org.xmlBlaster.contrib
Interface I_ChangePublisher

All Superinterfaces:

java.util.EventListener, I_ContribPlugin

All Known Implementing Classes:

MomEventEngine, SqlInfoStreamPublisher, TestDbBasics, TestDbSpecific, TestSyncPart, XmlBlasterPublisher

public interface I_ChangePublisher
extends java.util.EventListener, I_ContribPlugin

Interface to hide the publisher destination.

A typical plugin publishes the changes to xmlBlaster MoM but could be any other data sink like JMS or file system as well.

Author:

Marcel Ruff

Method Summary

XBSession	getJmsSession() Only used in replication, can return null if not used.
void	init(I_Info info) After creation this method is called.
java.lang.String	publish(java.lang.String changeKey, byte[] message, java.util.Map attrMap) Send the message to the MoM.
boolean	registerAlertListener(I_Update update, java.util.Map attrs) Register for alerts when the data source has changed.
void	shutdown() Cleanup resources.

Methods inherited from interface org.xmlBlaster.contrib.I_ContribPlugin

getUsedPropertyKeys

Method Detail

init

void init(I_Info info)
          throws java.lang.Exception

After creation this method is called. The plugin must register itself into global scope with info.setObject("org.xmlBlaster.contrib.dbwatcher.mom.I_ChangePublisher", this) to be available for others.

Specified by:

init in interface I_ContribPlugin

Parameters:

info - The configuration environment

Throws:

java.lang.Exception - MoM specific

publish

java.lang.String publish(java.lang.String changeKey,
                         byte[] message,
                         java.util.Map attrMap)
                         throws java.lang.Exception

Send the message to the MoM.

Parameters:

changeKey - Can be used to create the topic name

message - The message content to send

attrMap - An optional map with attributes or null

Returns:

A unique identifier of the sent message

Throws:

java.lang.Exception - On sending problems

registerAlertListener

boolean registerAlertListener(I_Update update,
                              java.util.Map attrs)
                              throws java.lang.Exception

Register for alerts when the data source has changed.

This funtionality is plugin depending, for example the xmlBlaster plugin has a configuration option to subscribe on a alert topic and listens if somebody publishes a message to it. If such a message arrives we trigger a new database poll.

Parameters:

update - The callback interface to receive the notification

attrs - extra parameters to pass for the registration. For example if one implementation wants to do a specific extra subscription it would pass the quality of service in the attributes.

Returns:

true if a notification is available (is configured)

Throws:

java.lang.Exception - The MoM specific exception

shutdown

void shutdown()

Cleanup resources.

Can be called multiple times if instance is reused from different plugins.

Specified by:

shutdown in interface I_ContribPlugin

See Also:

I_Plugin

getJmsSession

XBSession getJmsSession()

Only used in replication, can return null if not used.

Returns: