/*
* Copyright (c) 2014 Cisco Systems, Inc. and others. All rights reserved.
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v1.0 which accompanies this distribution,
* and is available at http://www.eclipse.org/legal/epl-v10.html
*/
package org.opendaylight.yangtools.yang.data.api;
import com.google.common.base.Optional;
import com.google.common.base.Preconditions;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.common.collect.Lists;
import java.io.Serializable;
import java.lang.reflect.Array;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Collections;
import java.util.Iterator;
import java.util.List;
import java.util.Map;
import java.util.Map.Entry;
import java.util.Objects;
import java.util.Set;
import org.opendaylight.yangtools.concepts.Builder;
import org.opendaylight.yangtools.concepts.Immutable;
import org.opendaylight.yangtools.concepts.Path;
import org.opendaylight.yangtools.util.HashCodeBuilder;
import org.opendaylight.yangtools.yang.common.QName;
import org.opendaylight.yangtools.yang.data.api.schema.LeafSetEntryNode;
/**
* Unique identifier of a partical node instance in the data tree.
*
*
* Java representation of YANG Built-in type instance-identifier
,
* which conceptually is XPath expression minimised to uniquely identify element
* in data tree which conforms to constraints maintained by YANG Model,
* effectively this makes Instance Identifier a path to element in data tree.
*
* Constraints put in YANG specification on instance-identifier allowed it to be
* effectively represented in Java and it's evaluation does not require
* full-blown XPath processor.
*
*
Path Arguments
* Path to the node represented in instance identifier consists of
* {@link PathArgument} which carries necessary information to uniquely identify
* node on particular level in the subtree.
*
*
* - {@link NodeIdentifier} - Identifier of node, which has cardinality
*
0..1
in particular subtree in data tree.
* - {@link NodeIdentifierWithPredicates} - Identifier of node (list item),
* which has cardinality
0..n
.
* - {@link NodeWithValue} - Identifier of instance
leaf
node or
* leaf-list
node.
* - {@link AugmentationIdentifier} - Identifier of instance of
*
augmentation
node.
*
*
*
* @see http://tools.ietf.org/html/rfc6020#section-9.13
*/
public final class YangInstanceIdentifier implements Path, Immutable, Serializable {
private static final YangInstanceIdentifier EMPTY = trustedCreate(Collections.emptyList());
private static final long serialVersionUID = 2L;
private final Iterable pathArguments;
private final int hash;
private transient ImmutableList legacyPath = null;
private transient String toStringCache = null;
private final ImmutableList getLegacyPath() {
if (legacyPath == null) {
synchronized (this) {
if (legacyPath == null) {
legacyPath = ImmutableList.copyOf(pathArguments);
}
}
}
return legacyPath;
}
/**
* Returns a list of path arguments.
*
* @deprecated Use {@link #getPathArguments()} instead.
* @return Immutable list of path arguments.
*/
@Deprecated
public List getPath() {
return getLegacyPath();
}
/**
* Returns an ordered iteration of path arguments.
*
* @return Immutable iteration of path arguments.
*/
public Iterable getPathArguments() {
return pathArguments;
}
/**
* Returns an iterable of path arguments in reverse order. This is useful
* when walking up a tree organized this way.
*
* @return Immutable iterable of path arguments in reverse order.
*/
public Iterable getReversePathArguments() {
return getLegacyPath().reverse();
}
/**
* Returns the last PathArgument. This is equivalent of iterating
* to the last element of the iterable returned by {@link #getPathArguments()}.
*
* @return The last past argument, or null if there are no PathArguments.
