org.apache.cayenne.event
Class JMSBridge

java.lang.Object
  org.apache.cayenne.event.EventBridge
      org.apache.cayenne.event.JMSBridge

All Implemented Interfaces:

EventListener, javax.jms.MessageListener

public class JMSBridge
extends EventBridge
implements javax.jms.MessageListener

Implementation of EventBridge that passes and receives events via JMS (Java Messaging Service). JMSBridge uses "publish/subscribe" model for communication with external agents.

Since:

1.1

Field Summary

protected javax.jms.TopicPublisher	publisher
protected javax.jms.TopicConnection	receivedConnection
protected javax.jms.TopicConnection	sendConnection
protected javax.jms.TopicSession	sendSession
protected javax.jms.TopicSubscriber	subscriber
protected String	topicConnectionFactoryName

Fields inherited from class org.apache.cayenne.event.EventBridge

eventManager, externalEventSource, externalSubject, localSubjects, mode, RECEIVE_EXTERNAL, RECEIVE_LOCAL, RECEIVE_LOCAL_EXTERNAL

Constructor Summary

JMSBridge(Collection<EventSubject> localSubjects, String externalSubject)

JMSBridge(EventSubject localSubject, String externalSubject)

Method Summary

protected Serializable	eventToMessageObject(CayenneEvent event) Converts CayenneEvent to a serializable object that will be sent via JMS.
String	getTopicConnectionFactoryName()
protected CayenneEvent	messageObjectToEvent(Serializable object) Converts a Serializable instance to CayenneEvent.
void	onMessage(javax.jms.Message message) JMS MessageListener implementation.
protected void	sendExternalEvent(CayenneEvent localEvent) Sends a Cayenne event over the transport supported by this bridge.
void	setTopicConnectionFactoryName(String name)
protected void	shutdownExternal() Closes all resources used to communicate via JMS.
protected void	startupExternal() Starts up JMS machinery for "publish/subscribe" model.
protected javax.jms.Topic	topicNotFound(Context jndiContext, NamingException ex) Attempts to create missing Topic.

Methods inherited from class org.apache.cayenne.event.EventBridge

convertToExternalSubject, getEventManager, getExternalEventSource, getExternalSubject, getLocalSubjects, isRunning, onExternalEvent, receivesExternalEvents, receivesLocalEvents, shutdown, startup, startup, startup

Methods inherited from class java.lang.Object

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

Field Detail

topicConnectionFactoryName

protected String topicConnectionFactoryName

sendConnection

protected javax.jms.TopicConnection sendConnection

sendSession

protected javax.jms.TopicSession sendSession

receivedConnection

protected javax.jms.TopicConnection receivedConnection

publisher

protected javax.jms.TopicPublisher publisher

subscriber

protected javax.jms.TopicSubscriber subscriber

Constructor Detail

JMSBridge

public JMSBridge(EventSubject localSubject,
                 String externalSubject)

JMSBridge

public JMSBridge(Collection<EventSubject> localSubjects,
                 String externalSubject)

Since:

1.2

Method Detail

onMessage

public void onMessage(javax.jms.Message message)

JMS MessageListener implementation. Injects received events to the EventManager local event queue.

Specified by:

onMessage in interface javax.jms.MessageListener

getTopicConnectionFactoryName

public String getTopicConnectionFactoryName()

Returns:

Name of javax.jms.TopicConnectionFactory accessible via JNDI.

setTopicConnectionFactoryName

public void setTopicConnectionFactoryName(String name)

startupExternal

protected void startupExternal()
                        throws Exception

Starts up JMS machinery for "publish/subscribe" model.

Specified by:

startupExternal in class EventBridge

Throws:

Exception

topicNotFound

protected javax.jms.Topic topicNotFound(Context jndiContext,
                                        NamingException ex)
                                 throws Exception

Attempts to create missing Topic. Since Topic creation is JMS-implementation specific, this task is left to subclasses. Current implementation simply rethrows the exception.

Throws:

Exception

shutdownExternal

protected void shutdownExternal()
                         throws Exception

Closes all resources used to communicate via JMS.

Specified by:

shutdownExternal in class EventBridge

Throws:

Exception

sendExternalEvent

protected void sendExternalEvent(CayenneEvent localEvent)
                          throws Exception

Description copied from class: EventBridge

Sends a Cayenne event over the transport supported by this bridge.

Specified by:

sendExternalEvent in class EventBridge

Throws:

Exception

eventToMessageObject

protected Serializable eventToMessageObject(CayenneEvent event)
                                     throws Exception

Converts CayenneEvent to a serializable object that will be sent via JMS. Default implementation simply returns the event, but subclasses can customize this behavior.

Throws:

Exception

messageObjectToEvent

protected CayenneEvent messageObjectToEvent(Serializable object)
                                     throws Exception

Converts a Serializable instance to CayenneEvent. Returns null if the object is not supported. Default implementation simply tries to cast the object to CayenneEvent, but subclasses can customize this behavior.

Throws:

Exception