parent of parent
            parent = parent.getParentNode();
        }

        // construct xpath
        Object obj = null;
        while (!hierarchy.isEmpty() && null != (obj = hierarchy.pop())) {
            Node node = (Node) obj;
            boolean handled = false;

            if (node.getNodeType() == Node.ELEMENT_NODE)
            {
                Element e = (Element) node;

                // is this the root element?
                if (buffer.length() == 1)
                {
                    // root element - simply append element name
                    buffer.append(node.getNodeName());
                }
                else
                {
                    // child element - append slash and element name
                    buffer.append("/");
                    buffer.append(node.getNodeName());

                    if (node.hasAttributes())
                    {
                        // see if the element has a name or id attribute
                        if (e.hasAttribute("id"))
                        {
                            // id attribute found - use that
                            buffer.append("[@id='" + e.getAttribute("id") + "']");
                            handled = true;
                        }
                        else if (e.hasAttribute("name"))
                        {
                            // name attribute found - use that
                            buffer.append("[@name='" + e.getAttribute("name") + "']");
                            handled = true;
                        }
                    }

                    if (!handled)
                    {
                        // no known attribute we could use - get sibling index
                        int prev_siblings = 1;
                        Node prev_sibling = node.getPreviousSibling();
                        while (null != prev_sibling)
                        {
                            if (prev_sibling.getNodeType() == node.getNodeType())
                            {
                                if (prev_sibling.getNodeName().equalsIgnoreCase(
                                    node.getNodeName()))
                                {
                                    prev_siblings++;
                                }
                            }
                            prev_sibling = prev_sibling.getPreviousSibling();
                        }
                        buffer.append("[" + prev_siblings + "]");
                    }
                }
            }
            else if (node.getNodeType() == Node.ATTRIBUTE_NODE)
            {
                buffer.append("/@");
                buffer.append(node.getNodeName());
            }
        }
        // return buffer
        return buffer.toString();
    }