/*
* Copyright (c) 2013 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.model.api;
import static com.google.common.base.Preconditions.checkArgument;
import static com.google.common.base.Preconditions.checkState;
import static java.util.Objects.requireNonNull;
import com.google.common.base.MoreObjects;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.Iterables;
import com.google.common.collect.UnmodifiableIterator;
import java.util.Arrays;
import java.util.List;
import java.util.NoSuchElementException;
import java.util.Objects;
import org.eclipse.jdt.annotation.NonNull;
import org.opendaylight.yangtools.concepts.Immutable;
import org.opendaylight.yangtools.yang.common.QName;
import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier;
import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier.Absolute;
import org.opendaylight.yangtools.yang.model.api.stmt.SchemaNodeIdentifier.Descendant;
/**
* Represents unique path to the every node inside the module.
*
* @deprecated This path is not really unique, as it does not handle YANG namespace overlap correctly. There are two
* different replacements for this class:
*
* - {@link SchemaNodeIdentifier} for use in
* YANG schema addressing
* contexts
* - {@link EffectiveStatementInference} for use in contexts where the intent is to exchange pointer
* to a specific statement. Unlike SchemaPath, though, it does not require additional lookup in most
* cases
*
* This class is scheduled for removal in the next major release.
*/
@Deprecated(since = "7.0.8", forRemoval = true)
public abstract class SchemaPath implements Immutable {
/**
* An absolute SchemaPath.
*/
private static final class AbsoluteSchemaPath extends SchemaPath {
private AbsoluteSchemaPath(final SchemaPath parent, final QName qname) {
super(parent, qname);
}
@Override
public boolean isAbsolute() {
return true;
}
@Override
public AbsoluteSchemaPath createChild(final QName element) {
return new AbsoluteSchemaPath(this, requireNonNull(element));
}
}
/**
* A relative SchemaPath.
*/
private static final class RelativeSchemaPath extends SchemaPath {
private RelativeSchemaPath(final SchemaPath parent, final QName qname) {
super(parent, qname);
}
@Override
public boolean isAbsolute() {
return false;
}
@Override
public RelativeSchemaPath createChild(final QName element) {
return new RelativeSchemaPath(this, requireNonNull(element));
}
}
/**
* Shared instance of the conceptual root schema node.
*/
public static final @NonNull SchemaPath ROOT = new AbsoluteSchemaPath(null, null);
/**
* Shared instance of the "same" relative schema node.
*/
public static final @NonNull SchemaPath SAME = new RelativeSchemaPath(null, null);
/**
* Parent path.
*/
private final SchemaPath parent;
/**
* This component.
*/
private final QName qname;
/**
* Cached hash code. We can use this since we are immutable.
*/
private final int hash;
SchemaPath(final SchemaPath parent, final QName qname) {
this.parent = parent;
this.qname = qname;
int tmp = Objects.hashCode(parent);
if (qname != null) {
tmp = tmp * 31 + qname.hashCode();
}
hash = tmp;
}
public static @NonNull SchemaPath of(final SchemaNodeIdentifier path) {
if (path instanceof Absolute) {
return of((Absolute) path);
} else if (path instanceof Descendant) {
return of((Descendant) path);
} else {
throw new IllegalStateException("Unexpected path " + requireNonNull(path));
}
}
public static @NonNull SchemaPath of(final Absolute path) {
return SchemaPath.ROOT.createChild(path.getNodeIdentifiers());
}
public static @NonNull SchemaPath of(final Descendant path) {
return SchemaPath.SAME.createChild(path.getNodeIdentifiers());
}
/**
* Constructs new instance of this class with the concrete path.
*
* @param path
* list of QName instances which specifies exact path to the
* module node
* @param absolute
* boolean value which specifies if the path is absolute or
* relative
*
* @return A SchemaPath instance.
*/
public static @NonNull SchemaPath create(final Iterable path, final boolean absolute) {
return (absolute ? ROOT : SAME).createChild(path);
}
/**
* Constructs new instance of this class with the concrete path.
*
* @param absolute
* boolean value which specifies if the path is absolute or
* relative
* @param element
* a single QName which specifies exact path to the
* module node
*
* @return A SchemaPath instance.
*/
public static @NonNull SchemaPath create(final boolean absolute, final QName element) {
return (absolute ? ROOT : SAME).createChild(element);
}
/**
* Constructs new instance of this class with the concrete path.
*
* @param absolute
* boolean value which specifies if the path is absolute or
* relative
* @param path
* one or more QName instances which specifies exact path to the
* module node
*
* @return A SchemaPath instance.
