/*
* 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.schema.tree;
import com.google.common.annotations.Beta;
import com.google.common.base.Optional;
import com.google.common.base.Predicate;
import com.google.common.base.Predicates;
import com.google.common.base.Verify;
import java.util.AbstractMap.SimpleImmutableEntry;
import java.util.Iterator;
import java.util.Map.Entry;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
/**
* A set of utility methods for interacting with {@link StoreTreeNode} objects.
*/
@Beta
public final class StoreTreeNodes {
private StoreTreeNodes() {
throw new UnsupportedOperationException("Utility class should not be instantiated");
}
/**
* Finds a node in tree
* @param <T>
* Store tree node type.
* @param tree Data Tree
* @param path Path to the node
* @return Optional with node if the node is present in tree, {@link Optional#absent()} otherwise.
*/
public static <T extends StoreTreeNode<T>> Optional<T> findNode(final T tree, final YangInstanceIdentifier path) {
Optional<T> current = Optional.of(tree);
Iterator<PathArgument> pathIter = path.getPathArguments().iterator();
while (current.isPresent() && pathIter.hasNext()) {
current = current.get().getChild(pathIter.next());
}
return current;
}
public static <T extends StoreTreeNode<T>> T findNodeChecked(final T tree, final YangInstanceIdentifier path) {
T current = tree;
int i = 1;
for (PathArgument pathArg : path.getPathArguments()) {
Optional<T> potential = current.getChild(pathArg);
if (!potential.isPresent()) {
throw new IllegalArgumentException(String.format("Child %s is not present in tree.",
path.getAncestor(i)));
}
current = potential.get();
++i;
}
return current;
}
/**
* Finds a node or closest parent in the tree
* @param <T>
* Store tree node type.
* @param tree Data Tree
* @param path Path to the node
* @return Map.Entry Entry with key which is path to closest parent and value is parent node.
*
*/
public static <T extends StoreTreeNode<T>> Entry<YangInstanceIdentifier, T> findClosest(final T tree,
final YangInstanceIdentifier path) {
return findClosestsOrFirstMatch(tree, path, Predicates.alwaysFalse());
}
public static <T extends StoreTreeNode<T>> Entry<YangInstanceIdentifier, T> findClosestsOrFirstMatch(final T tree,
final YangInstanceIdentifier path, final Predicate<T> predicate) {
Optional<T> parent = Optional.of(tree);
Optional<T> current = Optional.of(tree);
int nesting = 0;
Iterator<PathArgument> pathIter = path.getPathArguments().iterator();
while (current.isPresent() && pathIter.hasNext() && !predicate.apply(current.get())) {
parent = current;
current = current.get().getChild(pathIter.next());
nesting++;
}
if (current.isPresent()) {
final YangInstanceIdentifier currentPath = path.getAncestor(nesting);
return new SimpleImmutableEntry<>(currentPath, current.get());
}
/*
* Subtracting 1 from nesting level at this point is safe, because we
* cannot reach here with nesting == 0: that would mean the above check
* for current.isPresent() failed, which it cannot, as current is always
* present. At any rate we verify state just to be on the safe side.
*/
Verify.verify(nesting > 0);
return new SimpleImmutableEntry<>(path.getAncestor(nesting - 1), parent.get());
}
public static <T extends StoreTreeNode<T>> Optional<T> getChild(final Optional<T> parent, final PathArgument child) {
if (parent.isPresent()) {
return parent.get().getChild(child);
}
return Optional.absent();
}
}