Vending Machine Use Case Diagram

The assignment content describes a vending machine system with various use cases, including user authentication, drink preparation, stock level management, cash level management, accounting information, and maintenance services. The functional requirements include checking stock levels, checking cash levels, logging in, checking accounting information, handling drinks, and servicing the machine. The non-functional requirements include validity, consistency, completeness, verifiability, and security.

vending machine assignment
Student name:
05 November, 2016

Contents
USECASE DIAGRAM...............................................................................................................................2
USECASE DESCRIPTION..........................................................................................................................3
FUNCTIONAL REQUIREMENTS, NON FUNCTIONAL REQUIREMENTS AND THEIR VERIFICATION...........8
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USECASE DIAGRAM
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USECASE DESCRIPTION
ID: U1
Name: Coins insert
Description: process includes insertion of coins into the machine
Pre-condition: select coin value to be inserted
Event flow:
1. User selects the coin value
2. Inserts the coins
Post-condition: coins are sent for value validation
Includes: none
Exception: none
Triggers: selection of coin value
ID: U2
Name: validation
PRE-CONDIITON: coins are inserted into the system and value is also selected
DESCRIPTION: this process validates the coins inserted against the value selected
POST CONDITION: coins are successfully validated and accepted.
EVENT FLOW:
1. Coins are inserted into the machine
2. Value is compared with the selected value.
3. If coin value > or = selected value, coins are accepted.
EXCEPTION: if coins inserted value is less than the selected value, coins are ejected back for the
customer
INCLUDES: coins_insert
TRIGGERS: insertion of coins
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ID: U3
NAME: drinks
PRE-CONDIITON: drink is selected from the menu
DESCRIPTION: this process prepares the drink, dispense it and then clean the vessel.
EVENT FLOW:
1. Drink is selected from the menu
2. Drink is prepared and dispensed to customer gateway.
3. Vessel is cleaned for next drink.
POST CONDITION: drink is provided to the customer
EXCEPTION: none
INCLUDES: coins insert, validate
TRIGGERS: selection of drink
ID: U4
Name: add recipe
PRE-CONDIITON: service operator is logged in
DESCRIPTION: the recipe of the drinks can be altered or added.
POST CONDITION: the recipe data is updated
EVENT FLOW:
1. The user logs in to the system
2. Alter the recipe or adds it.
EXCEPTION: none
INCLUDES: login
TRIGGERS: none
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ID: U5
Name: stock level
PRE-CONDIITON: user is logged in into the system
DESCRIPTION: the user can check stock level or update them
POST CONDITION: the stock levels are updated.
EVENT FLOW:
1. User logins into the system
2. Check or updates the stock levels
3. File updated
EXCEPTION: none
INCLUDES: login
TRIGGERS: none
ID: U6
Name: cash level
PRE-CONDIITON: user is logged in into the system
DESCRIPTION: the user can check cash level.
POST CONDITION: none
EVENT FLOW:
1. User logins into the system
2. Check the cash levels
EXCEPTION: none
INCLUDES: login
TRIGGERS: none
ID: U7
Name: login
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PRE-CONDIITON: the user has valid id and password
DESCRIPTION: the service operator uses this function to login into the system.
POST CONDITION: user is logged in
EVENT FLOW:
1. User enters id and password.
2. Upon validation from database, user is logged in.
EXCEPTION: if id or password is incorrect, user is asked to enter the correct details again
INCLUDES: none
TRIGGERS: none
ID: U8
Name: CREATE NEW ACCOUNT
PRE-CONDIITON: NONE
DESCRIPTION: new account for service operator is created
POST CONDITION: account is created
EVENT FLOW:
1. User details are entered.
2. Id and password is created and provided to user.
3. Account is created.
EXCEPTION: none
INCLUDES: none
TRIGGERS: none
ID: U9
Name: accounting info
PRE-CONDIITON: user is logged in
DESCRIPTION: user can check accounting info or get reports.
POST CONDITION: file updated on updates done
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EVENT FLOW:
1. User logs in into the system
2. Checks the accounting info
3. Updated the info if required.
4. Database file is updated.
EXCEPTION: none
INCLUDES: login
TRIGGERS: none.
ID: U10
Name: service login
PRE-CONDIITON: service engineer has passcode
DESCRIPTION: service engineer logins into the system for servicing or maintenance purpose.
POST CONDITION: user is logged in
EVENT FLOW:
1. User enters passcode
2. Upon validation from database, user can now perform service
EXCEPTION: if passcode is incorrect, user is asked to enter the correct details again. If the passcode is
not entered in given time, alert process activated.
INCLUDES: alert
TRIGGERS: none
ID: U11
Name: alert
PRE-CONDIITON: service engineer has passcode
DESCRIPTION: alert is sent to service operator if engineer doesn’t enter passcode in the given time
POST CONDITION: service operator is alerted.
EVENT FLOW:
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1. User does not enters passcode in given time
2. Upon time lapse, alert sent to service operator.
EXCEPTION: none.
INCLUDES: service login
TRIGGERS: entering or not entering the passcode.
ID: U12
Name: machine service
PRE-CONDIITON: service engineer entered the correct passcode to put machine in service mode.
DESCRIPTION: the engineer performs service on the machine
POST CONDITION: machine is serviced and closed.
EVENT FLOW:
1. Service engineer logs in
2. Puts machine on service mode.
3. Collects cash
4. Repairs or perform service
5. Close machine
EXCEPTION: none
INCLUDES: service login
TRIGGERS: successful service login into the system.
FUNCTIONAL REQUIREMENTS, NON FUNCTIONAL
REQUIREMENTS AND THEIR VERIFICATION
The functional requirements are:
1. Service operator must be able to check stock level.
Verification: stock level use case
2. Service operator must be able to check cash levels
Verification: cash levels use case
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3. Service operator must be able to login into the system
Verification: login use case
4. Service operator must be able to check accounting info
Verification: accounting info use case
5. Service operator must be able to handle the drinks the system prepares
Verification: drinks use case
6. Customer must be able to insert coins and get the drinks
Verification: coins insert, validation, drinks use cases
7. Service engineer must be able to repair or service the machine
Verification: service login, machine service use cases
The non-functional requirements are:
1. Validity: the system has all the requirements covered in the Usecase for example drinks,
cash, stock, login etc.
2. Consistency: There are no requirement conflicts. All the user requirements have been
designed into the use case without any inconsistent elements.
3. Completeness: the system design is a complete picture as per the scenario, that is, all the
requirements have been added into the system.
4. Verifiability. The design is verifiable and can be cross checked with scenario.
5. Security: features of alert, service login and login have been added into the system. Only
correct user id and password will be accepted from the user in order to login. Next only
correct passcode from service engineer will be accepted else alert will be generated and
sent to service operator.
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