abstractmessagelistenercontainer.java

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/*
 * Copyright 2002-2006 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.jms.listener;

import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;

import javax.jms.Connection;
import javax.jms.Destination;
import javax.jms.ExceptionListener;
import javax.jms.JMSException;
import javax.jms.Message;
import javax.jms.MessageListener;
import javax.jms.Session;
import javax.jms.Topic;

import org.springframework.beans.factory.DisposableBean;
import org.springframework.context.Lifecycle;
import org.springframework.jms.JmsException;
import org.springframework.jms.support.JmsUtils;
import org.springframework.jms.support.destination.JmsDestinationAccessor;
import org.springframework.util.Assert;
import org.springframework.util.ClassUtils;

/**
 * Abstract base class for message listener containers. Can either host
 * a standard JMS {@link MessageListener} or a Spring-specific
 * {@link SessionAwareMessageListener}.
 *
 * <p>Usually holds a single JMS {@link Connection} that all listeners are
 * supposed to be registered on, which is the standard JMS way of managing
 * listeners. Can alternatively also be used with a fresh Connection per
 * listener, for J2EE-style XA-aware JMS messaging. The actual registration
 * process is up to concrete subclasses.
 *
 * <p><b>NOTE:</b> The default behavior of this message listener container
 * is to <b>never</b> propagate an exception thrown by a message listener up to
 * the JMS provider. Instead, it will log any such exception at the error level.
 * This means that from the perspective of the attendant JMS provider no such
 * listener will ever fail.
 *
 * <p>The listener container offers the following message acknowledgment options:
 * <ul>
 * <li>"sessionAcknowledgeMode" set to "AUTO_ACKNOWLEDGE" (default):
 * Automatic message acknowledgment <i>before</i> listener execution;
 * no redelivery in case of exception thrown.
 * <li>"sessionAcknowledgeMode" set to "CLIENT_ACKNOWLEDGE":
 * Automatic message acknowledgment <i>after</i> successful listener execution;
 * no redelivery in case of exception thrown.
 * <li>"sessionAcknowledgeMode" set to "DUPS_OK_ACKNOWLEDGE":
 * <i>Lazy</i> message acknowledgment during or after listener execution;
 * <i>potential redelivery</i> in case of exception thrown.
 * <li>"sessionTransacted" set to "true":
 * Transactional acknowledgment after successful listener execution;
 * <i>guaranteed redelivery</i> in case of exception thrown.
 * </ul>
 * The exact behavior might vary according to the concrete listener container
 * and JMS provider used.
 *
 * <p>Note that there is a corner case when using "sessionTransacted",
 * where the listener might have returned successfully but the server
 * died before acknowledging the message. As a consequence, a message
 * <i>might get redelivered even after successful processing</i> -
 * potentially leading to duplicate processing of the message.
 * This violates "exactly-once" semantics, at least potentially.
 *
 * <p>There are two solutions to the duplicate processing problem:
 * <ul>
 * <li>Either add <i>duplicate message detection</i> to your listener, in the
 * form of a business entity existence check or a protocol table check. This
 * usually just needs to be done in case of the JMSRedelivered flag being
 * set on the incoming message (else just process straightforwardly).
 * <li>Or wrap the <i>entire processing with an XA transaction</i>, covering the
 * reception of the message as well as the execution of the message listener.
 * This is only supported by {@link DefaultMessageListenerContainer}, through
 * specifying a "transactionManager" (typically a
 * {@link org.springframework.transaction.jta.JtaTransactionManager}, with
 * a corresponding XA-aware JMS {@link javax.jms.ConnectionFactory} passed in as
 * "connectionFactory").
 * </ul>
 * Note that XA transaction coordination adds significant runtime overhead,
 * so it might be feasible to avoid it unless absolutely necessary.
 *
 * <p><b>Recommendations:</b>
 * <ul>
 * <li>The general recommendation is to set "sessionTransacted" to "true",
 * typically in combination with local database transactions triggered by the
 * listener implementation, through Spring's standard transaction facilities.
 * This will work nicely in Tomcat or in a standalone environment, often
 * combined with custom duplicate message detection (if it is unacceptable
 * to ever process the same message twice).
 * <li>Alternatively, specify a
 * {@link org.springframework.transaction.jta.JtaTransactionManager} as "transactionManager"
 * for a full XA-aware JMS provider - typically when running on a J2EE server,
 * but also for other environments with a JTA transaction manager present.
 * This will give full "exactly-once" guarantees without custom duplicate
 * message checks, at the price of additional runtime processing overhead.
 * </ul>
 *
 * @author Juergen Hoeller
 * @since 2.0
 * @see #setMessageListener
 * @see javax.jms.MessageListener
 * @see SessionAwareMessageListener
 * @see #handleListenerException
 * @see DefaultMessageListenerContainer
 * @see SimpleMessageListenerContainer
 * @see org.springframework.jms.listener.serversession.ServerSessionMessageListenerContainer
 */
public abstract class AbstractMessageListenerContainer extends JmsDestinationAccessor
		implements DisposableBean, Lifecycle {

