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.collect.Iterables;
13 import java.util.Map.Entry;
14 import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
15 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
16 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
17 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
18 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNodes;
19 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
20 import org.opendaylight.yangtools.yang.data.api.schema.tree.StoreTreeNodes;
21 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.TreeNode;
22 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.Version;
23 import org.slf4j.Logger;
24 import org.slf4j.LoggerFactory;
26 final class InMemoryDataTreeModification implements DataTreeModification {
27 private static final AtomicIntegerFieldUpdater<InMemoryDataTreeModification> UPDATER =
28 AtomicIntegerFieldUpdater.newUpdater(InMemoryDataTreeModification.class, "sealed");
29 private static final Logger LOG = LoggerFactory.getLogger(InMemoryDataTreeModification.class);
31 private final RootModificationApplyOperation strategyTree;
32 private final InMemoryDataTreeSnapshot snapshot;
33 private final ModifiedNode rootNode;
34 private final Version version;
36 private volatile int sealed = 0;
38 InMemoryDataTreeModification(final InMemoryDataTreeSnapshot snapshot, final RootModificationApplyOperation resolver) {
39 this.snapshot = Preconditions.checkNotNull(snapshot);
40 this.strategyTree = Preconditions.checkNotNull(resolver).snapshot();
41 this.rootNode = ModifiedNode.createUnmodified(snapshot.getRootNode(), strategyTree.getChildPolicy());
44 * We could allocate version beforehand, since Version contract
45 * states two allocated version must be always different.
47 * Preallocating version simplifies scenarios such as
48 * chaining of modifications, since version for particular
49 * node in modification and in data tree (if successfully
50 * committed) will be same and will not change.
52 this.version = snapshot.getRootNode().getSubtreeVersion().next();
55 ModifiedNode getRootModification() {
59 ModificationApplyOperation getStrategy() {
64 public void write(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
67 resolveModificationFor(path).write(data);
71 public void merge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
74 resolveModificationFor(path).merge(data);
78 public void delete(final YangInstanceIdentifier path) {
81 resolveModificationFor(path).delete();
85 public Optional<NormalizedNode<?, ?>> readNode(final YangInstanceIdentifier path) {
87 * Walk the tree from the top, looking for the first node between root and
88 * the requested path which has been modified. If no such node exists,
89 * we use the node itself.
91 final Entry<YangInstanceIdentifier, ModifiedNode> entry = StoreTreeNodes.findClosestsOrFirstMatch(rootNode, path, ModifiedNode.IS_TERMINAL_PREDICATE);
92 final YangInstanceIdentifier key = entry.getKey();
93 final ModifiedNode mod = entry.getValue();
95 final Optional<TreeNode> result = resolveSnapshot(key, mod);
96 if (result.isPresent()) {
97 NormalizedNode<?, ?> data = result.get().getData();
98 return NormalizedNodes.findNode(key, data, path);
100 return Optional.absent();
104 private Optional<TreeNode> resolveSnapshot(final YangInstanceIdentifier path, final ModifiedNode modification) {
105 final Optional<TreeNode> potentialSnapshot = modification.getSnapshot();
106 if (potentialSnapshot != null) {
107 return potentialSnapshot;
111 return resolveModificationStrategy(path).apply(modification, modification.getOriginal(),
113 } catch (Exception e) {
114 LOG.error("Could not create snapshot for {}:{}", path, modification, e);
119 private void upgradeIfPossible() {
120 if (rootNode.getOperation() == LogicalOperation.NONE) {
121 strategyTree.upgradeIfPossible();
125 private ModificationApplyOperation resolveModificationStrategy(final YangInstanceIdentifier path) {
126 LOG.trace("Resolving modification apply strategy for {}", path);
129 return StoreTreeNodes.<ModificationApplyOperation>findNodeChecked(strategyTree, path);
132 private OperationWithModification resolveModificationFor(final YangInstanceIdentifier path) {
136 * Walk the strategy and modification trees in-sync, creating modification nodes as needed.
138 * If the user has provided wrong input, we may end up with a bunch of TOUCH nodes present
139 * ending with an empty one, as we will throw the exception below. This fact could end up
140 * being a problem, as we'd have bunch of phantom operations.
142 * That is fine, as we will prune any empty TOUCH nodes in the last phase of the ready
145 ModificationApplyOperation operation = strategyTree;
146 ModifiedNode modification = rootNode;
149 for(PathArgument pathArg : path.getPathArguments()) {
150 Optional<ModificationApplyOperation> potential = operation.getChild(pathArg);
151 if (!potential.isPresent()) {
152 throw new IllegalArgumentException(String.format("Child %s is not present in schema tree.",
153 Iterables.toString(Iterables.limit(path.getPathArguments(), i))));
155 operation = potential.get();
158 modification = modification.modifyChild(pathArg, operation.getChildPolicy());
161 return OperationWithModification.from(operation, modification);
165 public void ready() {
166 final boolean wasRunning = UPDATER.compareAndSet(this, 0, 1);
167 Preconditions.checkState(wasRunning, "Attempted to seal an already-sealed Data Tree.");
172 private void checkSealed() {
173 Preconditions.checkState(sealed == 0, "Data Tree is sealed. No further modifications allowed.");
177 public String toString() {
178 return "MutableDataTree [modification=" + rootNode + "]";
182 public DataTreeModification newModification() {
183 Preconditions.checkState(sealed == 1, "Attempted to chain on an unsealed modification");
185 if (rootNode.getOperation() == LogicalOperation.NONE) {
186 // Simple fast case: just use the underlying modification
187 return snapshot.newModification();
191 * We will use preallocated version, this means returned snapshot will
192 * have same version each time this method is called.
194 TreeNode originalSnapshotRoot = snapshot.getRootNode();
195 Optional<TreeNode> tempRoot = strategyTree.apply(rootNode, Optional.of(originalSnapshotRoot), version);
197 InMemoryDataTreeSnapshot tempTree = new InMemoryDataTreeSnapshot(snapshot.getSchemaContext(), tempRoot.get(), strategyTree);
198 return tempTree.newModification();
201 Version getVersion() {