+ /**
+ * Writing subtree filter specified by parent {@link YangInstanceIdentifier} and specific fields
+ * into {@link Element}. Field paths are relative to parent query path. Filter is created without following
+ * {@link EffectiveModelContext}.
+ *
+ * @param query path to the root node
+ * @param fields list of specific fields for which the filter should be created
+ * @param filterElement XML filter element to which the created filter will be written
+ */
+ public static void writeSchemalessFilter(final YangInstanceIdentifier query,
+ final List<YangInstanceIdentifier> fields, final Element filterElement) {
+ pathArgumentTreeToXmlStructure(constructPathArgumentTree(query, aggregateFields(fields)), filterElement);
+ }
+
+ private static void pathArgumentTreeToXmlStructure(final PathNode pathArgumentTree, final Element data) {
+ final PathArgument pathArg = pathArgumentTree.element();
+
+ final QName nodeType = pathArg.getNodeType();
+ final String elementNamespace = nodeType.getNamespace().toString();
+
+ if (data.getElementsByTagNameNS(elementNamespace, nodeType.getLocalName()).getLength() != 0) {
+ // element has already been written as list key
+ return;
+ }
+
+ final Element childElement = data.getOwnerDocument().createElementNS(elementNamespace, nodeType.getLocalName());
+ data.appendChild(childElement);
+ if (pathArg instanceof NodeIdentifierWithPredicates nip) {
+ appendListKeyNodes(childElement, nip);
+ }
+ for (final PathNode childrenNode : pathArgumentTree.children()) {
+ pathArgumentTreeToXmlStructure(childrenNode, childElement);
+ }
+ }
+
+ /**
+ * Appending list key elements to parent element.
+ *
+ * @param parentElement parent XML element to which children elements are appended
+ * @param listEntryId list entry identifier
+ */
+ public static void appendListKeyNodes(final Element parentElement, final NodeIdentifierWithPredicates listEntryId) {
+ for (Entry<QName, Object> key : listEntryId.entrySet()) {
+ final Element keyElement = parentElement.getOwnerDocument().createElementNS(
+ key.getKey().getNamespace().toString(), key.getKey().getLocalName());
+ keyElement.setTextContent(key.getValue().toString());
+ parentElement.appendChild(keyElement);
+ }
+ }
+
+ /**
+ * Aggregation of the fields paths based on parenthesis. Only parent/enclosing {@link YangInstanceIdentifier}
+ * are kept. For example, paths '/x/y/z', '/x/y', and '/x' are aggregated into single field path: '/x'
+ *
+ * @param fields paths of fields
+ * @return filtered {@link List} of paths
+ */
+ private static List<YangInstanceIdentifier> aggregateFields(final List<YangInstanceIdentifier> fields) {
+ return fields.stream()
+ .filter(field -> fields.stream()
+ .filter(fieldYiid -> !field.equals(fieldYiid))
+ .noneMatch(fieldYiid -> fieldYiid.contains(field)))
+ .collect(Collectors.toList());
+ }
+
+ /**
+ * Construct a tree based on the parent {@link YangInstanceIdentifier} and provided list of fields. The goal of this
+ * procedure is the elimination of the redundancy that is introduced by potentially overlapping parts of the fields
+ * paths.
+ *
+ * @param query path to parent element
+ * @param fields subpaths relative to parent path that identify specific fields
+ * @return created {@link PathNode} structure
+ */
+ private static PathNode constructPathArgumentTree(final YangInstanceIdentifier query,
+ final List<YangInstanceIdentifier> fields) {
+ final Iterator<PathArgument> queryIterator = query.getPathArguments().iterator();
+ final PathNode rootTreeNode = new PathNode(queryIterator.next());
+
+ PathNode queryTreeNode = rootTreeNode;
+ while (queryIterator.hasNext()) {
+ queryTreeNode = queryTreeNode.ensureChild(queryIterator.next());
+ }
+
+ for (final YangInstanceIdentifier field : fields) {
+ PathNode actualFieldTreeNode = queryTreeNode;
+ for (final PathArgument fieldPathArg : field.getPathArguments()) {
+ actualFieldTreeNode = actualFieldTreeNode.ensureChild(fieldPathArg);
+ }
+ }
+ return rootTreeNode;
+ }
+
+ public static NormalizedNodeResult transformDOMSourceToNormalizedNode(final MountPointContext mount,