How to obtain the information needed for the development of the use case model in the real world?

Question

How one could obtain relevant information for the development of the case model. What is the correct approach?

Answer 1

@Ister is right : capture customer's needs correctly is a whole topic and a complex one.

There are some hints which can be provided:

• If you get a state of work, this is the first source

• If you get a real customer, after the state of work, workshops about his business and his business processes is the a source

• If you want to realize a software with competitors, looking to competitors products is a way to find use cases

• State of the art of the domain is also a source

• Interview with actors of the domain may be a source

• If you work in a domain such as transport, army, medical; there are some norms which can be used to define use cases

• Doing UI mock up could be a way to define use cases and business processes. Espacially with non "it aware" guys. The UI is done to realize the business processes, so to show ui mock up may help some customers to define their needs.

• your own experience

Answer 2

It is related what Methodology you are using. The steps of your methodology prepare your input about Use Case Modeling.

For example in RUP based methodologies, the inputs of Use Case Modeling are:

• Capture a Common Vocabulary
• Manage Dependencies
• Review Requirements
• Detail a Use Case
• Detail the Software Requirements
• Identify Targets of Test
• Identify Test Ideas
• Identify Test Motivators
• Prioritize Use Cases
• Architectural Analysis
• Assess Viability of Architectural Proof-of-Concept
• Use-Case Analysis
• Define Test Approach
• Structure the Use-Case Model

You can find:

• complete guides of Use Case Modeling
• inputs of Use Case Modeling
• outputs of Use Case Modeling
• Examples
• and etc.

in this site.

However, it can be different in other Methodologies.