*/
public static @NonNull SchemaPath create(final boolean absolute, final QName... path) {
return create(Arrays.asList(path), absolute);
}
/**
* Create a child path based on concatenation of this path and a relative path.
*
* @param relative Relative path
* @return A new child path
*/
public @NonNull SchemaPath createChild(final Iterable relative) {
if (Iterables.isEmpty(relative)) {
return this;
}
SchemaPath parentPath = this;
for (QName item : relative) {
parentPath = parentPath.createChild(item);
}
return parentPath;
}
/**
* Create a child path based on concatenation of this path and a relative path.
*
* @param relative Relative SchemaPath
* @return A new child path
*/
public @NonNull SchemaPath createChild(final SchemaPath relative) {
checkArgument(!relative.isAbsolute(), "Child creation requires relative path");
return createChild(relative.getPathFromRoot());
}
/**
* Create a child path based on concatenation of this path and an additional path element.
*
* @param element Relative SchemaPath elements
* @return A new child path
*/
public abstract @NonNull SchemaPath createChild(QName element);
/**
* Create a child path based on concatenation of this path and additional
* path elements.
*
* @param elements Relative SchemaPath elements
* @return A new child path
*/
public @NonNull SchemaPath createChild(final QName... elements) {
return createChild(Arrays.asList(elements));
}
/**
* Returns the list of nodes which need to be traversed to get from the
* starting point (root for absolute SchemaPaths) to the node represented
* by this object.
*
* @return list of qname
instances which represents
* path from the root to the schema node.
*/
public List getPathFromRoot() {
if (qname == null) {
return ImmutableList.of();
}
return parent == null ? ImmutableList.of(qname) : new PathFromRoot(this);
}
/**
* Returns the list of nodes which need to be traversed to get from this
* node to the starting point (root for absolute SchemaPaths).
*
* @return list of qname
instances which represents
* path from the schema node towards the root.
*/
public Iterable getPathTowardsRoot() {
return () -> new UnmodifiableIterator<>() {
private SchemaPath current = SchemaPath.this;
@Override
public boolean hasNext() {
return current.parent != null;
}
@Override
public QName next() {
if (current.parent != null) {
final QName ret = current.qname;
current = current.parent;
return ret;
}
throw new NoSuchElementException("No more elements available");
}
};
}
/**
* Returns the immediate parent SchemaPath.
*
* @return Parent path, null if this SchemaPath is already toplevel.
*/
public SchemaPath getParent() {
return parent;
}
/**
* Get the last component of this path.
*
* @return The last component of this path.
*/
public final QName getLastComponent() {
return qname;
}
/**
* Describes whether schema path is|isn't absolute.
*
* @return boolean value which is true
if schema path is
* absolute.
*/
public abstract boolean isAbsolute();
/**
* Return this path as a {@link SchemaNodeIdentifier}.
*
* @return A SchemaNodeIdentifier.
* @throws IllegalStateException if this path is empty
*/
public final SchemaNodeIdentifier asSchemaNodeIdentifier() {
checkState(qname != null, "Cannot convert empty %s", this);
final List path = getPathFromRoot();
return isAbsolute() ? Absolute.of(path) : Descendant.of(path);
}
/**
* Return this path as an {@link Absolute} SchemaNodeIdentifier.
*
* @return An SchemaNodeIdentifier.
* @throws IllegalStateException if this path is empty or is not absolute.
*/
public final Absolute asAbsolute() {
final SchemaNodeIdentifier ret = asSchemaNodeIdentifier();
if (ret instanceof Absolute) {
return (Absolute) ret;
}
throw new IllegalStateException("Path " + this + " is relative");
}
/**
* Return this path as an {@link Descendant} SchemaNodeIdentifier.
*
* @return An SchemaNodeIdentifier.
* @throws IllegalStateException if this path is empty or is not relative.
*/
public final Descendant asDescendant() {
final SchemaNodeIdentifier ret = asSchemaNodeIdentifier();
if (ret instanceof Descendant) {
return (Descendant) ret;
}
throw new IllegalStateException("Path " + this + " is absolute");
}
@Override
public final int hashCode() {
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;
}
final SchemaPath other = (SchemaPath) obj;
return Objects.equals(qname, other.qname) && Objects.equals(parent, other.parent);
}
@Override
public final String toString() {
return MoreObjects.toStringHelper(this).add("path", getPathFromRoot()).toString();
}
}