2 * Copyright (c) 2014 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 com.google.common.base.Preconditions;
12 import com.google.common.base.Predicate;
13 import com.google.common.base.Verify;
14 import java.util.Collection;
15 import java.util.HashMap;
16 import java.util.Iterator;
17 import java.util.LinkedHashMap;
19 import javax.annotation.Nonnull;
20 import javax.annotation.concurrent.NotThreadSafe;
21 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
22 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
23 import org.opendaylight.yangtools.yang.data.api.schema.tree.ModificationType;
24 import org.opendaylight.yangtools.yang.data.api.schema.tree.StoreTreeNode;
25 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.TreeNode;
28 * Node Modification Node and Tree
30 * Tree which structurally resembles data tree and captures client modifications
31 * to the data store tree.
33 * This tree is lazily created and populated via {@link #modifyChild(PathArgument)}
34 * and {@link TreeNode} which represents original state as tracked by {@link #getOriginal()}.
37 final class ModifiedNode extends NodeModification implements StoreTreeNode<ModifiedNode> {
38 static final Predicate<ModifiedNode> IS_TERMINAL_PREDICATE = new Predicate<ModifiedNode>() {
40 public boolean apply(final @Nonnull ModifiedNode input) {
41 Preconditions.checkNotNull(input);
42 switch (input.getOperation()) {
52 throw new IllegalArgumentException(String.format("Unhandled modification type %s", input.getOperation()));
56 private final Map<PathArgument, ModifiedNode> children;
57 private final Optional<TreeNode> original;
58 private final PathArgument identifier;
59 private LogicalOperation operation = LogicalOperation.NONE;
60 private Optional<TreeNode> snapshotCache;
61 private NormalizedNode<?, ?> value;
62 private ModificationType modType;
64 private ModifiedNode(final PathArgument identifier, final Optional<TreeNode> original, final boolean isOrdered) {
65 this.identifier = identifier;
66 this.original = original;
69 children = new LinkedHashMap<>();
71 children = new HashMap<>();
76 * Return the value which was written to this node.
78 * @return Currently-written value
80 public NormalizedNode<?, ?> getWrittenValue() {
85 public PathArgument getIdentifier() {
90 Optional<TreeNode> getOriginal() {
95 LogicalOperation getOperation() {
101 * Returns child modification if child was modified
103 * @return Child modification if direct child or it's subtree
108 public Optional<ModifiedNode> getChild(final PathArgument child) {
109 return Optional.<ModifiedNode> fromNullable(children.get(child));
114 * Returns child modification if child was modified, creates {@link ModifiedNode}
115 * for child otherwise.
117 * If this node's {@link ModificationType} is {@link ModificationType#UNMODIFIED}
118 * changes modification type to {@link ModificationType#SUBTREE_MODIFIED}
121 * @return {@link ModifiedNode} for specified child, with {@link #getOriginal()}
122 * containing child metadata if child was present in original data.
124 ModifiedNode modifyChild(final PathArgument child, final boolean isOrdered) {
126 if (operation == LogicalOperation.NONE) {
127 updateOperationType(LogicalOperation.TOUCH);
129 final ModifiedNode potential = children.get(child);
130 if (potential != null) {
134 final Optional<TreeNode> currentMetadata;
135 if (original.isPresent()) {
136 final TreeNode orig = original.get();
137 currentMetadata = orig.getChild(child);
139 currentMetadata = Optional.absent();
142 final ModifiedNode newlyCreated = new ModifiedNode(child, currentMetadata, isOrdered);
143 children.put(child, newlyCreated);
148 * Returns all recorded direct child modification
150 * @return all recorded direct child modifications
153 Collection<ModifiedNode> getChildren() {
154 return children.values();
158 * Records a delete for associated node.
161 final LogicalOperation newType;
166 // We need to record this delete.
167 newType = LogicalOperation.DELETE;
173 * We are canceling a previous modification. This is a bit tricky,
174 * as the original write may have just introduced the data, or it
175 * may have modified it.
177 * As documented in BUG-2470, a delete of data introduced in this
178 * transaction needs to be turned into a no-op.
180 newType = original.isPresent() ? LogicalOperation.DELETE : LogicalOperation.NONE;
183 throw new IllegalStateException("Unhandled deletion of node with " + operation);
189 updateOperationType(newType);
193 * Records a write for associated node.
197 void write(final NormalizedNode<?, ?> value) {
199 updateOperationType(LogicalOperation.WRITE);
204 void merge(final NormalizedNode<?, ?> value) {
206 updateOperationType(LogicalOperation.MERGE);
209 * Blind overwrite of any previous data is okay, no matter whether the node
210 * is simple or complex type.
212 * If this is a simple or complex type with unkeyed children, this merge will
213 * be turned into a write operation, overwriting whatever was there before.
215 * If this is a container with keyed children, there are two possibilities:
216 * - if it existed before, this value will never be consulted and the children
217 * will get explicitly merged onto the original data.
218 * - if it did not exist before, this value will be used as a seed write and
219 * children will be merged into it.
220 * In either case we rely on OperationWithModification to manipulate the children
221 * before calling this method, so unlike a write we do not want to clear them.
227 * Seal the modification node and prune any children which has not been
233 // Walk all child nodes and remove any children which have not
235 final Iterator<ModifiedNode> it = children.values().iterator();
236 while (it.hasNext()) {
237 final ModifiedNode child = it.next();
240 if (child.operation == LogicalOperation.NONE) {
245 // A TOUCH node without any children is a no-op
246 if (operation == LogicalOperation.TOUCH && children.isEmpty()) {
247 updateOperationType(LogicalOperation.NONE);
251 private void clearSnapshot() {
252 snapshotCache = null;
255 Optional<TreeNode> getSnapshot() {
256 return snapshotCache;
259 Optional<TreeNode> setSnapshot(final Optional<TreeNode> snapshot) {
260 snapshotCache = Preconditions.checkNotNull(snapshot);
264 private void updateOperationType(final LogicalOperation type) {
271 public String toString() {
272 return "NodeModification [identifier=" + identifier + ", modificationType="
273 + operation + ", childModification=" + children + "]";
276 void resolveModificationType(@Nonnull final ModificationType type) {
280 @Nonnull ModificationType modificationType() {
281 return Verify.verifyNotNull(modType, "Node %s does not have resolved modification type", this);
285 * Create a node which will reflect the state of this node, except it will behave as newly-written
286 * value. This is useful only for merge validation.
288 * @param value Value associated with the node
289 * @return An isolated node. This node should never reach a datatree.
291 ModifiedNode asNewlyWritten(final NormalizedNode<?, ?> value) {
292 final ModifiedNode ret = new ModifiedNode(getIdentifier(), Optional.<TreeNode>absent(), false);
297 public static ModifiedNode createUnmodified(final TreeNode metadataTree, final boolean isOrdered) {
298 return new ModifiedNode(metadataTree.getIdentifier(), Optional.of(metadataTree), isOrdered);