consumermanagerimpl.java

来自「OpenJMS是一个开源的Java Message Service API 1.」· Java 代码 · 共 919 行 · 第 1/3 页

/**
 * Redistribution and use of this software and associated documentation
 * ("Software"), with or without modification, are permitted provided
 * that the following conditions are met:
 *
 * 1. Redistributions of source code must retain copyright
 *    statements and notices.  Redistributions must also contain a
 *    copy of this document.
 *
 * 2. Redistributions in binary form must reproduce the
 *    above copyright notice, this list of conditions and the
 *    following disclaimer in the documentation and/or other
 *    materials provided with the distribution.
 *
 * 3. The name "Exolab" must not be used to endorse or promote
 *    products derived from this Software without prior written
 *    permission of Exoffice Technologies.  For written permission,
 *    please contact [e-mail].
 *
 * 4. Products derived from this Software may not be called "Exolab"
 *    nor may "Exolab" appear in their names without prior written
 *    permission of Exoffice Technologies. Exolab is a registered
 *    trademark of Exoffice Technologies.
 *
 * 5. Due credit should be given to the Exolab Project
 *    (http://www.exolab.org/).
 *
 * THIS SOFTWARE IS PROVIDED BY EXOFFICE TECHNOLOGIES AND CONTRIBUTORS
 * ``AS IS'' AND ANY EXPRESSED OR IMPLIED WARRANTIES, INCLUDING, BUT
 * NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL
 * EXOFFICE TECHNOLOGIES OR ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT,
 * INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES
 * (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR
 * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT,
 * STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Copyright 2001-2005 (C) Exoffice Technologies Inc. All Rights Reserved.
 *
 * $Id: ConsumerManagerImpl.java,v 1.3 2005/12/23 12:17:25 tanderson Exp $
 */
package org.exolab.jms.messagemgr;

import java.sql.Connection;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.Iterator;
import java.util.List;
import javax.jms.InvalidDestinationException;
import javax.jms.InvalidSelectorException;
import javax.jms.JMSException;

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

import org.exolab.jms.client.JmsDestination;
import org.exolab.jms.client.JmsQueue;
import org.exolab.jms.client.JmsTopic;
import org.exolab.jms.persistence.DatabaseService;
import org.exolab.jms.persistence.PersistenceAdapter;
import org.exolab.jms.persistence.PersistenceException;
import org.exolab.jms.service.Service;
import org.exolab.jms.service.ServiceException;


/**
 * The consumer manager is responsible for creating and managing the lifecycle
 * of consumers. The consumer manager maintains a list of all active consumers.
 *
 * @author <a href="mailto:[e-mail]">Jim Alateras</a>
 * @author <a href="mailto:[e-mail]">Tim Anderson</a>
 * @version $Revision: 1.3 $ $Date: 2005/12/23 12:17:25 $
 */
public class ConsumerManagerImpl extends Service implements ConsumerManager {

    /**
     * The destination manager.
     */
    private final DestinationManager _destinations;

    /**
     * The database service.
     */
    private final DatabaseService _database;

    /**
     * Maintains a list of all consumers, durable and non-durable. All durable
     * subscribers are maintained in memory until they are removed from the
     * system entirely. All non-durable subscribers are maintained in memory
     * until their endpoint is removed.
     */
    private HashMap _consumers = new HashMap();

    /**
     * The set of all consumer endpoints. This is a map of {@link
     * ConsumerEndpoint} instances, keyed on {@link ConsumerEndpoint#getPersistentId()}
     * if non null; otherwise {@link ConsumerEndpoint#getId()}.
     */
    private HashMap _endpoints = new HashMap();


    /**
     * Maintains a mapping between destinations and consumers. A destination can
     * have more than one consumer and a consumer can also be registered to more
     * than one destination
     */
    private HashMap _destToConsumerMap = new HashMap();

    /**
     * The set of all wildcard consumers, represented by a map of ConsumerEntry
     * -> JmsTopic instances.
     */
    private HashMap _wildcardConsumers = new HashMap();

    /**
     * The seed to allocate identifiers to new consumers.
     */
    private long _consumerIdSeed = 0;

    /**
     * The logger.
     */
    private static final Log _log = LogFactory.getLog(
            ConsumerManagerImpl.class);


    /**
     * Construct a new  <code>ConsumerManager</code>.
     *
     * @param destinations the destination manager
     * @param database     the database service
     */
    public ConsumerManagerImpl(DestinationManager destinations,
                               DatabaseService database) {
        if (destinations == null) {
            throw new IllegalArgumentException(
                    "Argument 'destinations' is null");
        }
        if (database == null) {
            throw new IllegalArgumentException("Argument 'database' is null");
        }
        _destinations = destinations;
        _database = database;
    }

