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 com.google.common.base.Preconditions;
11 import com.google.common.base.Verify;
12 import com.google.common.collect.Iterables;
13 import com.google.common.collect.Lists;
14 import java.io.IOException;
15 import java.io.ObjectInputStream;
16 import java.io.ObjectOutputStream;
17 import java.lang.reflect.Field;
18 import java.util.ArrayList;
19 import java.util.List;
21 final class StackedYangInstanceIdentifier extends YangInstanceIdentifier implements Cloneable {
22 private static final long serialVersionUID = 1L;
23 private static final Field PARENT_FIELD;
28 f = StackedYangInstanceIdentifier.class.getDeclaredField("parent");
29 } catch (NoSuchFieldException | SecurityException e) {
30 throw new ExceptionInInitializerError(e);
32 f.setAccessible(true);
37 private final YangInstanceIdentifier parent;
38 private final PathArgument pathArgument;
40 private transient volatile StackedPathArguments pathArguments;
41 private transient volatile StackedReversePathArguments reversePathArguments;
43 StackedYangInstanceIdentifier(final YangInstanceIdentifier parent, final PathArgument pathArgument, final int hash) {
45 this.parent = Preconditions.checkNotNull(parent);
46 this.pathArgument = Preconditions.checkNotNull(pathArgument);
50 public StackedYangInstanceIdentifier clone() {
52 return (StackedYangInstanceIdentifier) super.clone();
53 } catch (CloneNotSupportedException e) {
54 throw new IllegalStateException("clone() should be supported", e);
59 public YangInstanceIdentifier getParent() {
64 public YangInstanceIdentifier getAncestor(final int depth) {
65 Preconditions.checkArgument(depth >= 0, "Steps cannot be negative");
67 // Calculate how far up our FixedYangInstanceIdentifier ancestor is
69 YangInstanceIdentifier wlk = getParent();
70 while (wlk instanceof StackedYangInstanceIdentifier) {
71 wlk = wlk.getParent();
75 // Guaranteed to come from FixedYangInstanceIdentifier
76 final int fixedDepth = wlk.getPathArguments().size();
77 if (fixedDepth >= depth) {
78 return wlk.getAncestor(depth);
81 // Calculate our depth and check argument
82 final int ourDepth = stackedDepth + fixedDepth;
83 Preconditions.checkArgument(depth <= ourDepth, "Depth %s exceeds maximum depth %s", depth, ourDepth);
85 // Requested depth is covered by the stack, traverse up for specified number of steps
86 final int toWalk = ourDepth - depth;
87 YangInstanceIdentifier result = this;
88 for (int i = 0; i < toWalk; ++i) {
89 result = result.getParent();
96 public boolean isEmpty() {
101 public List<PathArgument> getPathArguments() {
102 StackedPathArguments ret = tryPathArguments();
104 final List<PathArgument> stack = new ArrayList<>();
105 YangInstanceIdentifier current = this;
107 Verify.verify(current instanceof StackedYangInstanceIdentifier);
108 final StackedYangInstanceIdentifier stacked = (StackedYangInstanceIdentifier) current;
109 stack.add(stacked.getLastPathArgument());
110 current = stacked.getParent();
111 } while (current.tryPathArguments() == null);
113 ret = new StackedPathArguments(current, Lists.reverse(stack));
121 public List<PathArgument> getReversePathArguments() {
122 StackedReversePathArguments ret = tryReversePathArguments();
124 ret = new StackedReversePathArguments(this);
125 reversePathArguments = ret;
131 public PathArgument getLastPathArgument() {
136 StackedPathArguments tryPathArguments() {
137 return pathArguments;
141 StackedReversePathArguments tryReversePathArguments() {
142 return reversePathArguments;
146 YangInstanceIdentifier createRelativeIdentifier(final int skipFromRoot) {
147 // TODO: can we optimize this one?
148 return YangInstanceIdentifier.create(Iterables.skip(getPathArguments(), skipFromRoot));
152 boolean pathArgumentsEqual(final YangInstanceIdentifier other) {
153 if (other instanceof StackedYangInstanceIdentifier) {
154 final StackedYangInstanceIdentifier stacked = (StackedYangInstanceIdentifier) other;
155 return pathArgument.equals(stacked.pathArgument) && parent.equals(stacked.parent);
157 return super.pathArgumentsEqual(other);
161 private void readObject(final ObjectInputStream inputStream) throws IOException, ClassNotFoundException {
162 inputStream.defaultReadObject();
164 final FixedYangInstanceIdentifier p = (FixedYangInstanceIdentifier) inputStream.readObject();
166 PARENT_FIELD.set(this, p);
167 } catch (IllegalArgumentException | IllegalAccessException e) {
168 throw new IOException("Failed to set parent", e);
172 private void writeObject(final ObjectOutputStream outputStream) throws IOException {
173 outputStream.defaultWriteObject();
175 final FixedYangInstanceIdentifier p;
176 if (parent instanceof FixedYangInstanceIdentifier) {
177 p = (FixedYangInstanceIdentifier) parent;
179 p = FixedYangInstanceIdentifier.create(parent.getPathArguments(), parent.hashCode());
181 outputStream.writeObject(p);
185 public YangInstanceIdentifier toOptimized() {
186 return FixedYangInstanceIdentifier.create(getPathArguments());