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11.7. Externalization Service

This service defines the means for converting objects into a form suitable for export over general media, such as network streams or disk storage, and then re-constituting this data back into object references, potentially in a different ORB and/or process. The service allows for pluggable data formats for externalized objects, but a standard serialized format for objects is provided, to ensure that a baseline protocol can be shared among users of the service.

The Externalization Service uses a Stream object for externalizing and internalizing objects. A StreamFactory creates Stream objects. Specific sources or destinations for streams can be supported by subclasses of the StreamFactory (e.g., FileStreamFactory). Objects that are to be externalized must extend the Streamable interface.

This service uses the Life Cycle Service to create and destroy Stream and StreamFactory objects. The Relationship Service manages the externalization of graphs of related objects.

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