Defines the contract for implementations which know how to scope the notion
of a
current session.
Implementations should adhere to the following:
- contain a constructor accepting a single argument of type
SessionFactoryImplementor
- should be thread safe
- should be fully serializable
Implementors should be aware that they are also fully responsible for
cleanup of any generated current-sessions.
Note that there will be exactly one instance of the configured
CurrentSessionContext implementation per
SessionFactory.