UP Development - 1.Inception

Most Project require a short initial step in which the following kinds of questions are explored

  1. What is the vision and business case for this project?
  2. Feasible?
  3. Buy and/or Build?
  4. Rough estimate of cost
  5. Should we proceed or stop?

- Artifacts in Inception Phase

Use-Case Model : Describe functional requirements, and related non-functional requirements

- Useful Classification

  • Functional requirements vs Non-functional requirements
  • Most of the non-functional requirements are collectively called as Quality Attributes or Quality Requirements
  • Functional requirements are explored and recorded in the Use-Case Model.
  • Other requirements can be recorded in the use cases they relate to, or in the Supplementary Specifications artifacts.
  • The Vision artifact summarizes high-level requirements.
  • The Glossary encompasses the concept of Data dictionary which records requirements related to data, such as validation rules, acceptable values, and so forth.

- Motivation for Use Cases

  • We need a tool to analyze, record, and improve functional requirements
  • Developers must know exactly what they are going to implement
  • A Client must understand what will be implemented

==> Solution : Use Case

- Goals and Stories

  • Clients and End users have Goals (Needs) and want the system to help meet them.
  • Informally, Use Cases are Stories of using a system to meet goals
  • The most effective way to capture the Goals and system’s Functional requirements is writing Use Cases

- Actors

  • Basic Definition
    An Actor is anything outside SuD that interacts with SuD.
  • Extended Definition
    An Actor is anything with behavior, including the SuD itself when it calls on the services of other actors
  • In case of a person acotr, it represents a role that the person plays when interaction with these use cases.

- Types of Actors

  • Primary Actors
    Goals 을 달성 하기 위해 System 을 이용함.
  • Supporting Acotrs
    Primary Actor 를 도와주기 위해 System 을 이용함.
  • Offstage Actors
    It has an interest in the behavior of the use case, but is not primary or supporting actors

- Scenarios ( 하나의 특정 사례 )

  • A Scenario ( use case instance ) is a specific sequence of actions and interactions between actors and the SuD to meet a common goal
  • It is one particular story of using a system, or one path through the use case.

- Use Cases

  • Informally, Use Case is a collection of related success and failure scenarios that describes actors using a system to support a goal
  • UP Definition : Use Case is a set of use-case instances, where each instance is a sequence of actions that yields an Observable Result of Value (Benefits) to a particular actor
  • Use Cases document the behavior ( Functional Requirements ) of the system From the User’s Point of View
  • A software product implements a set of use cases