Small Test: Bank account manager

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Small TestBank account manager

• System has to run on an automated teller machine.
• User must be able to deposit checks into the
  account.
• User must be able to draw money from the account.
• User should be able to query the balance of
  his/her account.
• The user should get a receipt for a transaction
  on request. The transaction type (withdrawal or
  deposit), the transaction date, the account
  number, the amount, and the new balance should be
  visible on the receipt.
• After each transaction the new balance should be
  displayed to the user.

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Perfect solution (1)
3
Perfect solution (2)
Not enough money???
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Near miss (1)

• ltltincludegtgt in wrong direction
• includes and extends not dashed

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Near miss (2)
ltltextendgtgt in wrong direction
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Near miss (3)

• Undirected associations
• includes and extends not dashed

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Near miss (4)

• Receipt not optional
• includes not dashed

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Near miss (5)

• ltltusesgtgt association between actor and UC
• extends and includes not dashed

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Errors you should prevent (1)!
Undefined relationships
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Errors you should prevent (2)!

• System not a UC
• Sequence descriptions instead of Ucs

11
Errors you should prevent (3)!

• get users pwd not a UC
• Sequence description
• unnamed relationships

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Errors you should prevent (4)!

• Rectangles?
• unnamed relationships
• Sequence descriptions
• Menu not a UC

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Errors you should prevent (5)!

• Rectangles?
• Unnamed relationships
• Sequence/control flow descriptions

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Errors you should prevent (6)!

• Rectangles?
• ltltextendgtgt in wrong direction
• ltltextendgtgt instead of ltltincludegtgt
• Data structure description
• Incorrect use of ltltincludegtgt

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Errors you should prevent (7)!

• Multi-referenced extension UC
• Undirected, undashed includes and extends

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Errors you should prevent (8)!

• Level of granularity too low
• ltltextendgtgt between actor and UC

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Errors you should prevent (9)!

• Validate user is the only functionality
  provided to user?
• ltltincludegtgt in wrong direction

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Errors you should prevent (10)!

• Description of the user interface elements

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Errors You Should Prevent (11)!

• Teller machine?

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Rules of thumb (1)

• Use the ltltincludegtgt relationship to point to a
  use case describing a (sub-)sequence of action
  that occurs in more than one other use case.

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Rules of thumb (2)

• Use the ltltextendgtgt relationship if a conditional
  expression indicates the presence of alternative
  flows
• Example
• Instead of
• Ask user if she wants a receipt.
• If Yes print receipt on printer
• Use
• (print receipt)

Withdrawmoney
ltltextendgtgt(print receipt)
Withdraw moneywith receipt printing
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Were Available!

• Questions?
• if you have any questions about contents of this
  lecture or other course-related issues, please
  come by during our office hours, or send us email
• Dr. Joshua MTW, 12-1pm, ICT 548
• joshuar_at_cpsc.ucalgary.ca
• Dr. Walker WF, 1-2pm, ICT 546
• rwalker_at_cpsc.ucalgary.ca