chap7 需求分析-用例图教学讲义.ppt

Conversion Notes The material in this chapter is an expansion of material previously found in Chapter 6 and Module A. This slide explains the industry problem that this material addresses. Teaching Notes If possible, the instructor should share real-life experiences in misunderstood or mis-specified system requirements. To illustrate the inadequacy of data and process models, show the students some of the models from chapters 8 and 9. As them as novices if they can understand them. No additional notes No additional notes No additional notes Teaching Notes Definitions for these symbols are on the next slide. Teaching Notes Using use-case modeling encourages user involvement. By the same token, for use cases to be successful participation by the user is imperative. Teaching Notes use-case diagrams and use-case narratives are two views of the same sequence of steps that make up a conceptual use-case. The use-case diagram communicates at a high level the scope of the business events that make up the Use-case. The use-case narrative communicates at a more detailed level exactly how the user interacts with the system. A use-case itself is not considered a functional requirement, but the use-case’s story, or scenario, consists of one or more requirements. Teaching Notes Definitions for these symbols are on the next slide. Teaching Notes Use cases are the results of deconstructing the scope of system functionality into many smaller statements of system functionality. Use cases describe the system functions from the perspective of external users and in the manner and terminology in which they understand. An actor initiates system activity, a use case, for the purpose of completing some business task. An actor represents a role fulfilled by a user interacting with the system and is not meant to portray a single individual or job title. Have students provide examples of temporal events (nightly download, monthly billing, etc.). No additional notes. No additional notes. No