文件名称：CORBA NotificationService
文件大小：1.71MB
文件格式：PDF
更新时间：2011-01-02 17:08:19
CORBA NotificationService of
This specification describes a CORBA-based Notification Service, a service which
extends the existing OMG Event Service, adding to it the following new capabilities:
• The ability to transmit events in the form of a well-defined data structure, in
addition to Anys and Typed-events as supported by the existing Event Service.
• The ability for clients to specify exactly which events they are interested in
receiving, by attaching filters to each proxy in a channel.
• The ability for the event types required by all consumers of a channel to be
discovered by suppliers of that channel, so that suppliers can produce events on
demand, or avoid transmitting events in which no consumers have interest.
• The ability for the event types offered by suppliers to an event channel to be
discovered by consumers of that channel so that consumers may subscribe to new
event types as they become available.
• The ability to configure various quality of service properties on a per-channel, perproxy,
or per-event basis.
• An optional event type repository which, if present, facilitates the formation of filter
constraints by end-users, by making information about the structure of events which
will flow through the channel readily available.
The Notification Service defined here attempts to preserve all of the semantics
specified for the OMG Event Service, allowing for interoperability between basic
Event Service clients and Notification Service clients. To recap, the OMG Event
Service supports asynchronous exchange of event messages between clients. The Event
Service introduces event channels which broker event messages, event suppliers which
supply event messages, and event consumers which consume event messages.