*/
public PathArgument getLastPathArgument() {
return Iterables.getFirst(getReversePathArguments(), null);
}
private YangInstanceIdentifier(final Iterable path, final int hash) {
this.pathArguments = Preconditions.checkNotNull(path, "path must not be null.");
this.hash = hash;
}
private static final YangInstanceIdentifier trustedCreate(final Iterable path) {
final HashCodeBuilder hash = new HashCodeBuilder<>();
for (PathArgument a : path) {
hash.addArgument(a);
}
return new YangInstanceIdentifier(path, hash.toInstance());
}
public static final YangInstanceIdentifier create(final Iterable extends PathArgument> path) {
if (Iterables.isEmpty(path)) {
return EMPTY;
}
return trustedCreate(ImmutableList.copyOf(path));
}
public static final YangInstanceIdentifier create(final PathArgument... path) {
// We are forcing a copy, since we cannot trust the user
return create(Arrays.asList(path));
}
@Override
public int hashCode() {
/*
* The caching is safe, since the object contract requires
* immutability of the object and all objects referenced from this
* object.
* Used lists, maps are immutable. Path Arguments (elements) are also
* immutable, since the PathArgument contract requires immutability.
*/
return hash;
}
@Override
public boolean equals(final Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
YangInstanceIdentifier other = (YangInstanceIdentifier) obj;
if (this.hashCode() != obj.hashCode()) {
return false;
}
return Iterables.elementsEqual(pathArguments, other.pathArguments);
}
/**
* Constructs a new Instance Identifier with new {@link NodeIdentifier} added to the end of path arguments
*
* @param name QName of {@link NodeIdentifier}
* @return Instance Identifier with additional path argument added to the end.
*/
public YangInstanceIdentifier node(final QName name) {
return node(new NodeIdentifier(name));
}
/**
*
* Constructs a new Instance Identifier with new {@link PathArgument} added to the end of path arguments
*
* @param arg Path argument which should be added to the end
* @return Instance Identifier with additional path argument added to the end.
*/
public YangInstanceIdentifier node(final PathArgument arg) {
return new YangInstanceIdentifier(Iterables.concat(pathArguments, Collections.singleton(arg)), HashCodeBuilder.nextHashCode(hash, arg));
}
/**
* Get the relative path from an ancestor. This method attempts to perform
* the reverse of concatenating a base (ancestor) and a path.
*
* @param ancestor
* Ancestor against which the relative path should be calculated
* @return This object's relative path from parent, or Optional.absent() if
* the specified parent is not in fact an ancestor of this object.
*/
public Optional relativeTo(final YangInstanceIdentifier ancestor) {
final Iterator> lit = pathArguments.iterator();
final Iterator> oit = ancestor.pathArguments.iterator();
int common = 0;
while (oit.hasNext()) {
// Ancestor is not really an ancestor
if (!lit.hasNext() || !lit.next().equals(oit.next())) {
return Optional.absent();
}
++common;
}
if (common == 0) {
return Optional.of(this);
}
if (!lit.hasNext()) {
return Optional.of(EMPTY);
}
return Optional.of(trustedCreate(Iterables.skip(pathArguments, common)));
}
private static int hashCode(final Object value) {
if (value == null) {
return 0;
}
if (value.getClass().equals(byte[].class)) {
return Arrays.hashCode((byte[]) value);
}
if (value.getClass().isArray()) {
int hash = 0;
int length = Array.getLength(value);
for (int i = 0; i < length; i++) {
hash += Objects.hashCode(Array.get(value, i));
}
return hash;
}
return Objects.hashCode(value);
}
// Static factories & helpers
/**
*
* Returns a new InstanceIdentifier with only one path argument of type {@link NodeIdentifier} with supplied QName
*
* @param name QName of first node identifier
* @return Instance Identifier with only one path argument of type {@link NodeIdentifier}
*/
public static YangInstanceIdentifier of(final QName name) {
return create(new NodeIdentifier(name));
}
/**
*
* Returns new builder for InstanceIdentifier with empty path arguments.
*
* @return new builder for InstanceIdentifier with empty path arguments.
*/
static public InstanceIdentifierBuilder builder() {
return new BuilderImpl();
}
/**
*
* Returns new builder for InstanceIdentifier with path arguments copied from original instance identifier.
*
* @param origin Instace Identifier from which path arguments are copied.
