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.controller.cluster.datastore;
10 import akka.actor.ActorRef;
11 import akka.actor.ActorSelection;
12 import java.util.ArrayList;
13 import java.util.Collection;
14 import java.util.Collections;
15 import java.util.Map.Entry;
16 import org.opendaylight.controller.cluster.datastore.messages.EnableNotification;
17 import org.opendaylight.controller.cluster.datastore.messages.RegisterDataTreeChangeListener;
18 import org.opendaylight.controller.cluster.datastore.messages.RegisterDataTreeChangeListenerReply;
19 import org.opendaylight.controller.md.sal.dom.api.DOMDataTreeChangeListener;
20 import org.opendaylight.yangtools.concepts.ListenerRegistration;
21 import org.opendaylight.yangtools.yang.data.api.schema.tree.DataTreeCandidate;
22 import org.slf4j.Logger;
23 import org.slf4j.LoggerFactory;
25 final class DataTreeChangeListenerSupport extends LeaderLocalDelegateFactory<RegisterDataTreeChangeListener, ListenerRegistration<DOMDataTreeChangeListener>, DataTreeCandidate> {
26 private static final Logger LOG = LoggerFactory.getLogger(DataTreeChangeListenerSupport.class);
27 private final ArrayList<DelayedDataTreeListenerRegistration> delayedRegistrations = new ArrayList<>();
28 private final Collection<ActorSelection> actors = new ArrayList<>();
30 DataTreeChangeListenerSupport(final Shard shard) {
35 void onLeadershipChange(final boolean isLeader) {
37 for (DelayedDataTreeListenerRegistration reg : delayedRegistrations) {
38 reg.createDelegate(this);
40 delayedRegistrations.clear();
41 delayedRegistrations.trimToSize();
44 final EnableNotification msg = new EnableNotification(isLeader);
45 for (ActorSelection dataChangeListener : actors) {
46 dataChangeListener.tell(msg, getSelf());
51 void onMessage(final RegisterDataTreeChangeListener registerTreeChangeListener, final boolean isLeader) {
52 LOG.debug("{}: registerTreeChangeListener for {}, leader: {}", persistenceId(), registerTreeChangeListener.getPath(), isLeader);
54 final ListenerRegistration<DOMDataTreeChangeListener> registration;
55 final DataTreeCandidate event;
57 LOG.debug("{}: Shard is not the leader - delaying registration", persistenceId());
59 DelayedDataTreeListenerRegistration delayedReg =
60 new DelayedDataTreeListenerRegistration(registerTreeChangeListener);
61 delayedRegistrations.add(delayedReg);
62 registration = delayedReg;
65 final Entry<ListenerRegistration<DOMDataTreeChangeListener>, DataTreeCandidate> res = createDelegate(registerTreeChangeListener);
66 registration = res.getKey();
67 event = res.getValue();
70 ActorRef listenerRegistration = createActor(DataTreeChangeListenerRegistrationActor.props(registration));
72 LOG.debug("{}: registerDataChangeListener sending reply, listenerRegistrationPath = {} ",
73 persistenceId(), listenerRegistration.path());
75 tellSender(new RegisterDataTreeChangeListenerReply(listenerRegistration));
77 registration.getInstance().onDataTreeChanged(Collections.singletonList(event));
82 Entry<ListenerRegistration<DOMDataTreeChangeListener>, DataTreeCandidate> createDelegate(final RegisterDataTreeChangeListener message) {
83 ActorSelection dataChangeListenerPath = selectActor(message.getDataTreeChangeListenerPath());
85 // Notify the listener if notifications should be enabled or not
86 // If this shard is the leader then it will enable notifications else
88 dataChangeListenerPath.tell(new EnableNotification(true), getSelf());
90 // Now store a reference to the data change listener so it can be notified
91 // at a later point if notifications should be enabled or disabled
92 actors.add(dataChangeListenerPath);
94 DOMDataTreeChangeListener listener = new ForwardingDataTreeChangeListener(dataChangeListenerPath);
96 LOG.debug("{}: Registering for path {}", persistenceId(), message.getPath());
98 return getShard().getDataStore().registerTreeChangeListener(message.getPath(), listener);