- Let's Review that Process...
- Meet Neil & Gordon...
- Task List
- The Development Process
- ...One More Time
- System Design
- Agile Waterfalls
- Use Cases
- What If...?
- UML State Diagrams
- An Example
- Specification Components
- User Requirements
- ...One More Time
- Creating executables
- Compiled or Interpreted?
- Just-in-Time...
This chapter is from the book
This chapter is from the book
This chapter is from the book
An Example
The abstract diagram on the previous page probably doesn’t look all that helpful, but let’s look at a real example. Here’s the supplier use case in both formats...
Ideal Case
- System displays list of products, alphabetically by type (vegetable, meat, herb, etc.).
- User selects item from list; system displays top three suppliers, ordered by preference. For each supplier, display name, phone number, and delivery days.
Ingredient Not Found
System transfers user to ingredient maintenance screen.
System Error
System displays descriptive message.
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What do you think? Is the diagram clearer? Which would you use for a simple case like this? Either, both?
Put on Your Thinking Hat
The use cases we’ve been working with were very simple. Here’s one that looks a bit more complicated. Prepare a use case and a state diagram based on Gordon’s description.
“Our desserts use basic components—cake layers, fillings like chocolate ganache and pastry cream, and sometimes frostings—that are made in advance and then combined on the day they’re served in the cafe. At the end of each day I prepare the dessert menu for the next day, and to do that I need to know what components and raw ingredients are in the cooler. Because some things may be needed for a catering job, the system needs to show me how many are available in total and how many are already allocated. Then, if we’re getting low on something, I need to add it to the schedule to be prepared sometime in the next few days.”
How’d You Do?
It’s fine if your answers don’t match mine exactly, as long as you thought through the issues.
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