UML Exercise: Automated Teller Machine (ATM)
Brief Statement of Purpose:
An ATM is an electronic device designed for automated dispensing of money. A user can withdraw money quickly and easily after authorization. The user interacts with the system through a card reader and a numerical keypad. A small display screen allows messages and information to be displayed to the user. Bank members can access special functions such as ordering a statement
Brief Summary of Requirements:
The ATM is required:
1. To allow authorized card holders to make transactions
1. Card holders shall view and/or print account balances
2. Card holder shall make cash withdrawals
3. Card holder shall make cash or check deposits
4. Card holder shall quit session
2. To allow bank members to access additional, special services
1. A bank member shall be able to order a statement
2. A bank member shall be able to change security details (e.g. PIN number)
3. To allow access to authorized bank staff
1. Authorized staff can gain access to re-stock the machine
2. Authorized staff are able to carry out routine servicing and maintenance
4. To keep track of how much money it contains and alert bank staff when stocks are getting low.
Additional Notes:
Users shall be able to access the ATM by punching in their account number and PIN. Once the system has verified that the account is active and the PIN matches with the account number, the system offers the users four choices. Users can withdraw money, deposit money, check balance or quit the session.
The user must have a minimum of $100 in his / her account. At the end of any transaction a printed copy of the transaction is provided to the user. A transaction could be - withdraw money, deposit money or check balance. Once the user has completed a transaction, the system offers the user the same four choices, until the user decides to quit.
The system shall interface with the device to dispense cash, the device to accept cash or check and the printer. Since we have not studied databases in this course, the system will keep all the information in two RandomAccess files. One file will hold the passwords and the other account balances.
- Identify and list the actors
- Identify and list the uses cases
- Draw the top level Use-Case diagram
- Give a detailed Use-Case analysis for one use case. Your analysis should contain a brief description of the use case, the basic and alternative flows, pre and post conditions.
- Identify and list nouns of the system to assist in developing initial Class diagram
- Draw initial Class diagram
- Draw Sequence diagram