Mr Southerby as CEO needs access to management information. Fred Smith as Order Entry Clerk needs to enter orders. Sometimes Mr Southerby may need to enter an order when Fred isn't there. That doesn't mean that we draw an arrow between Mr Southerby and the Enter Order use case. Entering orders is not the role of the CEO. This is Mr Southerby taking on the role of Order Entry Clerk, a mapping which occurs when Mr Southerby logs on and is granted access to the Enter Order use case by security settings defined by the system administrator.
|Ultimately an actor has no properties other than its links to use cases. It is a logical set and nothing more. When naming actors we need to think of the role that a person takes on rather than their title. Most job titles involve the putting on of a number of different hats in different situations. So name the actor with the role rather than the job title if there is any confusion. Think hats!|
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