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.tree.DataTreeModification;
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.Version;
21 import org.opendaylight.yangtools.yang.data.impl.schema.NormalizedNodeUtils;
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 = TreeNodeUtils.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 NormalizedNodeUtils.findNode(key, data, path);
99 return Optional.absent();
103 private Optional<TreeNode> resolveSnapshot(final YangInstanceIdentifier path,
104 final ModifiedNode modification) {
105 final Optional<Optional<TreeNode>> potentialSnapshot = modification.getSnapshotCache();
106 if (potentialSnapshot.isPresent()) {
107 return potentialSnapshot.get();
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 ModificationApplyOperation resolveModificationStrategy(final YangInstanceIdentifier path) {
120 LOG.trace("Resolving modification apply strategy for {}", path);
121 if (rootNode.getType() == ModificationType.UNMODIFIED) {
122 strategyTree.upgradeIfPossible();
125 return TreeNodeUtils.<ModificationApplyOperation>findNodeChecked(strategyTree, path);
128 private OperationWithModification resolveModificationFor(final YangInstanceIdentifier path) {
129 // We ensure strategy is present.
130 final ModificationApplyOperation operation = resolveModificationStrategy(path);
132 final boolean isOrdered;
133 if (operation instanceof SchemaAwareApplyOperation) {
134 isOrdered = ((SchemaAwareApplyOperation) operation).isOrdered();
139 ModifiedNode modification = rootNode;
140 for (PathArgument pathArg : path.getPathArguments()) {
141 modification = modification.modifyChild(pathArg, isOrdered);
143 return OperationWithModification.from(operation, modification);
147 public void ready() {
148 final boolean wasRunning = UPDATER.compareAndSet(this, 0, 1);
149 Preconditions.checkState(wasRunning, "Attempted to seal an already-sealed Data Tree.");
154 private void checkSealed() {
155 Preconditions.checkState(sealed == 0, "Data Tree is sealed. No further modifications allowed.");
159 public String toString() {
160 return "MutableDataTree [modification=" + rootNode + "]";
164 public DataTreeModification newModification() {
165 Preconditions.checkState(sealed == 1, "Attempted to chain on an unsealed modification");
167 if (rootNode.getType() == ModificationType.UNMODIFIED) {
168 // Simple fast case: just use the underlying modification
169 return snapshot.newModification();
173 * We will use preallocated version, this means returned snapshot will
174 * have same version each time this method is called.
176 TreeNode originalSnapshotRoot = snapshot.getRootNode();
177 Optional<TreeNode> tempRoot = strategyTree.apply(rootNode, Optional.of(originalSnapshotRoot), version);
179 InMemoryDataTreeSnapshot tempTree = new InMemoryDataTreeSnapshot(snapshot.getSchemaContext(), tempRoot.get(), strategyTree);
180 return tempTree.newModification();
183 Version getVersion() {