An event is something that happens, to which an element may choose to respond. Events can be responded to by any element. Similarly, events may be generated (emitted) by any element. Knowing the events generated or responded to by an element makes it easier and more transparent to interact with that element. Note that some events may occur whether generated or responded to by an element or not. The concept of event is captured by the Event OWL class:
Figure 1. SOA-O Event Class.
Event as a concept is generic and has relevance to the domain of SOA as well as many other domains. For the purposes of this ontology, event is used in its generic sense.
From a design perspective events may have more granular parts or may be expressed and made operational through specific syntax or semantics. We have chosen to stay at the concept level and not include such design aspects in the ontology.
generates and generatedBy Properties
Events can, but need not necessarily, be generated by elements. The generates property, and its inverse generatedBy, capture the abstract notion that an element generates an event.
Note that the same event may be generated by many different elements. Similarly, the same element may generate many different events.
respondsTo and respondedToBy Properties
Events can, but need not necessarily, be responded to by elements. The respondsTo property, and its inverse respondedToBy, capture the abstract notion that an element responds to an event.
Note that the same event may be responded to by many different elements. Similarly, the same element may respond to many different events.