2 * Copyright (c) 2015 Cisco Systems, Inc. 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.yangtools.yang.data.impl.schema.tree;
10 import java.util.Optional;
11 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
12 import org.opendaylight.yangtools.yang.data.api.schema.ContainerNode;
13 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
14 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNodeContainer;
15 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeConfiguration;
16 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
17 import org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType;
18 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.TreeNode;
19 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.TreeNodeFactory;
20 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.Version;
21 import org.opendaylight.yangtools.yang.data.impl.schema.ImmutableNodes;
22 import org.opendaylight.yangtools.yang.model.api.ContainerSchemaNode;
25 * Structural containers are special in that they appear when implied by child nodes and disappear whenever they are
26 * empty. We could implement this as a subclass of {@link SchemaAwareApplyOperation}, but the automatic semantic
27 * is quite different from all the other strategies. We create a {@link ContainerModificationStrategy} to tap into that
28 * logic, but wrap it so we only call out into it. We do not use {@link PresenceContainerModificationStrategy} because
29 * it enforces presence of mandatory leaves, which is not something we want here, as structural containers are not
30 * root anchors for that validation.
32 final class StructuralContainerModificationStrategy extends ModificationApplyOperation {
34 * Fake TreeNode version used in
35 * {@link #checkApplicable(ModificationPath, NodeModification, Optional, Version)}.
36 * It is okay to use a global constant, as the delegate will ignore it anyway. For
37 * {@link #apply(ModifiedNode, Optional, Version)} we will use the appropriate version as provided to us.
39 private static final Version FAKE_VERSION = Version.initial();
40 private final ContainerModificationStrategy delegate;
42 StructuralContainerModificationStrategy(final ContainerSchemaNode schemaNode,
43 final DataTreeConfiguration treeConfig) {
44 this.delegate = new ContainerModificationStrategy(schemaNode, treeConfig);
47 private Optional<TreeNode> fakeMeta(final Version version) {
48 final ContainerNode container = ImmutableNodes.containerNode(delegate.getSchema().getQName());
49 return Optional.of(TreeNodeFactory.createTreeNode(container, version));
53 Optional<TreeNode> apply(final ModifiedNode modification, final Optional<TreeNode> storeMeta,
54 final Version version) {
55 final Optional<TreeNode> ret;
56 if (modification.getOperation() == LogicalOperation.TOUCH && !storeMeta.isPresent()) {
57 // Container is not present, let's take care of the 'magically appear' part of our job
58 ret = delegate.apply(modification, fakeMeta(version), version);
60 // Fake container got removed: that is a no-op
61 if (!ret.isPresent()) {
62 modification.resolveModificationType(ModificationType.UNMODIFIED);
66 // If the delegate indicated SUBTREE_MODIFIED, account for the fake and report APPEARED
67 if (modification.getModificationType() == ModificationType.SUBTREE_MODIFIED) {
68 modification.resolveModificationType(ModificationType.APPEARED);
71 // Container is present, run normal apply operation
72 ret = delegate.apply(modification, storeMeta, version);
74 // Container was explicitly deleted, no magic required
75 if (!ret.isPresent()) {
81 * At this point ret is guaranteed to be present. We need to take care of the 'magically disappear' part of
82 * our job. Check if there are any child nodes left. If there are none, remove this container and turn the
83 * modification into a DISAPPEARED.
85 if (((NormalizedNodeContainer<?, ?, ?>) ret.get().getData()).getValue().isEmpty()) {
86 modification.resolveModificationType(ModificationType.DISAPPEARED);
87 return Optional.empty();
94 void checkApplicable(final ModificationPath path, final NodeModification modification,
95 final Optional<TreeNode> current, final Version version) throws DataValidationFailedException {
96 if (modification.getOperation() == LogicalOperation.TOUCH && !current.isPresent()) {
97 // Structural containers are created as needed, so we pretend this container is here
98 delegate.checkApplicable(path, modification, fakeMeta(FAKE_VERSION), version);
100 delegate.checkApplicable(path, modification, current, version);
105 void verifyStructure(final NormalizedNode<?, ?> modification, final boolean verifyChildren) {
106 delegate.verifyStructure(modification, verifyChildren);
110 void recursivelyVerifyStructure(final NormalizedNode<?, ?> value) {
111 delegate.recursivelyVerifyStructure(value);
115 ChildTrackingPolicy getChildPolicy() {
116 return delegate.getChildPolicy();
120 void mergeIntoModifiedNode(final ModifiedNode modification, final NormalizedNode<?, ?> value,
121 final Version version) {
122 delegate.mergeIntoModifiedNode(modification, value, version);
126 public Optional<ModificationApplyOperation> getChild(final PathArgument child) {
127 return delegate.getChild(child);