18-649 Scenarios and Sequence Diagrams

18649 Spring 2010
Group 7 - Justin Ray / justinr2

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Scenarios:

• Use Case 1
• Scenario 1A
• Scenario 1B
  
• Scenario 1C
• Use Case 2
• Scenario 2A
• Use Case 3
  
• Scenario 3A
  
• Use Case 4
  
• Scenario 4A
• Scenario 4B

Use Case 1: Customer inserts a quarter

Scenario 1A: Customer inserts a coin when the cost of a soda has not been reached

Author:  Justin Ray/justinr2

Pre-Conditions:

• The soda machine is not vending.
• No button is pressed.
• The system has received fewer coins than the cost of a soda since the last vend cycle.
  

Scenario:

1. The customer inserts a coin.

Post-Conditions:

• The soda machine has one additional coin for this vend cycle.
  

Sequence Diagram:

SD Audit

1. Name of the person conducting the audit? Justin Ray/justinr2
   
2. Are the events in the sequence diagram consistent with the steps in the scenario?  yes
   
3. Are all arcs labeled with a valid command in the sequence diagram? yes
   
4. Are all arcs correctly colored (blue for physical message, black for network messages)? yes
   
5. Are all boxed items correct parts of the elevator architecture? yes
   
6. Does each message arc in the sequence diagram originate from the correct object (according to the interfaces defined in the Requirements I and II documents)? yes
   

Scenario 1B: Customer inserts a coin when the cost of a soda has been reached but no button pressed

Author:  Justin Ray/justinr2

Pre-Conditions:

• The soda machine is not vending.
• No button is pressed.
• The system has received the correct number of coins for the cost of a soda since the last vend cycle.
  

Scenario:

1. The customer inserts a coin.
2. The coin is returned.
   

Post-Conditions:

• The soda machine has the same number of coins.
  

Sequence Diagram:

SD Audit

1. Name of the person conducting the audit?  Justin Ray/justinr2
2. Are the events in the sequence diagram consistent with the steps in the scenario? yes
   
3. Are all arcs labeled with a valid command in the sequence diagram? yes
   
4. Are all arcs correctly colored (blue for physical message, black for network messages)? yes
   
5. Are all boxed items correct parts of the elevator architecture? yes
   
6. Does each message arc in the sequence diagram originate from the correct object (according to the interfaces defined in the Requirements I and II documents)? yes
   

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Scenario 1C: Customer inserts a coin while holding down a soda button

Author:  Justin Ray/justinr2

Pre-Conditions:

• The soda machine is not vending.
• Soda button s is pressed.
• The system has received the one less than the correct number of coins for the cost of a soda since the last vend cycle.
• The VendCarriage is parked in front of chute r, r > s.

Scenario:

1. The customer inserts a coin.
2. The light on the soda button s begins flashing.
3. The VendPositionControl aligns with soda chute s.
4. The soda is vended.
5. The light on the soda button s stops flashing.
   

Post-Conditions:

• The system retains the cost of the soda and has one less soda of type s.

Sequence Diagram:

SD Audit

1. Name of the person conducting the audit?  Justin Ray/justinr2
2. Are the events in the sequence diagram consistent with the steps in the scenario? yes
   
3. Are all arcs labeled with a valid command in the sequence diagram? yes
   
4. Are all arcs correctly colored (blue for physical message, black for network messages)? yes
   
5. Are all boxed items correct parts of the elevator architecture? yes
   
6. Does each message arc in the sequence diagram originate from the correct object (according to the interfaces defined in the Requirements I and II documents)? yes
   

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Use Case 2: Customer pushes a soda button

Scenario 2A: Customer pushes a soda button when the correct amount has been paid

Author:  Justin Ray/justinr2

Pre-Conditions:

• The soda machine is not vending.
• No button is pressed.
• The system has received the correct number of coins for the cost of a soda since the last vend cycle.
• The VendCarriage is parked in front of chute r, r < s.
  

Scenario:

1. The Customer pushes soda button s.
2. The light on the soda button s begins flashing.
3. The VendPositionControl aligns with soda chute s.
4. The soda is vended.
5. The light on the soda button s stops flashing.
   

Post-Conditions:

• The system retains the cost of the soda and has one less soda of type s.
  

Sequence Diagram:

SD Audit

1. Name of the person conducting the audit?  Justin Ray/justinr2
2. Are the events in the sequence diagram consistent with the steps in the scenario? yes
   
3. Are all arcs labeled with a valid command in the sequence diagram? yes
4. Are all arcs correctly colored (blue for physical message, black for network messages)? yes
5. Are all boxed items correct parts of the elevator architecture? yes
6. Does each message arc in the sequence diagram originate from the correct object (according to the interfaces defined in the Requirements I and II documents)? yes

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