Actors
Actors are the entities that interact with your system or are interacted upon by your system. They do not have to be real people only. They can be other systems, subsystems, external databases, etc. Basically, anything that your system does not have full control over and is acted on or upon by your system, is an actor.
The actor notation is a stick figure.
Do not use cutesy pictures, clipart or pictures of actual people. Stick figures, and only stick figures. Genderless, raceless, non-judgemental stick figures.
Within your system, actors will represent the different roles within the company and what they can do in your system. You will obviously have many different actors ranging from Chief Technical Officer to Secretary; Lecturers to Students. If an entity has different things it can do in your system (use cases), it should be represented as a separate actor.
Actors are only entities and components that you do not have control over. For example, your own database is not an actor, however an external database (e.g. FBI Criminal database) is.
For the sake of general consistency, keep your actors on the left side of your use cases, and external actors on the right.
Within SPAMS, there will be four distinct roles:
- Administrators,
- Lecturers,
- Assistants, and
- Students.
SPAMS will also interact with the University’s Biographic Database to draw the student’s biographical data.
The diagram above shows how each of these four roles, and one external system, are translated into actors. Even though the Biographic Database is not a person, it is still indicated by a stick figure.