* @return new builder for InstanceIdentifier with path arguments copied from original instance identifier.
*/
static public InstanceIdentifierBuilder builder(final YangInstanceIdentifier origin) {
return new BuilderImpl(origin.getPathArguments(), origin.hashCode());
}
/**
* Returns new builder for InstanceIdentifier with first path argument set to {@link NodeIdentifier}.
*
* @param node QName of first {@link NodeIdentifier} path argument.
* @return new builder for InstanceIdentifier with first path argument set to {@link NodeIdentifier}.
*
* @deprecated Either use {@link #node(QName)} or instantiate an intermediate builder.
*/
@Deprecated
public static InstanceIdentifierBuilder builder(final QName node) {
return builder().node(node);
}
/**
* Path argument / component of InstanceIdentifier
*
* Path argument uniquelly identifies node in data tree on particular
* level.
*
* This interface itself is used as common parent for actual
* path arguments types and should not be implemented by user code.
*
* Path arguments SHOULD contain only minimum of information
* required to uniquely identify node on particular subtree level.
*
* For actual path arguments types see:
*
* - {@link NodeIdentifier} - Identifier of container or leaf
*
- {@link NodeIdentifierWithPredicates} - Identifier of list entries, which have key defined
*
- {@link AugmentationIdentifier} - Identifier of augmentation
*
- {@link NodeWithValue} - Identifier of leaf-list entry
*
*/
public interface PathArgument extends Comparable, Immutable, Serializable {
/**
* If applicable returns unique QName of data node as defined in YANG
* Schema.
*
* This method may return null, if the corresponding schema node, does
* not have QName associated, such as in cases of augmentations.
*
* @return Node type
*/
QName getNodeType();
}
private static abstract class AbstractPathArgument implements PathArgument {
private static final long serialVersionUID = -4546547994250849340L;
private final QName nodeType;
protected AbstractPathArgument(final QName nodeType) {
this.nodeType = Preconditions.checkNotNull(nodeType);
}
@Override
public final QName getNodeType() {
return nodeType;
}
@Override
public int compareTo(final PathArgument o) {
return nodeType.compareTo(o.getNodeType());
}
@Override
public int hashCode() {
return 31 + getNodeType().hashCode();
}
@Override
public boolean equals(final Object obj) {
if (this == obj) {
return true;
}
if (obj == null || this.getClass() != obj.getClass()) {
return false;
}
return getNodeType().equals(((AbstractPathArgument)obj).getNodeType());
}
@Override
public String toString() {
return getNodeType().toString();
}
}
/**
*
* Fluent Builder of Instance Identifier instances
*
* @
*
*/
public interface InstanceIdentifierBuilder extends Builder {
/**
* Adds {@link NodeIdentifier} with supplied QName to path arguments of resulting instance identifier.
*
* @param nodeType QName of {@link NodeIdentifier} which will be added
* @return this builder
*/
InstanceIdentifierBuilder node(QName nodeType);
/**
* Adds {@link NodeIdentifierWithPredicates} with supplied QName and key values to path arguments of resulting instance identifier.
*
* @param nodeType QName of {@link NodeIdentifierWithPredicates} which will be added
* @param keyValues Map of key components and their respective values for {@link NodeIdentifierWithPredicates}
* @return this builder
*/
InstanceIdentifierBuilder nodeWithKey(QName nodeType, Map keyValues);
/**
* Adds {@link NodeIdentifierWithPredicates} with supplied QName and key, value.
*
* @param nodeType QName of {@link NodeIdentifierWithPredicates} which will be added
* @param key QName of key which will be added
* @param value value of key which will be added
* @return this builder
*/
InstanceIdentifierBuilder nodeWithKey(QName nodeType, QName key, Object value);
/**
*
* Builds an {@link YangInstanceIdentifier} with path arguments from this builder
*
* @return {@link YangInstanceIdentifier}
*/
YangInstanceIdentifier build();
}
/**
* Simple path argument identifying a {@link org.opendaylight.yangtools.yang.data.api.schema.ContainerNode} or
* {@link org.opendaylight.yangtools.yang.data.api.schema.LeafNode} leaf in particular subtree.