	private String clientId;

	private Object destination;

	private String messageSelector;

	private Object messageListener;

	private boolean subscriptionDurable = false;

	private String durableSubscriptionName;

	private ExceptionListener exceptionListener;

	private boolean exposeListenerSession = true;

	private boolean autoStartup = true;

	private Connection sharedConnection;

	private final Object sharedConnectionMonitor = new Object();

	private volatile boolean active = false;

	private boolean running = false;

	private final List pausedTasks = new LinkedList();

	private final Object lifecycleMonitor = new Object();


	/**
	 * Specify a JMS client id for a shared Connection created and used
	 * by this messager listener container.
	 * <p>Note that client ids need to be unique among all active Connections
	 * of the underlying JMS provider. Furthermore, a client id can only be
	 * assigned if the original ConnectionFactory hasn't already assigned one.
	 * @see javax.jms.Connection#setClientID
	 * @see #setConnectionFactory
	 */
	public void setClientId(String clientId) {
		this.clientId = clientId;
	}

	/**
	 * Return the JMS client ID for the shared Connection created and used
	 * by this messager listener container, if any.
	 */
	protected String getClientId() {
		return clientId;
	}

	/**
	 * Set the destination to receive messages from.
	 * <p>Alternatively, specify a "destinationName", to be dynamically
	 * resolved via the {@link org.springframework.jms.support.destination.DestinationResolver}.
	 * @see #setDestinationName(String)
	 */
	public void setDestination(Destination destination) {
		Assert.notNull(destination, "destination must not be null");
		this.destination = destination;
		setPubSubDomain(destination instanceof Topic);
	}

	/**
	 * Return the destination to receive messages from.
	 * @return the destination to receive messages from (will be
	 * <code>null</code> if the configured destination is not an actual
	 * {@link Destination} type; c.f. {@link #setDestinationName(String)
	 * when the destination is a String})
	 */
	protected Destination getDestination() {
		return (this.destination instanceof Destination ? (Destination) this.destination : null);
	}

	/**
	 * Set the name of the destination to receive messages from.
	 * <p>The specified name will be dynamically resolved via the configured
	 * {@link #setDestinationResolver(org.springframework.jms.support.destination.DestinationResolver) destination resolver}.
	 * <p>Alternatively, specify a JMS {@link Destination} object as "destination".
	 * @param destinationName the desired destination (can be <code>null</code>)
	 * @see #setDestination(javax.jms.Destination)
	 */
	public void setDestinationName(String destinationName) {
		Assert.notNull(destinationName, "destinationName must not be null");
		this.destination = destinationName;
	}

	/**
	 * Return the name of the destination to receive messages from.
	 * @return the name of the destination to receive messages from
	 * (will be <code>null</code> if the configured destination is not a
	 * {@link String} type; c.f. {@link #setDestination(Destination) when
	 * it is an actual Destination})
	 */
	protected String getDestinationName() {
		return (this.destination instanceof String ? (String) this.destination : null);
	}

