DefaultConsumer.java

// Copyright (c) 2007-Present Pivotal Software, Inc.  All rights reserved.
//
// This software, the RabbitMQ Java client library, is triple-licensed under the
// Mozilla Public License 1.1 ("MPL"), the GNU General Public License version 2
// ("GPL") and the Apache License version 2 ("ASL"). For the MPL, please see
// LICENSE-MPL-RabbitMQ. For the GPL, please see LICENSE-GPL2.  For the ASL,
// please see LICENSE-APACHE2.
//
// This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY KIND,
// either express or implied. See the LICENSE file for specific language governing
// rights and limitations of this software.
//
// If you have any questions regarding licensing, please contact us at
// info@rabbitmq.com.


package com.rabbitmq.client;

import java.io.IOException;

/**
 * Convenience class providing a default implementation of {@link Consumer}.
 * We anticipate that most Consumer implementations will subclass this class.
 */
public class DefaultConsumer implements Consumer {
    /** Channel that this consumer is associated with. */
    private final Channel _channel;
    /** Consumer tag for this consumer. */
    private volatile String _consumerTag;

    /**
     * Constructs a new instance and records its association to the passed-in channel.
     * @param channel the channel to which this consumer is attached
     */
    public DefaultConsumer(Channel channel) {
        _channel = channel;
    }

    /**
     * Stores the most recently passed-in consumerTag - semantically, there should be only one.
     * @see Consumer#handleConsumeOk
     */
    @Override
    public void handleConsumeOk(String consumerTag) {
        this._consumerTag = consumerTag;
    }

    /**
     * No-op implementation of {@link Consumer#handleCancelOk}.
     * @param consumerTag the defined consumer tag (client- or server-generated)
     */
    @Override
    public void handleCancelOk(String consumerTag) {
        // no work to do
    }

    /**
     * No-op implementation of {@link Consumer#handleCancel(String)}
     * @param consumerTag the defined consumer tag (client- or server-generated)
     */
    @Override
    public void handleCancel(String consumerTag) throws IOException {
        // no work to do
    }

    /**
     * No-op implementation of {@link Consumer#handleShutdownSignal}.
     */
    @Override
    public void handleShutdownSignal(String consumerTag, ShutdownSignalException sig) {
        // no work to do
    }

     /**
     * No-op implementation of {@link Consumer#handleRecoverOk}.
     */
    @Override
    public void handleRecoverOk(String consumerTag) {
        // no work to do
    }

    /**
     * No-op implementation of {@link Consumer#handleDelivery}.
     */
    @Override
    public void handleDelivery(String consumerTag,
                               Envelope envelope,
                               AMQP.BasicProperties properties,
                               byte[] body)
        throws IOException
    {
            // no work to do
    }

    /**
    *  Retrieve the channel.
     * @return the channel this consumer is attached to.
     */
    public Channel getChannel() {
        return _channel;
    }

    /**
    *  Retrieve the consumer tag.
     * @return the most recently notified consumer tag.
     */
    public String getConsumerTag() {
        return _consumerTag;
    }
}