Skip to main content

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index] [List Home]
Re: [ecf-dev] Problem with SharedObject API

Hello All,

Scott, thanks for you reply. It works fine.
I had understood SharedObject API and blogged about it (on Russian).

Scott Lewis пишет:
> Hi Pavel,
> Samolisov Pavel wrote:
>> Hash: SHA1
>> Thanks Scott.
>> Tests works fine, my code works too. But I do not understand why this
>> code is in TestSharedObject (in method initialize()):
>> // This is a replica, so initialize the name from property
>> name = (String) getConfig().getProperties().get(NAME_PROPERTY);
>> Is this code a deserialization from Config to SharedObject? Why name do
>> not replicate with SharedObject automaticaly?
> This code is only executed on the non-primary copy of the shared
> object (i.e. the replicas).  This code (run only on the primary copy),
> is responsible for serializing the state of the shared object (in this
> case, it's name):
>    protected ReplicaSharedObjectDescription getReplicaDescription(ID
> receiver) {
>        // Put primary state into properties and include in replica
> description
>        final Map properties = new HashMap();
>        properties.put(NAME_PROPERTY, name);
>        return new ReplicaSharedObjectDescription(this.getClass(),
> getConfig().getSharedObjectID(), getConfig().getHomeContainerID(),
> properties);
>    }
> And then the code you quote above sets the name (for the replicas) to
> the value specified by the properties included in the
> ReplicaSharedObjectDescription.  The serialization/deserialization of
> shared object state is done explicitly rather than as
> to give the shared object programmer some control over the
> serialization.  I was/have been thinking of adding some implicit
> serialization of shared object fields (perhaps through annotations
> processing or some such), but for the moment everything is explicitly
> done (via properties).
>> And another question: Does SharedObject API have any listeners that
>> calls when shared object has been added?
> Yes, indeed.  An IContainerEvent of sub-type
> ISharedObjectActivatedEvent is sent to any/all IContainerListeners
> before the shared object is activated, and similarly
> ISharedObjectDeactivatedEvent is sent before the shared object is
> deactivated.  The shared object itself is also asynchronously notified
> as well (the shared object has a message queue and a thread created
> for it to process it's messages...and that's how the initialize method
> gets called on the replicas).
> Scott

Pavel Samolisov

Meet me at:
XMPP/Jabber: samolisov@xxxxxxxxx

Attachment: signature.asc
Description: OpenPGP digital signature

Back to the top