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;
12 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
13 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
14 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataValidationFailedException;
15 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.TreeNode;
16 import org.opendaylight.yangtools.yang.data.api.schema.tree.spi.Version;
19 * Represents a {@link ModificationApplyOperation} which is rooted at conceptual
23 * This implementation differs from other implementations in this package that
24 * is not immutable, but may be upgraded to newer state if available by
25 * explicitly invoking {@link #upgradeIfPossible()} and also serves as factory
26 * for deriving snapshot {@link RootModificationApplyOperation} which will not
27 * be affected by upgrade of original one.
30 * There are two variations of this {@link ModificationApplyOperation}:
33 * <b>Upgradable</b> - operation may be upgraded to different backing
34 * implementation by invoking {@link #upgradeIfPossible()}.</li>
35 * <li><b>Not Upgradable</b> - operation is immutable, invocation of
36 * {@link #upgradeIfPossible()} is no-op and method {@link #snapshot()} returns
37 * pointer on same object.
39 * <h3>Upgradable Root Modification Operation</h3>
41 * Upgradable Root Modification Operation may be created using:
43 * <li> {@link #from(ModificationApplyOperation)} with other upgradable root
44 * modification as an argument
45 * <li>using factory {@link LatestOperationHolder} which instantiates Upgradable
46 * Root Modification Operations and provides an option to set latest
50 * Upgradable root operation is never upgraded to latest operation
51 * automatically, but client code must explicitly invoke
52 * {@link #upgradeIfPossible()} to get latest implementation.
54 * Note: This is helpful for implementing
55 * {@link org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeModification}
56 * which may be derived from
57 * {@link org.opendaylight.yangtools.yang.data.api.schema.tree.DataTree} before
58 * update of schema and user actually writes data after schema update. During
59 * update user did not invoked any operation.
62 abstract class RootModificationApplyOperation implements ModificationApplyOperation {
65 public Optional<ModificationApplyOperation> getChild(final PathArgument child) {
66 return getDelegate().getChild(child);
70 public final void checkApplicable(final YangInstanceIdentifier path, final NodeModification modification, final Optional<TreeNode> current)
71 throws DataValidationFailedException {
72 getDelegate().checkApplicable(path, modification, current);
76 public final Optional<TreeNode> apply(final ModifiedNode modification, final Optional<TreeNode> currentMeta,
77 final Version version) {
78 return getDelegate().apply(modification, currentMeta, version);
82 public boolean equals(final Object obj) {
83 return getDelegate().equals(obj);
87 public int hashCode() {
88 return getDelegate().hashCode();
92 public String toString() {
93 return getDelegate().toString();
97 public void verifyStructure(final ModifiedNode modification) throws IllegalArgumentException {
98 getDelegate().verifyStructure(modification);
102 * Return the underlying delegate.
104 * @return Underlying delegate.
106 abstract ModificationApplyOperation getDelegate();
109 * Creates a snapshot from this modification, which may have separate
110 * upgrade lifecycle and is not affected by upgrades
112 * Newly created snapshot uses backing implementation of this modi
114 * @return Derived {@link RootModificationApplyOperation} with separate
117 public abstract RootModificationApplyOperation snapshot();
120 * Upgrades backing implementation to latest available, if possible.
122 * Latest implementation of {@link RootModificationApplyOperation} is
123 * managed by {@link LatestOperationHolder} which was used to construct this
124 * operation and latest operation is updated by
125 * {@link LatestOperationHolder#setCurrent(ModificationApplyOperation)}.
127 public abstract void upgradeIfPossible();
129 public static RootModificationApplyOperation from(final ModificationApplyOperation resolver) {
130 if (resolver instanceof RootModificationApplyOperation) {
131 return ((RootModificationApplyOperation) resolver).snapshot();
133 return new NotUpgradableModificationApplyOperation(resolver);