    /**
     * Create a new durable subscription.
     * <p/>
     * A client can change an existing durable subscription by creating a new
     * subscription with the same name and a new topic. Changing a durable
     * subscriber is equivalent to unsubscribing the old one and creating a new
     * one.
     *
     * @param topic    the topic to subscribe to
     * @param name     the subscription name
     * @param clientID the client identifier. May be <code>null</code>
     * @throws InvalidDestinationException if <code>topic</code> is not a
     *                                     persistent destination, or
     *                                     <code>name</code> is an invalid
     *                                     subscription name
     * @throws JMSException                if the durable consumer can't be
     *                                     created
     */
    public synchronized void subscribe(JmsTopic topic, String name,
                                       String clientID)
            throws JMSException {
        createInactiveDurableConsumer(topic, name, clientID);
    }


    /**
     * Remove a durable subscription.
     * <p/>
     * A subscription may only be removed if the associated {@link
     * DurableConsumerEndpoint} is inactive.
     *
     * @param name     the subscription name
     * @param clientID the client identifier. May be <code>null</code>
     * @throws InvalidDestinationException if an invalid subscription name is
     *                                     specified.
     * @throws JMSException                if the durable consumer is active, or
     *                                     cannot be removed
     */
    public synchronized void unsubscribe(String name, String clientID)
            throws JMSException {
        if (_log.isDebugEnabled()) {
            _log.debug("unsubscribe(name=" + name + ", clientID="
                       + clientID + ")");
        }

        DurableConsumerEndpoint consumer
                = (DurableConsumerEndpoint) _endpoints.remove(name);
        if (consumer == null) {
            throw new InvalidDestinationException("Durable consumer " + name
                                                  + " is not defined.");
        }
        if (consumer.isActive()) {
            throw new JMSException("Cannot remove durable consumer=" + name
                                   + ": consumer is active");
        }
        consumer.close();

        // remove it from the persistent store.
        try {
            _database.begin();
            Connection connection = _database.getConnection();

            _database.getAdapter().removeDurableConsumer(connection, name);
            removeConsumerEntry(name);
            _database.commit();
        } catch (PersistenceException exception) {
            String msg = "Failed to remove durable consumer, name=" + name;
            rethrow(msg, exception);
        }
    }

    /**
     * Remove all durable subscriptions for a destination.
     * <p/>
     * Subscriptions may only be removed if the associated {@link
     * ConsumerEndpoint}s are inactive.
     *
     * @param topic the topic to remove consumers for
     * @throws JMSException if the subscriptions can't be removed
     */
    public synchronized void unsubscribe(JmsTopic topic) throws JMSException {
        List list = (List) _destToConsumerMap.get(topic);
        if (list != null) {
            ConsumerEntry[] consumers
                    = (ConsumerEntry[]) list.toArray(new ConsumerEntry[0]);
            for (int i = 0; i < consumers.length; ++i) {
                ConsumerEntry consumer = consumers[i];
                if (consumer.isDurable()) {
                    // remove the durable consumer. This operation
                    // will fail if the consumer is active.
                    unsubscribe(consumer.getName(), consumer.getClientID());
                }
            }
        }

        // remove all consumers for the specified destination
        removeFromConsumerCache(topic);
    }

    /**
     * Create a transient consumer for the specified destination.
     *
     * @param destination  the destination to consume messages from
     * @param connectionId the identity of the connection that owns this
     *                     consumer
     * @param selector     the message selector. May be <code>null</code>
     * @param noLocal      if true, and the destination is a topic, inhibits the
     *                     delivery of messages published by its own connection.
     *                     The behavior for <code>noLocal</code> is not
     *                     specified if the destination is a queue.
     * @return a new transient consumer
     */
    public synchronized ConsumerEndpoint createConsumer(
            JmsDestination destination, long connectionId,
            String selector,
            boolean noLocal)
            throws JMSException, InvalidSelectorException {

        if (_log.isDebugEnabled()) {
            _log.debug("createConsumerEndpoint(destination=" + destination
                       + ", connectionId=" + connectionId
                       + ", selector=" + selector
                       + ", noLocal=" + noLocal + ")");
        }

        ConsumerEndpoint consumer = null;

        // ensure that the destination is valid before proceeding
        getDestination(destination, true);

        long consumerId = getNextConsumerId();

        try {
            _database.begin();
            // determine what type of consumer to create based on the destination
            // it subscribes to.
            if (destination instanceof JmsTopic) {
                JmsTopic topic = (JmsTopic) destination;
                consumer = new TopicConsumerEndpoint(consumerId, connectionId,
                                                     topic, selector, noLocal,
                                                     _destinations);
            } else if (destination instanceof JmsQueue) {
                QueueDestinationCache cache;
                cache = (QueueDestinationCache) _destinations.getDestinationCache(
                        destination);
                consumer = new QueueConsumerEndpoint(consumerId, cache, selector);
            }

            if (consumer != null) {
                // add it to the list of managed consumers. If it has a persistent
                // identity, use that as the key, otherwise use its transient
                // identity.
                Object key = ConsumerEntry.getConsumerKey(consumer);
                _endpoints.put(key, consumer);
                addConsumerEntry(key, destination, null, false);
            }
            _database.commit();
        } catch (Exception exception) {
            rethrow("Failed to create consumer", exception);