*/
public static final class NodeIdentifier extends AbstractPathArgument {
private static final long serialVersionUID = -2255888212390871347L;
public NodeIdentifier(final QName node) {
super(node);
}
}
/**
* Composite path argument identifying a {@link org.opendaylight.yangtools.yang.data.api.schema.MapEntryNode} leaf
* overall data tree.
*/
public static final class NodeIdentifierWithPredicates extends AbstractPathArgument {
private static final long serialVersionUID = -4787195606494761540L;
private final Map keyValues;
public NodeIdentifierWithPredicates(final QName node, final Map keyValues) {
super(node);
this.keyValues = ImmutableMap.copyOf(keyValues);
}
public NodeIdentifierWithPredicates(final QName node, final QName key, final Object value) {
this(node, ImmutableMap.of(key, value));
}
public Map getKeyValues() {
return keyValues;
}
@Override
public int hashCode() {
final int prime = 31;
int result = super.hashCode();
result = prime * result;
for (Entry entry : keyValues.entrySet()) {
result += Objects.hashCode(entry.getKey()) + YangInstanceIdentifier.hashCode(entry.getValue());
}
return result;
}
@Override
public boolean equals(final Object obj) {
if (!super.equals(obj)) {
return false;
}
final Map otherKeyValues = ((NodeIdentifierWithPredicates) obj).keyValues;
if (keyValues.size() != otherKeyValues.size()) {
return false;
}
for (Entry entry : keyValues.entrySet()) {
if (!otherKeyValues.containsKey(entry.getKey())
|| !Objects.deepEquals(entry.getValue(), otherKeyValues.get(entry.getKey()))) {
return false;
}
}
return true;
}
@Override
public String toString() {
return super.toString() + '[' + keyValues + ']';
}
}
/**
* Simple path argument identifying a {@link LeafSetEntryNode} leaf
* overall data tree.
*/
public static final class NodeWithValue extends AbstractPathArgument {
private static final long serialVersionUID = -3637456085341738431L;
private final Object value;
public NodeWithValue(final QName node, final Object value) {
super(node);
this.value = value;
}
public Object getValue() {
return value;
}
@Override
public int hashCode() {
final int prime = 31;
int result = super.hashCode();
result = prime * result + ((value == null) ? 0 : YangInstanceIdentifier.hashCode(value));
return result;
}
@Override
public boolean equals(final Object obj) {
if (!super.equals(obj)) {
return false;
}
final NodeWithValue other = (NodeWithValue) obj;
return Objects.deepEquals(value, other.value);
}
@Override
public String toString() {
return super.toString() + '[' + value + ']';
}
}
/**
* Composite path argument identifying a {@link org.opendaylight.yangtools.yang.data.api.schema.AugmentationNode} node in
* particular subtree.
*
* Augmentation is uniquely identified by set of all possible child nodes.
* This is possible
* to identify instance of augmentation,
* since RFC6020 states that augment
that augment
* statement must not add multiple nodes from same namespace
* / module to the target node.
*
*
* @see http://tools.ietf.org/html/rfc6020#section-7.15
*/
public static final class AugmentationIdentifier implements PathArgument {
private static final long serialVersionUID = -8122335594681936939L;
private final ImmutableSet childNames;
@Override
public QName getNodeType() {
// This should rather throw exception than return always null
throw new UnsupportedOperationException("Augmentation node has no QName");
}
/**
*
* Construct new augmentation identifier using supplied set of possible
* child nodes
*
* @param childNames
* Set of possible child nodes.
*/
public AugmentationIdentifier(final Set childNames) {
this.childNames = ImmutableSet.copyOf(childNames);
}
/**
* Augmentation node has no QName
*
* @deprecated Use
* {@link AugmentationIdentifier#AugmentationIdentifier(Set)}
* instead.
