/*
* JBoss, Home of Professional Open Source
* Copyright 2010 Red Hat Inc. and/or its affiliates and other
* contributors as indicated by the @author tags. All rights reserved.
* See the copyright.txt in the distribution for a full listing of
* individual contributors.
*
* This is free software; you can redistribute it and/or modify it
* under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This software is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this software; if not, write to the Free
* Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
* 02110-1301 USA, or see the FSF site: http://www.fsf.org.
*/
package org.infinispan.server.websocket;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.CopyOnWriteArrayList;
import org.infinispan.Cache;
import org.infinispan.notifications.Listener;
import org.infinispan.notifications.cachelistener.annotation.CacheEntryCreated;
import org.infinispan.notifications.cachelistener.annotation.CacheEntryModified;
import org.infinispan.notifications.cachelistener.annotation.CacheEntryRemoved;
import org.infinispan.notifications.cachelistener.event.CacheEntryCreatedEvent;
import org.infinispan.notifications.cachelistener.event.CacheEntryEvent;
import org.infinispan.notifications.cachelistener.event.CacheEntryModifiedEvent;
import org.infinispan.notifications.cachelistener.event.CacheEntryRemovedEvent;
import org.infinispan.notifications.cachelistener.event.Event;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.ChannelFutureListener;
import org.jboss.netty.handler.codec.http.websocketx.TextWebSocketFrame;
import org.json.JSONException;
import org.json.JSONObject;
/**
* Cache listener.
* <p/>
* Used to notify websocket clients of cache entry updates.
*
* @author <a href="mailto:tom.fennelly@gmail.com">tom.fennelly@gmail.com</a>
*/
@Listener
public class CacheListener {
private List<ChannelNotifyParams> channels = new CopyOnWriteArrayList<ChannelNotifyParams>();
@CacheEntryCreated
public void cacheEntryCreated(CacheEntryCreatedEvent<Object, Object> event) {
notifyChannels(event, event.getType());
}
@CacheEntryModified
public void cacheEntryModified(CacheEntryModifiedEvent<Object, Object> event) {
notifyChannels(event, event.getType());
}
@CacheEntryRemoved
public void cacheEntryRemoved(CacheEntryRemovedEvent<Object, Object> event) {
notifyChannels(event, event.getType());
}
private void notifyChannels(CacheEntryEvent<Object, Object> event, Event.Type eventType) {
if(event.isPre()) {
return;
}
JSONObject jsonObject;
try {
Cache<Object, Object> cache = event.getCache();
Object key = event.getKey();
Object value;
switch(eventType) {
case CACHE_ENTRY_CREATED:
// TODO: Add optimization ... don't get from cache if non of the channels are interested in creates...
value = cache.get(key);
jsonObject = ChannelUtils.toJSON(key.toString(), value, cache.getName());
break;
case CACHE_ENTRY_MODIFIED:
value = ((CacheEntryModifiedEvent<Object, Object>)event).getValue();
jsonObject = ChannelUtils.toJSON(key.toString(), value, cache.getName());
break;
case CACHE_ENTRY_REMOVED:
jsonObject = ChannelUtils.toJSON(key.toString(), null, cache.getName());
break;
default:
return;
}
jsonObject.put("eventType", eventType.toString());
} catch (JSONException e) {
return;
}
String jsonString = jsonObject.toString();
for(ChannelNotifyParams channel : channels) {
if(channel.channel.isOpen() && channel.onEvents.contains(eventType)) {
if(channel.key != null) {
if(event.getKey().equals(channel.key) || channel.key.equals("*")) {
channel.channel.write(new TextWebSocketFrame(jsonString));
}
} else {
channel.channel.write(new TextWebSocketFrame(jsonString));
}
}
}
}
public void addChannel(ChannelNotifyParams channel) {
if(!channels.contains(channel)) {
channels.add(channel);
channel.channel.getCloseFuture().addListener(new ChannelCloseFutureListener());
}
}
public void removeChannel(ChannelNotifyParams channel) {
channels.remove(channel);
}
public static class ChannelNotifyParams {
private static final String[] DEFAULT_EVENTS = {Event.Type.CACHE_ENTRY_MODIFIED.toString(), Event.Type.CACHE_ENTRY_REMOVED.toString()};
private Channel channel;
private String key;
private List<Event.Type> onEvents = new ArrayList<Event.Type>();
public ChannelNotifyParams(Channel channel, String key, String[] onEvents) {
if(channel == null) {
throw new IllegalArgumentException("null 'channel' arg in constructor call.");
}
String[] onEventsSpec = onEvents;
this.channel = channel;
this.key = key;
if(onEventsSpec == null) {
onEventsSpec = DEFAULT_EVENTS;
}
for(String eventType : onEventsSpec) {
try {
this.onEvents.add(Event.Type.valueOf(eventType));
} catch(RuntimeException e) {
// Ignore for now
}
}
if(onEvents == null && key.equals("*")) {
this.onEvents.add(Event.Type.CACHE_ENTRY_CREATED);
}
}
@Override
public boolean equals(Object obj) {
if(obj instanceof ChannelNotifyParams) {
ChannelNotifyParams channelNotifyParams = (ChannelNotifyParams) obj;
if(channelNotifyParams.channel == channel) {
if(key == null) {
return (channelNotifyParams.key == null);
} else {
return key.equals(channelNotifyParams.key);
}
}
}
return false;
}
@Override
public int hashCode() {
if(key != null) {
return super.hashCode() + channel.hashCode() + key.hashCode();
} else {
return super.hashCode() + channel.hashCode();
}
}
}
private class ChannelCloseFutureListener implements ChannelFutureListener {
@Override
public void operationComplete(ChannelFuture channelCloseFuture) throws Exception {
for(ChannelNotifyParams channel : channels) {
if(channelCloseFuture.getChannel() == channel.channel) {
removeChannel(channel);
}
}
}
}
}