	/**
	 * Set the JMS message selector expression (or <code>null</code> if none).
	 * Default is none.
	 * <p>See the JMS specification for a detailed definition of selector expressions.
	 */
	public void setMessageSelector(String messageSelector) {
		this.messageSelector = messageSelector;
	}

	/**
	 * Return the JMS message selector expression (or <code>null</code> if none).
	 */
	protected String getMessageSelector() {
		return messageSelector;
	}


	/**
	 * Set the message listener implementation to register.
	 * This can be either a standard JMS {@link MessageListener} object
	 * or a Spring {@link SessionAwareMessageListener} object.
	 * @throws IllegalArgumentException if the supplied listener is not a
	 * {@link MessageListener} or a {@link SessionAwareMessageListener}
	 * @see javax.jms.MessageListener
	 * @see SessionAwareMessageListener
	 */
	public void setMessageListener(Object messageListener) {
		checkMessageListener(messageListener);
		this.messageListener = messageListener;
		if (this.durableSubscriptionName == null) {
			// Use message listener class name as default name for a durable subscription.
			this.durableSubscriptionName = messageListener.getClass().getName();
		}
	}

	/**
	 * Check the given message listener, throwing an exception
	 * if it does not correspond to a supported listener type.
	 * <p>By default, only a standard JMS {@link MessageListener} object or a
	 * Spring {@link SessionAwareMessageListener} object will be accepted.
	 * @param messageListener the message listener object to check
	 * @throws IllegalArgumentException if the supplied listener is not a
	 * {@link MessageListener} or a {@link SessionAwareMessageListener}
	 * @see javax.jms.MessageListener
	 * @see SessionAwareMessageListener
	 */
	protected void checkMessageListener(Object messageListener) {
		if (!(messageListener instanceof MessageListener ||
				messageListener instanceof SessionAwareMessageListener)) {
			throw new IllegalArgumentException(
					"messageListener needs to be of type [" + MessageListener.class.getName() +
					"] or [" + SessionAwareMessageListener.class.getName() + "]");
		}
	}

	/**
	 * Return the message listener object to register.
	 */
	protected Object getMessageListener() {
		return messageListener;
	}

	/**
	 * Set whether to make the subscription durable. The durable subscription name
	 * to be used can be specified through the "durableSubscriptionName" property.
	 * <p>Default is "false". Set this to "true" to register a durable subscription,
	 * typically in combination with a "durableSubscriptionName" value (unless
	 * your message listener class name is good enough as subscription name).
	 * <p>Only makes sense when listening to a topic (pub-sub domain).
	 * @see #setDurableSubscriptionName
	 */
	public void setSubscriptionDurable(boolean subscriptionDurable) {
		this.subscriptionDurable = subscriptionDurable;
	}

	/**
	 * Return whether to make the subscription durable.
	 */
	protected boolean isSubscriptionDurable() {
		return subscriptionDurable;
	}

	/**
	 * Set the name of a durable subscription to create. To be applied in case
	 * of a topic (pub-sub domain) with subscription durability activated.
	 * <p>The durable subscription name needs to be unique within this client's
	 * JMS client id. Default is the class name of the specified message listener.
	 * <p>Note: Only 1 concurrent consumer (which is the default of this
	 * message listener container) is allowed for each durable subscription.
	 * @see #setSubscriptionDurable
	 * @see #setClientId
	 * @see #setMessageListener
	 */
	public void setDurableSubscriptionName(String durableSubscriptionName) {
		Assert.notNull(durableSubscriptionName, "durableSubscriptionName must not be null");
		this.durableSubscriptionName = durableSubscriptionName;
	}

	/**
	 * Return the name of a durable subscription to create, if any.
	 */
	protected String getDurableSubscriptionName() {
		return durableSubscriptionName;
	}

	/**
	 * Set the JMS ExceptionListener to notify in case of a JMSException thrown
	 * by the registered message listener or the invocation infrastructure.
	 */
	public void setExceptionListener(ExceptionListener exceptionListener) {
		this.exceptionListener = exceptionListener;
	}

	/**
	 * Return the JMS ExceptionListener to notify in case of a JMSException thrown
	 * by the registered message listener or the invocation infrastructure, if any.
	 */