org.jactr.tools.tracer.sinks.NetworkedSink.java Source code

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Here is the source code for org.jactr.tools.tracer.sinks.NetworkedSink.java

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/*
 * Created on Feb 22, 2007 Copyright (C) 2001-6, Anthony Harrison anh23@pitt.edu
 * (jactr.org) This library 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 library 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
 * library; if not, write to the Free Software Foundation, Inc., 59 Temple
 * Place, Suite 330, Boston, MA 02111-1307 USA
 */
package org.jactr.tools.tracer.sinks;

import java.util.Collection;
import java.util.Collections;
import java.util.concurrent.RejectedExecutionException;
import java.util.concurrent.ScheduledExecutorService;
import java.util.concurrent.TimeUnit;

import javolution.util.FastList;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
import org.jactr.core.concurrent.ExecutorServices;
import org.jactr.tools.async.controller.RemoteIOHandler;
import org.jactr.tools.async.controller.RemoteInterface;
import org.jactr.tools.async.message.BulkMessage;
import org.jactr.tools.async.message.IMessage;
import org.jactr.tools.tracer.ITraceSink;
import org.jactr.tools.tracer.transformer.ITransformedEvent;

/**
 * @author developer
 */
public class NetworkedSink implements ITraceSink {
    /**
     * logger definition
     */
    static private final Log LOGGER = LogFactory.getLog(NetworkedSink.class);

    private long _maximumDelay = 500; // ms

    private int MAXIMUM_BUFFER_SIZE = 25;

    private RemoteIOHandler _handler;

    private Collection<IMessage> _messageBuffer;

    private Runnable _autoFlush;

    private volatile boolean _scheduled = false;

    public NetworkedSink() {
        RemoteInterface ri = RemoteInterface.getActiveRemoteInterface();
        if (ri == null)
            throw new RuntimeException("A RemoteInterface must be active before instantiating this sink");
        _handler = ri.getHandler();

        try {
            MAXIMUM_BUFFER_SIZE = Integer.parseInt(System.getProperty("jACTR:MaximumBufferSize"));
        } catch (NumberFormatException nfe) {
            MAXIMUM_BUFFER_SIZE = 25;
        }

        _messageBuffer = Collections.synchronizedCollection(new FastList<IMessage>());

        _autoFlush = new Runnable() {

            public void run() {
                // no need for this to be safe..
                _scheduled = false;
                try {
                    flush();
                } catch (Exception e) {
                    LOGGER.error(".run threw Exception : ", e);
                }
            }

        };
    }

    protected boolean shouldFlush() {
        synchronized (_messageBuffer) {
            return _messageBuffer.size() >= MAXIMUM_BUFFER_SIZE;
        }
    }

    /*
     * use a delay to trigger the flush..
     */
    protected void scheduleFlush(long delay) {
        if (_scheduled)
            return;
        _scheduled = true;

        ScheduledExecutorService executor = (ScheduledExecutorService) ExecutorServices
                .getExecutor(ExecutorServices.PERIODIC);
        try {
            executor.schedule(_autoFlush, delay, TimeUnit.MILLISECONDS);
        } catch (RejectedExecutionException ree) {
            if (LOGGER.isDebugEnabled())
                LOGGER.debug(String.format("Networked flush rejected, probably in the mids of shutdown"), ree);
        }
    }

    /**
     * @see org.jactr.tools.tracer.ITraceSink#add(org.jactr.tools.tracer.transformer.ITransformedEvent)
     */
    public void add(ITransformedEvent event) {
        if (event == null) {
            LOGGER.error("null message received ", new NullPointerException());
            return;
        }
        _messageBuffer.add(event);
        if (shouldFlush())
            try {
                flush();
            } catch (Exception e) {
                LOGGER.error("Could not flush after capacity is exceeded ", e);
            }
        else
            scheduleFlush(_maximumDelay);
    }

    /**
     * @see org.jactr.tools.tracer.ITraceSink#flush()
     */
    public void flush() throws Exception {
        if (!isOpen()) {
            _messageBuffer.clear();
            return;
        }

        BulkMessage message = null;
        synchronized (_messageBuffer) {
            if (_messageBuffer.size() > 0) {
                message = new BulkMessage(_messageBuffer);
                _messageBuffer.clear();
            }
        }

        if (message != null) {
            if (LOGGER.isDebugEnabled())
                LOGGER.debug("Sending bulk message " + message.getSize());
            _handler.write(message);
        }
    }

    public boolean isOpen() {
        return _handler.isConnected();
    }
}