/**
* Helios, OpenSource Monitoring
* Brought to you by the Helios Development Group
*
* Copyright 2007, Helios Development Group and individual contributors
* as indicated by the @author tags. See the copyright.txt file 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.helios.apmrouter.server.unification.pipeline2;
import java.util.ArrayList;
import java.util.List;
import java.util.concurrent.atomic.AtomicLong;
import org.helios.apmrouter.server.ServerComponent;
import org.helios.apmrouter.util.NettyUtil;
import org.jboss.netty.buffer.ChannelBuffer;
import org.jboss.netty.buffer.CompositeChannelBuffer;
import org.jboss.netty.buffer.DirectChannelBufferFactory;
import org.jboss.netty.channel.Channel;
import org.jboss.netty.channel.ChannelEvent;
import org.jboss.netty.channel.ChannelFuture;
import org.jboss.netty.channel.ChannelFutureListener;
import org.jboss.netty.channel.ChannelHandlerContext;
import org.jboss.netty.channel.ChannelLocal;
import org.jboss.netty.channel.ChannelUpstreamHandler;
import org.jboss.netty.channel.UpstreamMessageEvent;
import org.springframework.jmx.export.annotation.ManagedMetric;
import org.springframework.jmx.support.MetricType;
/**
* <p>Title: FlushOnCloseBufferAggregator</p>
* <p>Description: An upstream channel buffer aggregator that accumulates upstream message events if they are {@link ChannelBuffer}s
* and then flushes the accumulated buffer on channel close.</p>
* <p>Company: Helios Development Group LLC</p>
* @author Whitehead (nwhitehead AT heliosdev DOT org)
* <p><code>org.helios.apmrouter.server.unification.pipeline2.FlushOnCloseBufferAggregator</code></p>
*/
public class FlushOnCloseBufferAggregator extends ServerComponent implements ChannelUpstreamHandler {
/** The singleton instance */
private static volatile FlushOnCloseBufferAggregator instance = null;
/** The singleton ctor lock */
private static final Object lock = new Object();
/** The buffer factory to create aggregated sub-buffers for the dynamic channel buffer */
private final DirectChannelBufferFactory channelBufferFactory = new DirectChannelBufferFactory();
/** The dynamic buffer channel local into which all content is aggregated */
private final ChannelLocal<List<ChannelBuffer>> aggregation = new ChannelLocal<List<ChannelBuffer>>(false);
/** A counter of aggregations in flight */
private final AtomicLong inflight = new AtomicLong(0L);
/**
* Acquires the FlushOnCloseBufferAggregator singleton instance
* @return the FlushOnCloseBufferAggregator singleton instance
*/
public static FlushOnCloseBufferAggregator getInstance() {
if(instance==null) {
synchronized(lock) {
if(instance==null) {
instance = new FlushOnCloseBufferAggregator();
}
}
}
return instance;
}
/**
* Creates a new FlushOnCloseBufferAggregator
*/
private FlushOnCloseBufferAggregator() {
}
/**
* {@inheritDoc}
* @see org.jboss.netty.channel.ChannelUpstreamHandler#handleUpstream(org.jboss.netty.channel.ChannelHandlerContext, org.jboss.netty.channel.ChannelEvent)
*/
@Override
public void handleUpstream(final ChannelHandlerContext ctx, ChannelEvent e) throws Exception {
if(e instanceof UpstreamMessageEvent) {
Object msg = ((UpstreamMessageEvent)e).getMessage();
if(msg instanceof ChannelBuffer) {
incr("ChannelBuffersProcessed");
final ChannelBuffer buff = (ChannelBuffer)msg;
final Channel channel = e.getChannel();
List<ChannelBuffer> aggBuffs = aggregation.get(channel);
buff.readerIndex(0);
if(aggBuffs==null) {
log.info("Starting aggregation with content:\n" + NettyUtil.formatBuffer(buff, 100));
inflight.incrementAndGet();
aggBuffs = new ArrayList<ChannelBuffer>();
writeBufferToAggregation(buff, aggBuffs);
aggregation.set(channel, aggBuffs);
// starting a new aggregation, so add a close handler
channel.getCloseFuture().addListener(new ChannelFutureListener() {
@Override
public void operationComplete(ChannelFuture future) throws Exception {
Thread t = new Thread("OnCloseFlushThread") {
@Override
public void run() {
try {
try {
log.info("Pausing to allow buffers to complete");
Thread.currentThread().join(3000);
} catch (Exception ex) {
}
log.info("Flushing aggregation....");
List<ChannelBuffer> aggregatedChannelBuffers = aggregation.get(channel);
ChannelBuffer totalAggregate = new CompositeChannelBuffer(buff.order(), aggregatedChannelBuffers,true);
log.info("Aggregated CompositeChannelBuffer from [" + aggregatedChannelBuffers.size() + "] buffers to [" + totalAggregate.readableBytes() + "] readable bytes");
ctx.sendUpstream(new UpstreamMessageEvent(channel, totalAggregate, channel.getRemoteAddress()));
incr("CompletedAggregations");
} finally {
inflight.decrementAndGet();
aggregation.remove(channel);
}
}
};
t.setDaemon(true);
t.start();
}
});
} else {
writeBufferToAggregation(buff, aggBuffs);
}
return;
}
}
ctx.sendUpstream(e);
}
/**
* Transfers the incoming channel buffer to a new direct allocated channel of the same size which is then added to the aggregate.
* @param incoming The incoming channel buffer
* @param target The target aggregate to add the newly allocated buffer to
*/
protected void writeBufferToAggregation(ChannelBuffer incoming, List<ChannelBuffer> target) {
ChannelBuffer dbuff = channelBufferFactory.getBuffer(incoming.order(), incoming.readableBytes());
dbuff.writeBytes(incoming);
target.add(dbuff);
}
/** The name of this decoder in the pipeline */
public static final String PIPE_NAME = "FlushOnCloseBufferAggregator";
/**
* Reutrns the number of inflight aggregations
* @return the number of inflight aggregations
*/
@ManagedMetric(category="FlushOnCloseBufferAggregator", displayName="InflightAggregations", metricType=MetricType.GAUGE, description="The number of inflight aggregations")
public long getInflightAggregations() {
return inflight.get();
}
/**
* Reutrns the number of completed aggregations
* @return the number of completed aggregations
*/
@ManagedMetric(category="FlushOnCloseBufferAggregator", displayName="CompletedAggregations", metricType=MetricType.COUNTER, description="The number of completed aggregations")
public long getCompletedAggregations() {
return getMetricValue("CompletedAggregations");
}
/**
* Reutrns the number of upstream channel buffers processed
* @return the number of upstream channel buffers processed
*/
@ManagedMetric(category="FlushOnCloseBufferAggregator", displayName="ChannelBuffersProcessed", metricType=MetricType.COUNTER, description="The number of upstream channel buffers processed")
public long getChannelBuffersProcessed() {
return getMetricValue("ChannelBuffersProcessed");
}
}