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Describe the use case for the log-in process of the on-line Bookstore system.
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ONLINE USE CASE DIAGRAM FREE SOFTWARE
Use Case Diagrams Obviously, actor and use case names must be unique within a given diagram Consider use cases to be similar to classes: A use case describes an activity that is possible A given system may have several instances of that activity throughout its lifetime A use case is a (coarse-grained/large) unit of behaviour, and a class is a unit of software Ī simple example Example: In an on-line Bookstore system, user needs to log-in first before he/she could order and purchase any desired books. Use Cases For the auction website example, a system administrator can act in two roles: Administrator Customer Īuction Website Use Cases Auction Website Search for item Place bid Put item up for auction Register account Customer eBay) The actor customer might: Register for an account Search for items by keyword Place a bid on an item Put an item up for auction Check the status of this item Īctors An actor represents a role that a user might play For example, a network administrator at a company might play the following roles: NetAdmin Employee Each role must be represented separately Use Cases For an example, consider an auction website (e.g. Use Case Diagrams Use case diagrams consist of at least two components: An actor Actors are represented as stick people, with a label below, naming the actor's role There may be multiple actors in a diagram A use case Use cases are represented as ellipses, with a label inside, naming the use case There may be multiple use cases in a diagram Use Case Diagrams Use case diagrams describe relationships between users and use cases A use case is a (usually high-level) user activity in the system A use case is a collection of related success and failure scenarios that describe actors using a system to support a goal A use case name should generally begin with a verb