com.j_spaces.jms

Class GSMessageConsumerImpl

java.lang.Object

com.j_spaces.jms.GSMessageConsumerImpl

All Implemented Interfaces:

javax.jms.MessageConsumer, javax.jms.QueueReceiver, javax.jms.TopicSubscriber

Direct Known Subclasses:

GSQueueReceiverImpl, GSTopicSubscriberImpl

public class GSMessageConsumerImpl
extends Object
implements javax.jms.MessageConsumer, javax.jms.QueueReceiver, javax.jms.TopicSubscriber

Implements the javax.jms.MessageConsumer interface. GigaSpaces implementation of the JMS MessageConsumer Interface and the Jini RemoteEventListener.

 - It holds MessageConsumer Destination, Topic or Queue
 - It creates the GigaSpaces OnMessageNotifyDelegator and the notify() calls
 the MessageListener.onMessage() method.
 - It supports both Synchronized and Asynchronized message consumption.
 One can use the method receive() for the Synchronized form,
 or use the NotifyDelegator together with a MessageListener
 implementation for the Asynchronized message receiving manner.

 

Version:

4.0 Copyright: Copyright (c) 2004 Company: GigaSpaces Technologies,Ltd.

Author:

Gershon Diner

Field Summary

Fields

Modifier and Type	Field and Description
protected boolean	m_closed true if the session is closed.
protected javax.jms.Destination	m_dest The destination the consumer gets its messages from
protected String	m_destName The destination name the consumer gets its messages from GERSHON FIX 25042006 - The default class name (dest name is dummy in case the destination is null in the beginning and that later passed to the send().
String	m_durableSubscriptionName The durable consumer subscription name.
protected boolean	m_isQueue Tells whether this is a queue or a topic consumer
protected GSSessionImpl	m_session The m_session the consumer belongs to

Constructor Summary

Constructors

Constructor and Description
GSMessageConsumerImpl(GSSessionImpl session, javax.jms.Destination dest, String consumerID, String subsriptionName, String selector, boolean noLocal) Constructs a message consumer.

Method Summary

Modifier and Type	Method and Description
void	close() Cancels the onMessage notify delegator, using its Lease.cancel() if it is an Asyc operation Also it removes the current consumer from the consumers list held by the session.
String	getConsumerID() Returns the consumer ID.
javax.jms.Destination	getDestination()
javax.jms.MessageListener	getMessageListener() API method.
String	getMessageSelector() API method.
String	getName() Return the durable subscription name
boolean	getNoLocal()
javax.jms.Queue	getQueue()
protected GSSessionImpl	getSession() Returns the m_session that created this consumer.
javax.jms.Topic	getTopic()
boolean	isClosed() Determines if the consumer is closed
boolean	isDurableSubscriber() Determines if the subscriber is durable
javax.jms.Message	receive() API method.
javax.jms.Message	receive(long timeout) API method.
javax.jms.Message	receiveNoWait() API method.
void	setMessageListener(javax.jms.MessageListener listener) This method is called by the JMS Client, it sets the MessageListener implementation and It creates a GigaSpaces NotifyDelegator for Asynchronic messaging.
String	toString()

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

m_dest

protected javax.jms.Destination m_dest

The destination the consumer gets its messages from

m_destName

protected String m_destName

The destination name the consumer gets its messages from GERSHON FIX 25042006 - The default class name (dest name is dummy in case the destination is null in the beginning and that later passed to the send(). We then set the extEntry className using the destName

m_session

protected GSSessionImpl m_session

The m_session the consumer belongs to

m_isQueue

protected volatile boolean m_isQueue

Tells whether this is a queue or a topic consumer

m_closed

protected volatile boolean m_closed

true if the session is closed.

m_durableSubscriptionName

public String m_durableSubscriptionName

The durable consumer subscription name.

Constructor Detail

GSMessageConsumerImpl

public GSMessageConsumerImpl(GSSessionImpl session,
                             javax.jms.Destination dest,
                             String consumerID,
                             String subsriptionName,
                             String selector,
                             boolean noLocal)
                      throws javax.jms.JMSException

Constructs a message consumer.

Parameters:

session - The m_session the consumer belongs to.

dest - The destination the consumer gets messages from.

subsriptionName - The m_durableSubscriber subscription's name, if any.

selector - Selector string for filtering messages.

Throws:

javax.jms.IllegalStateException - If the connection is broken.

javax.jms.JMSException - If the creation fails for any other reason.

Method Detail

getMessageSelector

public String getMessageSelector()
                          throws javax.jms.JMSException

API method.

Specified by:

getMessageSelector in interface javax.jms.MessageConsumer

Throws:

javax.jms.IllegalStateException - If the consumer is closed.

javax.jms.JMSException

getMessageListener

public javax.jms.MessageListener getMessageListener()
                                             throws javax.jms.JMSException

API method.

