org.apache.commons.messagelet
Class BridgeMDO

java.lang.Object
  org.apache.commons.messagelet.MessageDrivenObjectSupport
      org.apache.commons.messagelet.MessengerMDO
          org.apache.commons.messagelet.BridgeMDO

All Implemented Interfaces:

javax.jms.MessageListener, MessageDrivenObject, MessengerListener

Direct Known Subclasses:

DistributeBridgeMDO

public class BridgeMDO
extends MessengerMDO

BridgeMDO is an MDO which implements a JMS bridge from one JMS destination and connection to another. This allows messages to be consumed on one destination and sent to another JMS destination, using possibly different JMS providers. For example this can be used to bridge from SpiritWave to MQSeries.

This class is a useful base class to other possible bridge implementations such as 2 phase commit bridges or bridges with some complex transformation etc. This class has a number of Factory and Strategy methods to further customize the acknowledgement and transaction management, the message construction, transformation and how to handle message headers etc.

Version:

$Revision: 155459 $

Author:

James Strachan

Constructor Summary

BridgeMDO()

Method Summary

protected void	acknowledge(javax.jms.Message message) Strategy method to allow different derived classes to acknowledge messages differently, such as to disable acknowledgements
protected void	commit() Strategy method to perform a commit() on both the incoming Messenger and the output Messenger.
protected javax.jms.BytesMessage	createOutputBytesMessage(javax.jms.BytesMessage inputMessage) Factory method to create BytesMessage Derived classes could override this method to perform any kind of Message transformation.
protected javax.jms.MapMessage	createOutputMapMessage(javax.jms.MapMessage inputMessage) Factory method to create MapMessage Derived classes could override this method to perform any kind of Message transformation.
protected javax.jms.Message	createOutputMessage(javax.jms.Message inputMessage) Factory method to create an output message given an input message.
protected javax.jms.ObjectMessage	createOutputObjectMessage(javax.jms.ObjectMessage inputMessage) Factory method to create ObjectMessage Derived classes could override this method to perform any kind of Message transformation.
protected javax.jms.StreamMessage	createOutputStreamMessage(javax.jms.StreamMessage inputMessage) Factory method to create StreamMessage Derived classes could override this method to perform any kind of Message transformation.
protected javax.jms.TextMessage	createOutputTextMessage(javax.jms.TextMessage inputMessage) Factory method to create TextMessage Derived classes could override this method to perform any kind of Message transformation.
int	getBufferSize() Gets the buffer size used for ByteMessage and StreamMessage copying
String	getOutputConnection()
javax.jms.Destination	getOutputDestination() Gets the Destination output messages will be sent to
Messenger	getOutputMessenger() Gets the Messenger used to output messages
String	getOutputSubject()
void	init() This method allows the init() method to be overriden without having to call the super.init( ServletContext ) method first.
boolean	isTransacted()
void	onMessage(javax.jms.Message message)
protected void	processMessageHeaders(javax.jms.Message inputMessage, javax.jms.Message outputMessage) Strategy method to add any headers required on the output message.
protected void	rollback() Strategy method to perform a rollback() on both the incoming Messenger and the output Messenger.
void	setBufferSize(int bufferSize) Sets the buffer size used for ByteMessage and StreamMessage copying
void	setOutputConnection(String outputConnection) Sets the connection name (messenger instance) to use to output messages
void	setOutputDestination(javax.jms.Destination outputDestination) Sets the Destination output messages will be sent to
void	setOutputMessenger(Messenger outputMessenger) Sets the Messenger used to output messages
void	setOutputSubject(String outputSubject) Sets the subject (i.e.
void	setTransacted(boolean transacted) Sets whether this MDO should work in transacted mode
protected void	validateOutputDestination() Validates that there is a valid output destintation that we can use.

Methods inherited from class org.apache.commons.messagelet.MessengerMDO

getMessenger, getMessengerManager, setMessenger, setMessengerManager

Methods inherited from class org.apache.commons.messagelet.MessageDrivenObjectSupport

destroy, getLog, getServletContext, init, log, log

Methods inherited from class java.lang.Object

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

Constructor Detail

BridgeMDO

public BridgeMDO()

Method Detail

init

public void init()
          throws javax.servlet.ServletException

Description copied from class: MessageDrivenObjectSupport

This method allows the init() method to be overriden without having to call the super.init( ServletContext ) method first. This is similar to the init() method in GenericServlet.

