From: "Jeremy Boynes" <[EMAIL PROTECTED]>
Date: Sat, 4 Oct 2003 00:50:19 -0700

MBean persistence is used to store the configuration of each MBean (the
values of persistent attributes). This is used to reload the MBeans on
restart. The JSR77 state is not a persistent attribute, so all MBeans
come back in the STOPPED state.
I see. So the "Persistence Service" snapshots the persistent attribute of an MBean. And the "Service Controler" snapshots the transient attributes, which are specific to the MBean state?

What I had in mind was to add a persistent attribute to AbstractManagedObject abstracting the target state to reach when the server is restarted. This persistent attribute mirrors the transient state attribute and is persisted based on the installed persistence policy (which could be checkpoint, on attribute change et cetera). The mirroring of the transient state and the target state is broken when a request to shutdown the server is received.

When a ManagedObject is restored, one uses this target state to trigger the relevant operation. One drawback I see in defining two services is that we will end up with two locations to be merged when the server is re-started. Moreover, it allows to share the persistence policy between these two services.

Given child objects can be stopped, I doubt startRecursive is the way to
go - instead, the controller will need to start each one individually
(and in the correct order).
startRecursive is not the way to go to restore the identical state. However it will be the more simple to implement.

Indeed, as you have underlined the controller will need to start in the right order the services. To start in the right order these services, this controller will need to re-implement a significant part of the DependencyService. I agree that the canStart method is a good template to implement such a feature. This is an academic exercice and also quite time consuming.

Gianny

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