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Greg,
Only
Topic is multicast by specification. To keep all objects on the network
updated, simply have any object that is subject to caching to publish the
appropriate change-Topic message and those that are interested in the change
subscribe to that change-Topic. There is basically two ways to propagate the
change: 1) use a text message containing the database reference id so that the
correct row can be refetched (IO expense) or 2) use an object message containing
a DataObjectChangeEvent object with the old and new values so that the
subscriber can determine which of its values change by check the old value (no
IO expense). Remember all object of a class will be subscribers to the
change message, which means that a subscriber must be able to determine readily
(simply) whether the received message needs to be processed or
not.
Dave
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