A set of Instances for a Domain Model. Remember that names are not objects.
Types
Agent
Active, autonomous object
- Instances have individual behaviour and a sequence of state transitions for their state variables
Entity
Autonomous, passive object
- Instances can exist in the system independently of instances of other objects
- Cannot control behaviour of other objects
- Usually has persistent state
- Things that do not initiate action
Event
Instantaneous object
- Exist in a single system state
- Represents occurrences and actions in a point of time
Associations Object to object links
- Objects that depend on other objects that they link
- Represents conceptual relationships