2 * Copyright (c) 2020 PANTHEON.tech, s.r.o. and others. All rights reserved.
4 * This program and the accompanying materials are made available under the
5 * terms of the Eclipse Public License v1.0 which accompanies this distribution,
6 * and is available at http://www.eclipse.org/legal/epl-v10.html
8 package org.opendaylight.mdsal.dom.spi.query;
10 import static com.google.common.base.Preconditions.checkArgument;
12 import java.util.AbstractMap.SimpleImmutableEntry;
13 import java.util.ArrayDeque;
14 import java.util.ArrayList;
15 import java.util.List;
16 import java.util.Map.Entry;
17 import java.util.Optional;
18 import org.eclipse.jdt.annotation.NonNullByDefault;
19 import org.opendaylight.mdsal.dom.api.query.DOMQuery;
20 import org.opendaylight.mdsal.dom.api.query.DOMQueryPredicate;
21 import org.opendaylight.mdsal.dom.api.query.DOMQueryResult;
22 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
23 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
24 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
25 import org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode;
26 import org.opendaylight.yangtools.yang.data.api.schema.MapNode;
27 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
28 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNodes;
31 public final class DOMQueryEvaluator {
32 private DOMQueryEvaluator() {
37 * Evaluate {@link DOMQuery} on its data element. The element is expected to correspond to
38 * {@link DOMQuery#getRoot()}.
40 * @param query Query to execute
41 * @param queryRoot Query root object
42 * @return Result of evaluation
43 * @throws NullPointerException if any argument is null
45 public static DOMQueryResult evaluateOn(final DOMQuery query, final NormalizedNode<?, ?> queryRoot) {
46 final YangInstanceIdentifier path = query.getSelect();
47 return path.isEmpty() ? evalSingle(queryRoot, query)
48 : evalPath(new ArrayDeque<>(path.getPathArguments()), queryRoot, query);
52 * Evaluate {@link DOMQuery} on a conceptual root. The element is expected to correspond to the conceptual data tree
53 * root. This method will first find the {@link DOMQuery#getRoot()} and then defer to
54 * {@link #evaluateOn(DOMQuery, NormalizedNode)}.
56 * @param query Query to execute
57 * @param root Conceptual root object
58 * @return Result of evaluation
59 * @throws NullPointerException if any argument is null
61 public static DOMQueryResult evaluateOnRoot(final DOMQuery query, final NormalizedNode<?, ?> root) {
62 NormalizedNode<?, ?> evalRoot = root;
63 for (PathArgument arg : query.getRoot().getPathArguments()) {
64 final Optional<NormalizedNode<?, ?>> next = NormalizedNodes.findNode(root, arg);
66 return DOMQueryResult.of();
68 evalRoot = next.orElseThrow();
70 return evaluateOn(query, evalRoot);
73 private static DOMQueryResult evalPath(final ArrayDeque<PathArgument> remaining, final NormalizedNode<?, ?> data,
74 final DOMQuery query) {
75 final List<Entry<YangInstanceIdentifier, NormalizedNode<?, ?>>> result = new ArrayList<>();
76 evalPath(result, query.getRoot(), remaining, data, query);
77 return DOMQueryResult.of(result);
80 private static void evalPath(final List<Entry<YangInstanceIdentifier, NormalizedNode<?,?>>> result,
81 final YangInstanceIdentifier path, final ArrayDeque<PathArgument> remaining,
82 final NormalizedNode<?, ?> data, final DOMQuery query) {
83 final PathArgument next = remaining.poll();
85 if (matches(data, query)) {
86 result.add(new SimpleImmutableEntry<>(path, data));
91 if (data instanceof MapNode && next instanceof NodeIdentifier) {
92 checkArgument(data.getIdentifier().equals(next), "Unexpected step %s", next);
93 for (MapEntryNode child : ((MapNode) data).getValue()) {
94 evalPath(result, path.node(child.getIdentifier()), remaining, child, query);
97 NormalizedNodes.getDirectChild(data, next).ifPresent(
98 child -> evalPath(result, path.node(next), remaining, child, query));
100 remaining.push(next);
103 private static DOMQueryResult evalSingle(final NormalizedNode<?, ?> data, final DOMQuery query) {
104 return matches(data, query) ? DOMQueryResult.of()
105 : DOMQueryResult.of(List.of(new SimpleImmutableEntry<>(query.getRoot(), data)));
108 private static boolean matches(final NormalizedNode<?, ?> data, final DOMQuery query) {
109 for (DOMQueryPredicate pred : query.getPredicates()) {
110 if (!pred.test(NormalizedNodes.findNode(data, pred.getPath()).orElse(null))) {