restconf/restconf-nb-bierman02/src/main/java/org/opendaylight/netconf/sal/streams/listeners/EventBusChangeRecorder.java

   1 /*
   2  * Copyright (c) 2016 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.netconf.sal.streams.listeners;
   9
  10 import com.google.common.eventbus.Subscribe;
  11 import io.netty.channel.Channel;
  12 import io.netty.handler.codec.http.websocketx.TextWebSocketFrame;
  13 import org.slf4j.Logger;
  14 import org.slf4j.LoggerFactory;
  15
  16 class EventBusChangeRecorder<T extends BaseListenerInterface> {
  17
  18     private static final Logger LOG = LoggerFactory.getLogger(EventBusChangeRecorder.class);
  19     private final T listener;
  20
  21     /**
  22      * Event bus change recorder of specific listener of notifications.
  23      *
  24      * @param listener
  25      *             specific listener
  26      */
  27     EventBusChangeRecorder(final T listener) {
  28         this.listener = listener;
  29     }
  30
  31     @Subscribe
  32     public void recordCustomerChange(final Event event) {
  33         if (event.getType() == EventType.REGISTER) {
  34             final Channel subscriber = event.getSubscriber();
  35             if (!this.listener.getSubscribers().contains(subscriber)) {
  36                 this.listener.getSubscribers().add(subscriber);
  37             }
  38         } else if (event.getType() == EventType.DEREGISTER) {
  39             this.listener.getSubscribers().remove(event.getSubscriber());
  40             Notificator.removeListenerIfNoSubscriberExists(this.listener);
  41         } else if (event.getType() == EventType.NOTIFY) {
  42             for (final Channel subscriber : this.listener.getSubscribers()) {
  43                 if (subscriber.isActive()) {
  44                     LOG.debug("Data are sent to subscriber {}:", subscriber.remoteAddress());
  45                     subscriber.writeAndFlush(new TextWebSocketFrame(event.getData()));
  46                 } else {
  47                     LOG.debug("Subscriber {} is removed - channel is not active yet.", subscriber.remoteAddress());
  48                     this.listener.getSubscribers().remove(subscriber);
  49                 }
  50             }
  51         }
  52     }
  53 }