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Visual Paradigm for UML Writing Effective Use Case

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Writing Effective Use Case
Written Date : December 08, 2011 Use case analysis is a major technique used to find out the functional requirements of a software system. Use case, an important concept in use case analysis, represents an objective user wants to achieve with a system. It can be in text form, or be visualized in a use case diagram, like this:

The beauty of use case is that it aims at describing a system from external usage viewpoint, rather than from developer's perspective. Therefore, writing use case can be the deciding factor for building a system that meets users' needs. In this tutorial, you will learn how to make use of various functions to write effective use case.

What is a Use Case?

A use case is an objective user(s) wants to achieve with a system. Use cases are named with verb or verb + noun phrase. It is usually short yet descriptive enough to describe a user objective. You are encouraged to use concrete and specific verbs and nouns to avoid ambiguity. Verbs like 'do' and 'perform' and nouns like 'data' and 'information' should be avoided whenever possible. User performs use case to yield observable goal. Take online hotel reservation system as an example. "Make reservation" is undoubtedly a use case as this is what user wants to achieve with the system. The function of looking up a hotel on an online map can also be what a user needs. However, it is not a use case because it is only a part of the reservation process instead of an objective. Some analysts try to make use of use case to describe user interface requirements (e.g. support multiple look & feel), performance requirements (e.g. load in background), deployment arrangement (e.g. ready server) and even implementation level (internal) requirements (e.g. construct database). http://www.visual-paradigm.com/product/vpuml/tutorials/writingeffectiveusecase.jsp Page 1 of 9

Visual Paradigm for UML Writing Effective