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 com.google.common.base.Preconditions;
11 import javax.annotation.concurrent.GuardedBy;
12 import org.opendaylight.controller.cluster.datastore.messages.RegisterDataTreeChangeListener;
13 import org.opendaylight.controller.md.sal.dom.api.DOMDataTreeChangeListener;
14 import org.opendaylight.yangtools.concepts.ListenerRegistration;
17 * Intermediate proxy registration returned to the user when we cannot
18 * instantiate the registration immediately. It provides a bridge to
19 * a real registration which may materialize at some point in the future.
21 final class DelayedDataTreeListenerRegistration implements ListenerRegistration<DOMDataTreeChangeListener> {
22 private final RegisterDataTreeChangeListener registerTreeChangeListener;
23 private volatile ListenerRegistration<DOMDataTreeChangeListener> delegate;
25 private boolean closed;
27 DelayedDataTreeListenerRegistration(final RegisterDataTreeChangeListener registerTreeChangeListener) {
28 this.registerTreeChangeListener = Preconditions.checkNotNull(registerTreeChangeListener);
31 synchronized void createDelegate(final DelegateFactory<RegisterDataTreeChangeListener, ListenerRegistration<DOMDataTreeChangeListener>> factory) {
33 this.delegate = factory.createDelegate(registerTreeChangeListener);
38 public DOMDataTreeChangeListener getInstance() {
39 final ListenerRegistration<DOMDataTreeChangeListener> d = delegate;
40 return d == null ? null : d.getInstance();
44 public synchronized void close() {
47 if (delegate != null) {