opendaylight/md-sal/sal-dom-broker/src/main/java/org/opendaylight/controller/md/sal/dom/broker/impl/DOMNotificationRouterEvent.java

   1 /*
   2  * Copyright (c) 2014 Cisco Systems, Inc. and others.  All rights reserved.
   3  *
   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
   7  */
   8 package org.opendaylight.controller.md.sal.dom.broker.impl;
   9
  10 import com.google.common.base.Preconditions;
  11 import com.google.common.util.concurrent.ListenableFuture;
  12 import com.google.common.util.concurrent.SettableFuture;
  13 import com.lmax.disruptor.EventFactory;
  14 import java.util.Collection;
  15 import org.opendaylight.controller.md.sal.dom.api.DOMNotification;
  16 import org.opendaylight.controller.md.sal.dom.api.DOMNotificationListener;
  17 import org.opendaylight.yangtools.concepts.ListenerRegistration;
  18 import org.slf4j.Logger;
  19 import org.slf4j.LoggerFactory;
  20
  21 /**
  22  * A single notification event in the disruptor ringbuffer. These objects are reused,
  23  * so they do have mutable state.
  24  */
  25 final class DOMNotificationRouterEvent {
  26     private static final Logger LOG = LoggerFactory.getLogger(DOMNotificationRouterEvent.class);
  27     public static final EventFactory<DOMNotificationRouterEvent> FACTORY = DOMNotificationRouterEvent::new;
  28
  29     private Collection<ListenerRegistration<? extends DOMNotificationListener>> subscribers;
  30     private DOMNotification notification;
  31     private SettableFuture<Void> future;
  32
  33     private DOMNotificationRouterEvent() {
  34         // Hidden on purpose, initialized in initialize()
  35     }
  36
  37     ListenableFuture<Void> initialize(final DOMNotification notification, final Collection<ListenerRegistration<? extends DOMNotificationListener>> subscribers) {
  38         this.notification = Preconditions.checkNotNull(notification);
  39         this.subscribers = Preconditions.checkNotNull(subscribers);
  40         this.future = SettableFuture.create();
  41         return this.future;
  42     }
  43
  44     void deliverNotification() {
  45         LOG.trace("Start delivery of notification {}", notification);
  46         for (ListenerRegistration<? extends DOMNotificationListener> r : subscribers) {
  47             final DOMNotificationListener listener = r.getInstance();
  48             if (listener != null) {
  49                 try {
  50                     LOG.trace("Notifying listener {}", listener);
  51                     listener.onNotification(notification);
  52                     LOG.trace("Listener notification completed");
  53                 } catch (Exception e) {
  54                     LOG.error("Delivery of notification {} caused an error in listener {}", notification, listener, e);
  55                 }
  56             }
  57         }
  58         LOG.trace("Delivery completed");
  59     }
  60
  61     void setFuture() {
  62         future.set(null);
  63         notification = null;
  64         subscribers = null;
  65         future = null;
  66     }
  67 }