Overrides:

init in class MessageDrivenObjectSupport

Throws:

javax.servlet.ServletException

onMessage

public void onMessage(javax.jms.Message message)

isTransacted

public boolean isTransacted()

Returns:

true if this MDO should work in transacted mode

setTransacted

public void setTransacted(boolean transacted)

Sets whether this MDO should work in transacted mode

getOutputConnection

public String getOutputConnection()

setOutputConnection

public void setOutputConnection(String outputConnection)

Sets the connection name (messenger instance) to use to output messages

getOutputSubject

public String getOutputSubject()

setOutputSubject

public void setOutputSubject(String outputSubject)

Sets the subject (i.e. destination name) to send messages to

getOutputMessenger

public Messenger getOutputMessenger()
                             throws javax.jms.JMSException

Gets the Messenger used to output messages

Throws:

javax.jms.JMSException

setOutputMessenger

public void setOutputMessenger(Messenger outputMessenger)

Sets the Messenger used to output messages

getOutputDestination

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

Gets the Destination output messages will be sent to

Throws:

javax.jms.JMSException

setOutputDestination

public void setOutputDestination(javax.jms.Destination outputDestination)

Sets the Destination output messages will be sent to

getBufferSize

public int getBufferSize()

Gets the buffer size used for ByteMessage and StreamMessage copying

setBufferSize

public void setBufferSize(int bufferSize)

Sets the buffer size used for ByteMessage and StreamMessage copying

commit

protected void commit()
               throws javax.jms.JMSException

Strategy method to perform a commit() on both the incoming Messenger and the output Messenger.

Throws:

javax.jms.JMSException

rollback

protected void rollback()

Strategy method to perform a rollback() on both the incoming Messenger and the output Messenger.

createOutputMessage

protected javax.jms.Message createOutputMessage(javax.jms.Message inputMessage)
                                         throws javax.jms.JMSException

Factory method to create an output message given an input message. Derived classes could override this method to perform any kind of Message transformation.

Throws:

javax.jms.JMSException

createOutputObjectMessage

protected javax.jms.ObjectMessage createOutputObjectMessage(javax.jms.ObjectMessage inputMessage)
                                                     throws javax.jms.JMSException

Factory method to create ObjectMessage Derived classes could override this method to perform any kind of Message transformation.

Throws:

javax.jms.JMSException

createOutputTextMessage

protected javax.jms.TextMessage createOutputTextMessage(javax.jms.TextMessage inputMessage)
                                                 throws javax.jms.JMSException

Factory method to create TextMessage Derived classes could override this method to perform any kind of Message transformation.

Throws:

javax.jms.JMSException

createOutputMapMessage

protected javax.jms.MapMessage createOutputMapMessage(javax.jms.MapMessage inputMessage)
                                               throws javax.jms.JMSException

Factory method to create MapMessage Derived classes could override this method to perform any kind of Message transformation.

Throws:

javax.jms.JMSException

createOutputBytesMessage

protected javax.jms.BytesMessage createOutputBytesMessage(javax.jms.BytesMessage inputMessage)
                                                   throws javax.jms.JMSException

Factory method to create BytesMessage Derived classes could override this method to perform any kind of Message transformation.

Throws:

javax.jms.JMSException

createOutputStreamMessage

protected javax.jms.StreamMessage createOutputStreamMessage(javax.jms.StreamMessage inputMessage)
                                                     throws javax.jms.JMSException

Factory method to create StreamMessage Derived classes could override this method to perform any kind of Message transformation.

Throws:

javax.jms.JMSException

processMessageHeaders

protected void processMessageHeaders(javax.jms.Message inputMessage,
                                     javax.jms.Message outputMessage)
                              throws javax.jms.JMSException

Strategy method to add any headers required on the output message. Derived classes could override this method to perform any kind of header processing, such as copying the correlation ID, copying all headers or adding some new custom headers etc.

Throws:

javax.jms.JMSException

acknowledge

protected void acknowledge(javax.jms.Message message)
                    throws javax.jms.JMSException

Strategy method to allow different derived classes to acknowledge messages differently, such as to disable acknowledgements

Throws:

javax.jms.JMSException

validateOutputDestination

protected void validateOutputDestination()
                                  throws javax.jms.JMSException,
                                         javax.servlet.ServletException

Validates that there is a valid output destintation that we can use. Derivations of this class could use multiple destinations

Throws:

javax.jms.JMSException

javax.servlet.ServletException