4. Sequence Diagrams

Try these first

1. 1.

   What is a sequence diagram used for?

   Hint

   Think about message exchange in systems.

2. 2.

   What does a lifeline represent?

   Hint

   Consider who is involved in the interaction.

3. 3.

   What is the primary purpose of a sequence diagram?

   • To show graphics
   • To illustrate system interactions over time
   • To create use case scenarios

   Hint

   Consider what you learned about system interactions.

4. 4.

   True or False: Activation bars show when an object is inactive.

   • True
   • False

   Hint

   Think about the definition of activation bars.

5. 5.

   Construct a sequence diagram for an online food delivery process, detailing user actions, backend interactions, and delivery completion.

   Hint

   Break down each step carefully.

6. 6.

   Evaluate a sequence diagram for a failed login attempt. Discuss the potential failures in interaction.

   Hint

   Think about what could disrupt the normal flow.