org.springframework.amqp.rabbit.connection.RabbitResourceHolder.java Source code

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Here is the source code for org.springframework.amqp.rabbit.connection.RabbitResourceHolder.java

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/*
 * Copyright 2002-2014 the original author or authors.
 *
 * 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 org.springframework.amqp.rabbit.connection;

import java.io.IOException;
import java.util.HashMap;
import java.util.LinkedList;
import java.util.List;
import java.util.Map;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

import org.springframework.amqp.AmqpException;
import org.springframework.amqp.AmqpIOException;
import org.springframework.amqp.rabbit.core.RabbitTemplate;
import org.springframework.amqp.rabbit.transaction.RabbitTransactionManager;
import org.springframework.transaction.support.ResourceHolderSupport;
import org.springframework.util.Assert;
import org.springframework.util.CollectionUtils;
import org.springframework.util.LinkedMultiValueMap;
import org.springframework.util.MultiValueMap;

import com.rabbitmq.client.Channel;

/**
 * Rabbit resource holder, wrapping a RabbitMQ Connection and Channel. RabbitTransactionManager binds instances of this
 * class to the thread, for a given Rabbit ConnectionFactory.
 *
 * <p>
 * Note: This is an SPI class, not intended to be used by applications.
 *
 * @author Mark Fisher
 * @author Dave Syer
 * @author Gary Russell
 *
 * @see RabbitTransactionManager
 * @see RabbitTemplate
 */
public class RabbitResourceHolder extends ResourceHolderSupport {

    private static final Log logger = LogFactory.getLog(RabbitResourceHolder.class);

    private final boolean frozen = false;

    private final List<Connection> connections = new LinkedList<Connection>();

    private final List<Channel> channels = new LinkedList<Channel>();

    private final Map<Connection, List<Channel>> channelsPerConnection = new HashMap<Connection, List<Channel>>();

    private final MultiValueMap<Channel, Long> deliveryTags = new LinkedMultiValueMap<Channel, Long>();

    private boolean transactional;

    private boolean releaseAfterCompletion = true;

    /**
     * Create a new RabbitResourceHolder that is open for resources to be added.
     */
    public RabbitResourceHolder() {
    }

    /**
     * @param channel a channel to add
     * @param releaseAfterCompletion true if the channel should be released after completion.
     */
    public RabbitResourceHolder(Channel channel, boolean releaseAfterCompletion) {
        this();
        addChannel(channel);
        this.releaseAfterCompletion = releaseAfterCompletion;
    }

    public final boolean isFrozen() {
        return this.frozen;
    }

    /**
     * Whether the resources should be released after transaction completion.
     * Default true. Listener containers set to false because the listener continues
     * to use the channel.
     *
     * @return true if the resources should be released.
     */
    public boolean isReleaseAfterCompletion() {
        return releaseAfterCompletion;
    }

    public final void addConnection(Connection connection) {
        Assert.isTrue(!this.frozen, "Cannot add Connection because RabbitResourceHolder is frozen");
        Assert.notNull(connection, "Connection must not be null");
        if (!this.connections.contains(connection)) {
            this.connections.add(connection);
        }
    }

    public final void addChannel(Channel channel) {
        addChannel(channel, null);
    }

    public final void addChannel(Channel channel, Connection connection) {
        Assert.isTrue(!this.frozen, "Cannot add Channel because RabbitResourceHolder is frozen");
        Assert.notNull(channel, "Channel must not be null");
        if (!this.channels.contains(channel)) {
            this.channels.add(channel);
            if (connection != null) {
                List<Channel> channels = this.channelsPerConnection.get(connection);
                if (channels == null) {
                    channels = new LinkedList<Channel>();
                    this.channelsPerConnection.put(connection, channels);
                }
                channels.add(channel);
            }
        }
    }

    public boolean containsChannel(Channel channel) {
        return this.channels.contains(channel);
    }

    public Connection getConnection() {
        return (!this.connections.isEmpty() ? this.connections.get(0) : null);
    }

    public Connection getConnection(Class<? extends Connection> connectionType) {
        return CollectionUtils.findValueOfType(this.connections, connectionType);
    }

    public Channel getChannel() {
        return (!this.channels.isEmpty() ? this.channels.get(0) : null);
    }

    public void commitAll() throws AmqpException {
        try {
            for (Channel channel : this.channels) {
                if (deliveryTags.containsKey(channel)) {
                    for (Long deliveryTag : deliveryTags.get(channel)) {
                        channel.basicAck(deliveryTag, false);
                    }
                }
                channel.txCommit();
            }
        } catch (IOException e) {
            throw new AmqpException("failed to commit RabbitMQ transaction", e);
        }
    }

    public void closeAll() {
        for (Channel channel : this.channels) {
            try {
                if (channel != ConsumerChannelRegistry.getConsumerChannel()) {
                    channel.close();
                } else {
                    if (logger.isDebugEnabled()) {
                        logger.debug("Skipping close of consumer channel: " + channel.toString());
                    }
                }
            } catch (Throwable ex) {
                logger.debug("Could not close synchronized Rabbit Channel after transaction", ex);
            }
        }
        for (Connection con : this.connections) {
            RabbitUtils.closeConnection(con);
        }
        this.connections.clear();
        this.channels.clear();
        this.channelsPerConnection.clear();
    }

    public void addDeliveryTag(Channel channel, long deliveryTag) {
        this.deliveryTags.add(channel, deliveryTag);
    }

    public void rollbackAll() {
        for (Channel channel : this.channels) {
            if (logger.isDebugEnabled()) {
                logger.debug("Rolling back messages to channel: " + channel);
            }
            RabbitUtils.rollbackIfNecessary(channel);
            if (deliveryTags.containsKey(channel)) {
                for (Long deliveryTag : deliveryTags.get(channel)) {
                    try {
                        channel.basicReject(deliveryTag, true);
                    } catch (IOException ex) {
                        throw new AmqpIOException(ex);
                    }
                }
                // Need to commit the reject (=nack)
                RabbitUtils.commitIfNecessary(channel);
            }
        }
    }

    /**
     * @return true if the channels in this holder are transactional
     */
    public boolean isChannelTransactional() {
        return this.transactional;
    }

}