mx.bigdata.utils.amqp.ReconnectingPublisher.java Source code

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Here is the source code for mx.bigdata.utils.amqp.ReconnectingPublisher.java

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/*
 *  Copyright 2010 BigData Mx
 *
 *  Licensed under the Apache License, Version 2.0 (the "License");
 *  you may not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS,
 *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 */

package mx.bigdata.utils.amqp;

import java.io.IOException;
import java.util.Set;
import java.util.HashSet;

import com.rabbitmq.client.AMQP;
import com.rabbitmq.client.ConnectionFactory;
import com.rabbitmq.client.Channel;
import com.rabbitmq.client.Consumer;
import com.rabbitmq.client.DefaultConsumer;
import com.rabbitmq.client.QueueingConsumer;
import com.rabbitmq.client.ShutdownListener;
import com.rabbitmq.client.ShutdownSignalException;

import org.apache.log4j.Logger;

import mx.bigdata.utils.amqp.AMQPClientHelper;

public class ReconnectingPublisher {

    private final Logger logger = Logger.getLogger(getClass());

    private final ConnectionFactory factory;

    protected final String tag;

    protected final String key;

    protected final AMQPClientHelper amqp;

    protected final Set<String> declaredExchanges = new HashSet();

    private Channel out;

    public ReconnectingPublisher(String tag, String key, AMQPClientHelper amqp, ConnectionFactory factory) {
        this.tag = tag;
        this.key = key;
        this.amqp = amqp;
        this.factory = factory;
        initPublisher();
    }

    public ReconnectingPublisher(String tag, String key, AMQPClientHelper amqp) throws Exception {
        this(tag, key, amqp, amqp.createConnectionFactory(key));
    }

    private boolean initPublisher() {
        try {
            declaredExchanges.clear();
            String exchName = amqp.getExchangeName(key);
            if (exchName == null || amqp.getExchangeType(key) == null) {
                out = amqp.declareChannel(factory, key, false);
            } else {
                out = amqp.declareChannel(factory, key);
                declaredExchanges.add(exchName);
            }
            out.addShutdownListener(new ShutdownListener() {
                public void shutdownCompleted(ShutdownSignalException sig) {
                    out.getConnection().abort(10000);
                    if (!sig.isInitiatedByApplication()) {
                        logger.warn(tag + " ShutdownSignal for tag: " + tag + "\n\t reason: " + sig.getReason()
                                + "\n\t reference: " + sig.getReason() + "\n\t ", sig);
                        reconnect();
                    } else {
                        logger.debug(tag + " ShutdownSignal for tag: " + tag + "\n\t reason: " + sig.getReason());
                        out = null;
                    }
                }
            });
            logger.info("Publisher " + tag + " initialized");
            return true;
        } catch (Throwable e) {
            logger.error("Exception initializing publisher " + tag + ": ", e);
            if (out != null) {
                out.getConnection().abort(5000);
            }
        }
        return false;
    }

    public void publish(byte[] bytes) throws IOException {
        publish(null, null, bytes);
    }

    public void publish(String exchange, String routingKey, byte[] bytes) throws IOException {
        publish(exchange, routingKey, false, false, null, bytes);
    }

    public synchronized void publish(String exch, String routingKey, boolean mandatory, boolean immediate,
            AMQP.BasicProperties props, byte[] bytes) throws IOException {
        try {
            exch = (exch == null) ? amqp.getExchangeName(key) : exch;
            routingKey = (routingKey == null) ? amqp.getRoutingKey(key) : routingKey;
            if (!declaredExchanges.contains(exch)) {
                out.exchangeDeclare(exch, amqp.getExchangeType(key), true);
                declaredExchanges.add(exch);
            }
            out.basicPublish(exch, routingKey, mandatory, immediate, props, bytes);
        } catch (Exception e) {
            logger.warn(tag + " Exception while publishing: ", e);
            try {
                out.getConnection().abort(5000);
            } catch (Exception ingnore) {
            }
            if (reconnect()) {
                publish(exch, routingKey, mandatory, immediate, props, bytes);
            }
        }
    }

    protected Channel getChannel() {
        return out;
    }

    private boolean reconnect() {
        return reconnect(0, 1);
    }

    private boolean reconnect(int backoff, int pow) {
        if (out == null) {
            return false;
        }
        try {
            if (backoff > 0) {
                logger.info("Reconnecting consumer " + tag + " in " + (backoff / 1000) + " seconds ");
                Thread.sleep(backoff);
            }
        } catch (InterruptedException ignore) {
        }
        boolean initialized = initPublisher();
        if (!initialized) {
            backoff = (int) (Math.pow(2, pow));
            pow += 1;
            return reconnect(backoff, pow);
        }
        return true;
    }

    public void close() {
        out.getConnection().abort(5000);
    }
}