Object connectivity through loosely coupled publish and subscribe events

A computer-readable storage medium having computer-executable program code stored thereon to implement an object-oriented event communications model for distributing events from a publisher to any subscribers of the events, the publisher being programmed to issue an event as a call to a method on an outgoing event interface exposed by an object which outgoing event interface and object are identified by unique identifiers defined for the publisher, the program code comprising:

• code associating the unique identifiers to an event distribution object class having the outgoing event interface;
• and
• object server code for supplying an event distribution object of the event distribution object class, the event distribution object having distribution code operative in response to the publisher's call that issues the event so as to distribute the event to the event's respective subscribers;
• wherein the event's subscribers expose counterpart outgoing event interfaces, and the distribution code multi-casts calls to methods on the counterpart outgoing event interfaces matching the publisher's call.

In a computer system, an event distribution object associated with a outgoing event interface definition, an identifier of the event distribution object's class, and an identifier of an outgoing event interface, all defined for a publisher programmed to call methods of the outgoing event interface to cause the event distribution object to distribute events, the event distribution object comprising:

• an outgoing event interface supported by the event distribution object and defined per the outgoing event interface definition of the publisher,
• a plurality of subscribeable methods exposed through the outgoing event interface;
• a multicasting distribution program loop operative in response to a publisher's call to a subscribeable method of the outgoing event interface to determine any subscribers to the subscribeable method and issue calls to counterpart methods of said any subscribers;
• and
• plural subscriptions comprising at least one transient subscription indicating a relationship of a subscriber to an event as indicated by an interface identifier of an instance of a subscriber as a subscriber reference and at least one persistent subscription indicating a relationship of a subscriber to an event as indicated by a class identifier as a subscriber reference;
• wherein the outgoing event interface supported by the event distribution object matches an interface to counterpart methods of said any subscribers.