Specified by:

getMessageListener in interface javax.jms.MessageConsumer

Returns:

m_messageListener

Throws:

javax.jms.IllegalStateException - If the consumer is closed.

javax.jms.JMSException

setMessageListener

public void setMessageListener(javax.jms.MessageListener listener)
                        throws javax.jms.JMSException

This method is called by the JMS Client, it sets the MessageListener implementation and It creates a GigaSpaces NotifyDelegator for Asynchronic messaging. It also supports the case of a Durable Subscriber, in which accumulated messages in the GigaSpaces space while it was not up and listening. It performs a m_space.readMultiple() which gets all the pending entries, it calls then the MessageListener.onMessage(), same as the notify() does, but it also keeps the entries in the pendingEntriesHash so the notify() will check and wont execute duplicated entries. This method must NOT be called if the connection the consumer belongs to is started, because the session would then be accessed by the thread calling this method and by the thread controlling asynchronous deliveries. This situation is clearly forbidden by the single threaded nature of sessions. Moreover, unsetting a message listener without stopping the connection may lead to the situation where asynchronous deliveries would arrive on the connection, the session or the consumer without being able to reach their target listener!

Specified by:

setMessageListener in interface javax.jms.MessageConsumer

Throws:

javax.jms.IllegalStateException - If the consumer is closed.

javax.jms.JMSException

See Also:

MessageConsumer.setMessageListener(MessageListener)

receive

public javax.jms.Message receive()
                          throws javax.jms.JMSException

API method. Using default readTimeout which is Long.MAX_VALUE. This call blocks until a message arrives, the timeout expires, or this message consumer is m_closed.

Specified by:

receive in interface javax.jms.MessageConsumer

Throws:

javax.jms.IllegalStateException - If the consumer is closed, or if the connection is broken.

javax.jms.JMSSecurityException - If the requester is not a READER on the destination.

javax.jms.JMSException - If the request fails for any other reason.

receive

public javax.jms.Message receive(long timeout)
                          throws javax.jms.JMSException

API method. It is a Synch receive implementation which reads ExternalEntry from space, then it checks if the ExternalEntry is still valid and did not expired. In case of a CLIENT_ACK then we prepare a JMSAckDataEntry to be later written to space, otherwise (if ACK is not necessary) if it is a Queue, we perform a space.clear() operation, which clears the entry from space, but if it is a Topic we leave it as is.

Specified by:

receive in interface javax.jms.MessageConsumer

Parameters:

timeout - This call blocks until a message arrives, the timeout expires, or this message consumer is closed. The jms client may select A timeout of zero, that means it never expires, and the call blocks indefinitely. It is the same as the Space timeout which its value to Long.MAX_VALUE Regarding the space timeout, it means how long the client is willing to wait for a transactionally proper matching entry. A timeout of IJSpace.NO_WAIT means to wait no time at all; this is equivalent to a wait of zero (in space only, not in jms).

Throws:

javax.jms.IllegalStateException - If the consumer is closed, or if the connection is broken.

javax.jms.JMSSecurityException - If the requester is not a READER on the destination.

javax.jms.JMSException - If the request fails for any other reason.

receiveNoWait

public javax.jms.Message receiveNoWait()
                                throws javax.jms.JMSException

API method.

Specified by:

receiveNoWait in interface javax.jms.MessageConsumer

Throws:

javax.jms.IllegalStateException - If the consumer is closed, or if the connection is broken.

javax.jms.JMSSecurityException - If the requester is not a READER on the destination.

javax.jms.JMSException - If the request fails for any other reason.

isClosed

public boolean isClosed()

Determines if the consumer is closed

Returns:

true if the consumer is closed

close

public void close()
           throws javax.jms.JMSException

Cancels the onMessage notify delegator, using its Lease.cancel() if it is an Asyc operation Also it removes the current consumer from the consumers list held by the session.

Specified by:

close in interface javax.jms.MessageConsumer

Throws:

javax.jms.JMSException

See Also:

MessageConsumer.close()

toString

public String toString()

Overrides:

toString in class Object

getConsumerID

public String getConsumerID()

Returns the consumer ID.

Returns:

The consumer ID

getSession

protected GSSessionImpl getSession()

Returns the m_session that created this consumer. It might be a GSTopicSessionImpl or GSQueueSessionImpl

Returns:

the m_session that created this consumer

getName

public String getName()

Return the durable subscription name

Returns:

the durable subscription name, or null if this is a non-durable subscriber

isDurableSubscriber

public boolean isDurableSubscriber()

Determines if the subscriber is durable

Returns:

true if the subscriber is durable

getQueue

public javax.jms.Queue getQueue()
                         throws javax.jms.JMSException

Specified by:

getQueue in interface javax.jms.QueueReceiver

Throws:

javax.jms.JMSException

See Also:

QueueReceiver.getQueue()

getNoLocal

public boolean getNoLocal()
                   throws javax.jms.JMSException

Specified by:

getNoLocal in interface javax.jms.TopicSubscriber

Throws:

javax.jms.JMSException

See Also:

TopicSubscriber.getNoLocal()

getTopic

public javax.jms.Topic getTopic()
                         throws javax.jms.JMSException

Specified by:

getTopic in interface javax.jms.TopicSubscriber

Throws:

javax.jms.JMSException

See Also:

TopicSubscriber.getTopic()

getDestination

public javax.jms.Destination getDestination()
                                     throws javax.jms.JMSException

Throws:

javax.jms.JMSException