*/
@Deprecated
public AugmentationIdentifier(final QName nodeType, final Set childNames) {
this(childNames);
}
/**
*
* Returns set of all possible child nodes
*
* @return set of all possible child nodes.
*/
public Set getPossibleChildNames() {
return childNames;
}
@Override
public String toString() {
final StringBuffer sb = new StringBuffer("AugmentationIdentifier{");
sb.append("childNames=").append(childNames).append('}');
return sb.toString();
}
@Override
public boolean equals(final Object o) {
if (this == o) {
return true;
}
if (!(o instanceof AugmentationIdentifier)) {
return false;
}
AugmentationIdentifier that = (AugmentationIdentifier) o;
return childNames.equals(that.childNames);
}
@Override
public int hashCode() {
return childNames.hashCode();
}
@Override
public int compareTo(final PathArgument o) {
if (!(o instanceof AugmentationIdentifier)) {
return -1;
}
AugmentationIdentifier other = (AugmentationIdentifier) o;
Set otherChildNames = other.getPossibleChildNames();
int thisSize = childNames.size();
int otherSize = otherChildNames.size();
if (thisSize == otherSize) {
Iterator otherIterator = otherChildNames.iterator();
for (QName name : childNames) {
int c = name.compareTo(otherIterator.next());
if (c != 0) {
return c;
}
}
return 0;
} else if (thisSize < otherSize) {
return 1;
} else {
return -1;
}
}
}
private static class BuilderImpl implements InstanceIdentifierBuilder {
private final HashCodeBuilder hash;
private final List path;
public BuilderImpl() {
this.hash = new HashCodeBuilder<>();
this.path = new ArrayList<>();
}
public BuilderImpl(final Iterable prefix, final int hash) {
this.path = Lists.newArrayList(prefix);
this.hash = new HashCodeBuilder<>(hash);
}
@Override
public InstanceIdentifierBuilder node(final QName nodeType) {
final PathArgument arg = new NodeIdentifier(nodeType);
path.add(arg);
hash.addArgument(arg);
return this;
}
@Override
public InstanceIdentifierBuilder nodeWithKey(final QName nodeType, final QName key, final Object value) {
final PathArgument arg = new NodeIdentifierWithPredicates(nodeType, key, value);
path.add(arg);
hash.addArgument(arg);
return this;
}
@Override
public InstanceIdentifierBuilder nodeWithKey(final QName nodeType, final Map keyValues) {
final PathArgument arg = new NodeIdentifierWithPredicates(nodeType, keyValues);
path.add(arg);
hash.addArgument(arg);
return this;
}
@Override
@Deprecated
public YangInstanceIdentifier toInstance() {
return build();
}
@Override
public YangInstanceIdentifier build() {
return new YangInstanceIdentifier(ImmutableList.copyOf(path), hash.toInstance());
}
}
@Override
public boolean contains(final YangInstanceIdentifier other) {
Preconditions.checkArgument(other != null, "other should not be null");
final Iterator> lit = pathArguments.iterator();
final Iterator> oit = other.pathArguments.iterator();
while (lit.hasNext()) {
if (!oit.hasNext()) {
return false;
}
if (!lit.next().equals(oit.next())) {
return false;
}
}
return true;
}
@Override
public String toString() {
/*
* The toStringCache is safe, since the object contract requires
* immutability of the object and all objects referenced from this
* object.
* Used lists, maps are immutable. Path Arguments (elements) are also
* immutable, since the PathArgument contract requires immutability.
* The cache is thread-safe - if multiple computations occurs at the
* same time, cache will be overwritten with same result.
*/
if (toStringCache != null) {
return toStringCache;
}
final StringBuilder builder = new StringBuilder('/');
boolean first = true;
for (PathArgument argument : getPathArguments()) {
if (first) {
first = false;
} else {
builder.append('/');
}
builder.append(argument.toString());
}
toStringCache = builder.toString();
return toStringCache;
}
}