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