--- /dev/null
+/**
+ * Copyright (c) 2015 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.controller.md.sal.dom.spi;
+
+import com.google.common.base.MoreObjects;
+import com.google.common.base.Preconditions;
+import java.lang.ref.Reference;
+import java.lang.ref.WeakReference;
+import java.util.ArrayList;
+import java.util.Collection;
+import java.util.Collections;
+import java.util.HashMap;
+import java.util.Map;
+import javax.annotation.Nonnull;
+import org.opendaylight.yangtools.concepts.Identifiable;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifier;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeIdentifierWithPredicates;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.NodeWithValue;
+import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier.PathArgument;
+import org.slf4j.Logger;
+import org.slf4j.LoggerFactory;
+
+/**
+ * This is a single node within the registration tree. Note that the data returned from
+ * and instance of this class is guaranteed to have any relevance or consistency
+ * only as long as the {@link RegistrationTreeSnapshot} instance through which it is reached
+ * remains unclosed.
+ *
+ * @param <T> registration type
+ * @author Robert Varga
+ */
+public final class RegistrationTreeNode<T> implements Identifiable<PathArgument> {
+ private static final Logger LOG = LoggerFactory.getLogger(RegistrationTreeNode.class);
+
+ private final Map<PathArgument, RegistrationTreeNode<T>> children = new HashMap<>();
+ private final Collection<T> registrations = new ArrayList<>(2);
+ private final Collection<T> publicRegistrations = Collections.unmodifiableCollection(registrations);
+ private final Reference<RegistrationTreeNode<T>> parent;
+ private final PathArgument identifier;
+
+ RegistrationTreeNode(final RegistrationTreeNode<T> parent, final PathArgument identifier) {
+ this.parent = new WeakReference<>(parent);
+ this.identifier = identifier;
+ }
+
+ @Override
+ public PathArgument getIdentifier() {
+ return identifier;
+ }
+
+ /**
+ * Return the child matching a {@link PathArgument} specification.
+ *
+ * @param arg Child identifier
+ * @return Child matching exactly, or null.
+ */
+ public RegistrationTreeNode<T> getExactChild(@Nonnull final PathArgument arg) {
+ return children.get(Preconditions.checkNotNull(arg));
+ }
+
+ /**
+ * Return a collection children which match a {@link PathArgument} specification inexactly.
+ * This explicitly excludes the child returned by {@link #getExactChild(PathArgument)}.
+ *
+ * @param arg Child identifier
+ * @return Collection of children, guaranteed to be non-null.
+ */
+ public @Nonnull Collection<RegistrationTreeNode<T>> getInexactChildren(@Nonnull final PathArgument arg) {
+ Preconditions.checkNotNull(arg);
+ if (arg instanceof NodeWithValue || arg instanceof NodeIdentifierWithPredicates) {
+ /*
+ * TODO: This just all-or-nothing wildcards, which we have historically supported. Given
+ * that the argument is supposed to have all the elements filled out, we could support
+ * partial wildcards by iterating over the registrations and matching the maps for
+ * partial matches.
+ */
+ final RegistrationTreeNode<T> child = children.get(new NodeIdentifier(arg.getNodeType()));
+ if (child == null) {
+ return Collections.emptyList();
+ } else {
+ return Collections.singletonList(child);
+ }
+ } else {
+ return Collections.emptyList();
+ }
+ }
+
+ public Collection<T> getRegistrations() {
+ return publicRegistrations;
+ }
+
+ RegistrationTreeNode<T> ensureChild(@Nonnull final PathArgument child) {
+ RegistrationTreeNode<T> potential = children.get(Preconditions.checkNotNull(child));
+ if (potential == null) {
+ potential = new RegistrationTreeNode<T>(this, child);
+ children.put(child, potential);
+ }
+ return potential;
+ }
+
+ void addRegistration(@Nonnull final T registration) {
+ registrations.add(Preconditions.checkNotNull(registration));
+ LOG.debug("Registration {} added", registration);
+ }
+
+ void removeRegistration(@Nonnull final T registration) {
+ registrations.remove(Preconditions.checkNotNull(registration));
+ LOG.debug("Registration {} removed", registration);
+
+ // We have been called with the write-lock held, so we can perform some cleanup.
+ removeThisIfUnused();
+ }
+
+ private void removeThisIfUnused() {
+ final RegistrationTreeNode<T> p = parent.get();
+ if (p != null && registrations.isEmpty() && children.isEmpty()) {
+ p.removeChild(identifier);
+ }
+ }
+
+ private void removeChild(final PathArgument arg) {
+ children.remove(arg);
+ removeThisIfUnused();
+ }
+
+ @Override
+ public String toString() {
+ return MoreObjects.toStringHelper(this)
+ .add("identifier", identifier)
+ .add("registrations", registrations.size())
+ .add("children", children.size()).toString();
+ }
+}
Code Review / controller.git / blobdiff