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 java.util.Map.Entry;
13 import java.util.concurrent.atomic.AtomicIntegerFieldUpdater;
14 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
15 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
16 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNode;
17 import org.opendaylight.yangtools.yang.data.api.schema.NormalizedNodes;
18 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification;
19 import org.opendaylight.yangtools.yang.data.api.schema.tree.StoreTreeNodes;
20 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.TreeNode;
21 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.Version;
22 import org.slf4j.Logger;
23 import org.slf4j.LoggerFactory;
25 final class InMemoryDataTreeModification implements DataTreeModification {
26 private static final AtomicIntegerFieldUpdater<InMemoryDataTreeModification> UPDATER =
27 AtomicIntegerFieldUpdater.newUpdater(InMemoryDataTreeModification.class, "sealed");
28 private static final Logger LOG = LoggerFactory.getLogger(InMemoryDataTreeModification.class);
30 private final RootModificationApplyOperation strategyTree;
31 private final InMemoryDataTreeSnapshot snapshot;
32 private final ModifiedNode rootNode;
33 private final Version version;
35 private volatile int sealed = 0;
37 InMemoryDataTreeModification(final InMemoryDataTreeSnapshot snapshot, final RootModificationApplyOperation resolver) {
38 this.snapshot = Preconditions.checkNotNull(snapshot);
39 this.strategyTree = Preconditions.checkNotNull(resolver).snapshot();
40 this.rootNode = ModifiedNode.createUnmodified(snapshot.getRootNode(), false);
43 * We could allocate version beforehand, since Version contract
44 * states two allocated version must be always different.
46 * Preallocating version simplifies scenarios such as
47 * chaining of modifications, since version for particular
48 * node in modification and in data tree (if successfully
49 * committed) will be same and will not change.
51 this.version = snapshot.getRootNode().getSubtreeVersion().next();
54 ModifiedNode getRootModification() {
58 ModificationApplyOperation getStrategy() {
63 public void write(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
66 resolveModificationFor(path).write(data);
70 public void merge(final YangInstanceIdentifier path, final NormalizedNode<?, ?> data) {
73 resolveModificationFor(path).merge(data);
77 public void delete(final YangInstanceIdentifier path) {
80 resolveModificationFor(path).delete();
84 public Optional<NormalizedNode<?, ?>> readNode(final YangInstanceIdentifier path) {
86 * Walk the tree from the top, looking for the first node between root and
87 * the requested path which has been modified. If no such node exists,
88 * we use the node itself.
90 final Entry<YangInstanceIdentifier, ModifiedNode> entry = StoreTreeNodes.findClosestsOrFirstMatch(rootNode, path, ModifiedNode.IS_TERMINAL_PREDICATE);
91 final YangInstanceIdentifier key = entry.getKey();
92 final ModifiedNode mod = entry.getValue();
94 final Optional<TreeNode> result = resolveSnapshot(key, mod);
95 if (result.isPresent()) {
96 NormalizedNode<?, ?> data = result.get().getData();
97 return NormalizedNodes.findNode(key, data, path);
99 return Optional.absent();
103 private Optional<TreeNode> resolveSnapshot(final YangInstanceIdentifier path, final ModifiedNode modification) {
104 final Optional<TreeNode> potentialSnapshot = modification.getSnapshot();
105 if (potentialSnapshot != null) {
106 return potentialSnapshot;
110 return resolveModificationStrategy(path).apply(modification, modification.getOriginal(),
112 } catch (Exception e) {
113 LOG.error("Could not create snapshot for {}:{}", path, modification, e);
118 private ModificationApplyOperation resolveModificationStrategy(final YangInstanceIdentifier path) {
119 LOG.trace("Resolving modification apply strategy for {}", path);
120 if (rootNode.getOperation() == LogicalOperation.NONE) {
121 strategyTree.upgradeIfPossible();
124 return StoreTreeNodes.<ModificationApplyOperation>findNodeChecked(strategyTree, path);
127 private OperationWithModification resolveModificationFor(final YangInstanceIdentifier path) {
128 // We ensure strategy is present.
129 final ModificationApplyOperation operation = resolveModificationStrategy(path);
131 final boolean isOrdered;
132 if (operation instanceof SchemaAwareApplyOperation) {
133 isOrdered = ((SchemaAwareApplyOperation) operation).isOrdered();
138 ModifiedNode modification = rootNode;
139 for (PathArgument pathArg : path.getPathArguments()) {
140 modification = modification.modifyChild(pathArg, isOrdered);
142 return OperationWithModification.from(operation, modification);
146 public void ready() {
147 final boolean wasRunning = UPDATER.compareAndSet(this, 0, 1);
148 Preconditions.checkState(wasRunning, "Attempted to seal an already-sealed Data Tree.");
153 private void checkSealed() {
154 Preconditions.checkState(sealed == 0, "Data Tree is sealed. No further modifications allowed.");
158 public String toString() {
159 return "MutableDataTree [modification=" + rootNode + "]";
163 public DataTreeModification newModification() {
164 Preconditions.checkState(sealed == 1, "Attempted to chain on an unsealed modification");
166 if (rootNode.getOperation() == LogicalOperation.NONE) {
167 // Simple fast case: just use the underlying modification
168 return snapshot.newModification();
172 * We will use preallocated version, this means returned snapshot will
173 * have same version each time this method is called.
175 TreeNode originalSnapshotRoot = snapshot.getRootNode();
176 Optional<TreeNode> tempRoot = strategyTree.apply(rootNode, Optional.of(originalSnapshotRoot), version);
178 InMemoryDataTreeSnapshot tempTree = new InMemoryDataTreeSnapshot(snapshot.getSchemaContext(), tempRoot.get(), strategyTree);
179 return tempTree.newModification();
182 Version getVersion() {