advanced use case diagram and model
TRANSCRIPT
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• Are UML behavior diagrams, a business analyst can start the project by preparing Use Case Diagrams
• Use case diagrams were originally proposed by Dr. Iver Jacobson when he was working at Ericsson
• Use cases represent the functionality of system and they capture interaction of human and non human entities called actors with the system.
• System or Subsystem for which Use Case Diagram is prepared is called Subject
• Use case notations include : System Boundary, Actor, Use Case and Relationships
• Use case scenarios : Same use case in its different instance can take up a different scenario. For example for Use case Withdraw cash for different instances scenarios can be : 1) Inadequate Cash Available hence do not dispense 2) Adequate Cash hence dispense 3) Adequate cash but currency denomination as asked for not available hence do not dispense 4) Adequate Cash but customer account is not having adequate balance
Notation for Use case is ellipse. Use case name can be written inside or below the ellipse. The name can contain text, numerals. Strings etc except colon (:) For a multiple worded Use case first word is upper case and subsequent words are lower case with space
Actors are people or systems which interact with Use cases. Actor role name is written below the notation of actor which is a Stick man.
Relationship between actor and an use case is shown by a solid line
System boundary is shown by a rectangle. Use cases which lie inside are the functionality of the system
Arrow initiates from the specialized actor and points towards the towards the more general actor . For the sake of understanding an MD Doctor who can perform complex surgeries and also routine surgical procedures is specialized. An MBBS who is trained in routine surgical procedures is generalized actor.
Arrow initiates from specialized use case name and towards generalized use case. E.g. Bill payment is Generalized use case and Bill payment through cheque, DD or cash are specialized use cases
Arrow initiates from including use case and points towards included use case. For example if after a particular transaction SMS is invariably send then Transaction (including use case) includes Send sms which is (included use case)
Some times one use case may optionally extend its functionality to another use case. Arrow initiates from extending use case to extended use case
A Flipped rectangle is notation for condition. It is used in extend relationship between use cases. Any condition is written within curly brackets
A Flipped rectangle is notation for comment. It is used for any comment or explanation
Primary Actors Initiate the Use Case. Secondary actors do not initiate the Use Case. For example if we have a banking system in which whenever the account holder withdraws cash an information SMS is sent to the a/c holder through SMS Software here the Account holder is Primary actor and SMS software is Secondary Actor
Method 1: Write in a paragraph sequence of activities happening in a use case Method 2: For ever actor prepare a table which will have two columns, column on the left will have actor stimuli and column on the right will mention system response Method 3: Any other procedure or Standard document template used in your organization
This is electricity bill payment process of PVVNL Ltd Electricity subscribers or their representatives collectively called Bill payees can make the bill payment by going to the local electricity office and handing over cheque or demand draft or cash to the Bill receiver. Bill receiver updates the payment in the electricity bill payment system. Alternatively the bill payees can make the payment online through credit card, debit card, net banking or cash. The online payment is received by DPS Transact system which is the payment gateway service of DPS bank. Under both the payment methods after the payment is received an SMS is sent to the subscriber by SMS software system which is invoked through Electricity Bill Payment System
• Any one (Electricity Subscriber or his representative)can make the bill payment if they have District Name, Book Number, Connection Number and Division Name of the Subscriber)
• Electricity bill payment software allows its subscribers to view their bill and payment details online. For the same every electricity subscriber is provided with a subscriber id and password . Through this subscriber id and password a subscriber can view his bills and corresponding payments. To make the online bill payment a bill payee does not need the subscriber id and password.
• Electricity bill payment software is managed by an administrator who can view master reports (total amount outstanding etc.), disallow payments by cheque for individual subscribers if their cheque have bounced earlier and also receive bill payments if any particular bill receiver is absent
Identify Actors Bill Receiver Administrator SMS Software Bill Payee Subscriber
Receive bill payment Payment by cheque Payment by cash Payment by dd Send sms View master reports Disallow cheque payment View payment reports