2 * Copyright (c) 2015 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.api;
10 import static com.google.common.base.Preconditions.checkArgument;
11 import static com.google.common.base.Verify.verify;
12 import static java.util.Objects.requireNonNull;
14 import com.google.common.collect.Iterables;
15 import com.google.common.collect.Lists;
16 import java.io.IOException;
17 import java.io.ObjectInputStream;
18 import java.io.ObjectOutputStream;
19 import java.lang.reflect.Field;
20 import java.util.ArrayList;
21 import java.util.List;
22 import javax.annotation.Nonnull;
24 final class StackedYangInstanceIdentifier extends YangInstanceIdentifier implements Cloneable {
25 private static final long serialVersionUID = 1L;
26 private static final Field PARENT_FIELD;
31 f = StackedYangInstanceIdentifier.class.getDeclaredField("parent");
32 } catch (NoSuchFieldException | SecurityException e) {
33 throw new ExceptionInInitializerError(e);
35 f.setAccessible(true);
40 private final YangInstanceIdentifier parent;
41 private final PathArgument pathArgument;
43 private transient volatile StackedPathArguments pathArguments;
44 private transient volatile StackedReversePathArguments reversePathArguments;
46 StackedYangInstanceIdentifier(final YangInstanceIdentifier parent, final PathArgument pathArgument,
49 this.parent = requireNonNull(parent);
50 this.pathArgument = requireNonNull(pathArgument);
54 public StackedYangInstanceIdentifier clone() {
56 return (StackedYangInstanceIdentifier) super.clone();
57 } catch (CloneNotSupportedException e) {
58 throw new IllegalStateException("clone() should be supported", e);
63 public YangInstanceIdentifier getParent() {
69 public YangInstanceIdentifier getAncestor(final int depth) {
70 checkArgument(depth >= 0, "Steps cannot be negative");
72 // Calculate how far up our FixedYangInstanceIdentifier ancestor is
74 YangInstanceIdentifier wlk = getParent();
75 while (wlk instanceof StackedYangInstanceIdentifier) {
76 wlk = wlk.getParent();
80 // Guaranteed to come from FixedYangInstanceIdentifier
81 final int fixedDepth = wlk.getPathArguments().size();
82 if (fixedDepth >= depth) {
83 return wlk.getAncestor(depth);
86 // Calculate our depth and check argument
87 final int ourDepth = stackedDepth + fixedDepth;
88 checkArgument(depth <= ourDepth, "Depth %s exceeds maximum depth %s", depth, ourDepth);
90 // Requested depth is covered by the stack, traverse up for specified number of steps
91 final int toWalk = ourDepth - depth;
92 YangInstanceIdentifier result = this;
93 for (int i = 0; i < toWalk; ++i) {
94 result = result.getParent();
101 public boolean isEmpty() {
106 public List<PathArgument> getPathArguments() {
107 StackedPathArguments ret = tryPathArguments();
109 final List<PathArgument> stack = new ArrayList<>();
110 YangInstanceIdentifier current = this;
112 verify(current instanceof StackedYangInstanceIdentifier);
113 final StackedYangInstanceIdentifier stacked = (StackedYangInstanceIdentifier) current;
114 stack.add(stacked.getLastPathArgument());
115 current = stacked.getParent();
116 } while (current.tryPathArguments() == null);
118 ret = new StackedPathArguments(current, Lists.reverse(stack));
126 public List<PathArgument> getReversePathArguments() {
127 StackedReversePathArguments ret = tryReversePathArguments();
129 ret = new StackedReversePathArguments(this);
130 reversePathArguments = ret;
136 public PathArgument getLastPathArgument() {
142 StackedPathArguments tryPathArguments() {
143 return pathArguments;
148 StackedReversePathArguments tryReversePathArguments() {
149 return reversePathArguments;
154 YangInstanceIdentifier createRelativeIdentifier(final int skipFromRoot) {
155 // TODO: can we optimize this one?
156 return YangInstanceIdentifier.create(Iterables.skip(getPathArguments(), skipFromRoot));
160 boolean pathArgumentsEqual(final YangInstanceIdentifier other) {
161 if (other instanceof StackedYangInstanceIdentifier) {
162 final StackedYangInstanceIdentifier stacked = (StackedYangInstanceIdentifier) other;
163 return pathArgument.equals(stacked.pathArgument) && parent.equals(stacked.parent);
165 return super.pathArgumentsEqual(other);
168 private void readObject(final ObjectInputStream inputStream) throws IOException, ClassNotFoundException {
169 inputStream.defaultReadObject();
171 final FixedYangInstanceIdentifier p = (FixedYangInstanceIdentifier) inputStream.readObject();
173 PARENT_FIELD.set(this, p);
174 } catch (IllegalArgumentException | IllegalAccessException e) {
175 throw new IOException("Failed to set parent", e);
179 private void writeObject(final ObjectOutputStream outputStream) throws IOException {
180 outputStream.defaultWriteObject();
182 final FixedYangInstanceIdentifier p;
183 if (parent instanceof FixedYangInstanceIdentifier) {
184 p = (FixedYangInstanceIdentifier) parent;
186 p = FixedYangInstanceIdentifier.create(parent.getPathArguments(), parent.hashCode());
188 outputStream.writeObject(p);
192 public YangInstanceIdentifier toOptimized() {
193 return FixedYangInstanceIdentifier.create(getPathArguments());