event
Events are relevant state transition classes, i.e. an event is defined as a set of relevant state transitions for a structure or property. In contrast to other theories, events are not considered as functions or methods, but as state transitions of instances stored in the database.
Events are divided in user-defined events, system events and time events.
Events can be handled by appropriate event handlers, which can be implemented in context classes linked to properties or object types.
Generalisations: feature