Tài liệu Module 5: Analyzing Information: Use Cases and Usage Scenarios doc

Module 1: Course Overview Module 4: Gathering Information Module 5: Analyzing Information: Use Cases and Usage Scenarios Module 3: Characteristics of Information Transitioning to Analysi

Module 5: Analyzing Information: Use Cases and Usage Scenarios

Module 1: Course Overview

Module 4: Gathering Information

Module 5: Analyzing

Information: Use Cases

and Usage Scenarios

Module 3:

Characteristics of Information

Transitioning

to Analysis

Use Cases

Usage Scenarios Review

Module 5: AnalyzingInformation: Use Casesand Usage Scenarios

First, you will look at the relationship between gathering and analyzing business and user requirements Then you will learn how to develop use cases and usage scenarios

After completing this module, you will be able to:

" Describe a process for synthesizing information

" Explain the concepts of use cases and usage scenarios

" Create use cases

" Create usage scenarios

Slide Objective

To provide an overview of

the module topics and

objectives

Information

In this section, you will look at the transition from gathering information about the business challenge to analyzing the information so that you can determine business and user requirements and wants Then you will learn about a general process for synthesizing information

In Activity 5.1, you will participate in a class discussion relating your own experiences to the process of gathering and analyzing requirements and wants

in the Ferguson and Bardell, Inc case study

Slide Objective

To provide an overview of

the topics and activity in this

section

Requirements and Wants

$ What would be nice for the product to do

When you have finished gathering information, you will have a large amount of information that you need to sift through to determine what information is most relevant to the business challenge You need to synthesize the information to create a detailed description of the current state

The information that you gather from different sources will include requirements and wants from the business and user perspectives The requirements indicate what the product or solution needs to do to solve the business challenge as derived from the business and user perspectives The wants indicate what stakeholders and users would like to see in the final product or solution You need to distinguish between requirements and wants when you synthesize the information from both the business and user

perspectives

The requirements and wants will eventually define the features of the final solution At this stage, you will only describe, organize, and prioritize the requirements and wants Later, in the process of developing the product, the development team will determine the features of the product

Some requirements indicate aspects of the business, applications, information,

or technologies that may constrain the final business solution The final business solution must conform to these factors because they are deemed unchangeable For example, a business may have a particular network configuration that cannot be changed in the near future The network may have certain bandwidth limitations that affect how the development team will need to design the final solution As you synthesize the information, you need to document these constraints clearly so that the development team will design a product that conforms to the enterprise architecture of the business

Slide Objective

To summarize the previous

course material and

transition to the next phase

of the course by focusing on

analyzing information for

requirements

Lead-in

As you synthesize

information, you should use

the business and user

Reinforce to students that

requirements and wants are

not necessarily at odds with

each other Users and

stakeholders have a core

understanding of what is

required to improve the

business They also have

desires for features or

capabilities that they know

might not make it into a first

or second release of a

product

As you analyze the information that you have gathered, verify that you have enough information to indicate the current state of the business and product requirements, including:

" The security needs

" The support structures for the solution and their characteristics

" Planned changes in the business that could affect the product design

" The performance that the users expect or that the business needs to remain competitive

" The existing applications, such as legacy systems, that will need to interact with the new product

" How the existing business processes affect the solution

As you synthesize and analyze the information, you can determine any gaps that exist in the information that you collected, and if necessary, gather additional information

When the development team actually develops the final product, it will need to take the product requirements into account The team will also need to

document the effects that the new product may have on the existing environment in terms of new requirements for the business, such as support, maintenance, and extensibility issues The new requirements must also adhere

to the constraints that you documented during analysis

Synthesizing Gathered Information

You should discuss your findings at a debriefing session with other team members At the debriefing session, you will present your findings, diagrams, and notes to each other Comments from members of the project team help to interpret the results, and the session helps the team to better understand the users

Involve as many team members as possible in the debriefing session, especially those from development, testing, user education, and logistics management Team members will contribute different perspectives to the session and walk away from these debriefings with information that is important to them During this session, the different team members should suggest any information that is missing that you need to research

As you analyze the information, you develop information models that describe the current state and provide the following information

Item Description

Context Cultural norms, policies, procedures, rules, regulations, and

standards that constrain and support the business and user

Workflow process

Communication and coordination of many work processes and activities

Process Collection of activities that yield a result, product, or service,

usually a continuous operation

Activity Collection of tasks within a particular process

Task sequence Detailed steps for discrete activities

Task Series of steps associated with a particular role and activity Step Smallest level of action that cannot be decomposed any further Physical

When you synthesize

information, you break it

down into models that

indicate what the final

product must do

Activity 5.1: Transitioning from Gathering to Analyzing Information

In this activity, you will compare your experience in a development project with the process described in this section You will also review the results of your work from the activities in Module 4 in relation to business and user requirements and wants

After completing this activity, you will be able to:

" Describe a process for synthesizing information

" Evaluate the information collected in the Ferguson and Bardell, Inc case study in terms of requirements and wants

Slide Objective

To explain the activity

In this section

After you have synthesized the information, you can develop use cases and usage scenarios to document the business processes and business and user requirements in more detail The use cases and usage scenarios that you develop will provide structure for the development team when they design the solution

In this section, you will focus on use cases You will learn what use cases are and how to create them

In Activity 5.2, you will develop use cases for the Ferguson and Bardell, Inc case study

Slide Objective

To introduce the section and

activity

Use Cases Defined

actor performs in a dialogue with a system to provide measurable value to the actor

" Illustrate:

$ Business context

$ Users and their activities

$ Physical environment

Use cases show the functionality of a system and how an actor interacts with the system to obtain value

The purposes of use cases are to:

" Identify the business process and all activities from start to finish

" Document the context and environmental issues

" Trace a path between business needs and user requirements

" Describe needs and requirements in the context of use

" Focus users and the development team

Use cases provide the following benefits:

" Provide context for requirements

" Facilitate common understanding

" Provide the basis for usage scenarios

" Facilitate objectivity and consistency in evaluating user suggestions

The following list provides examples of use cases for a customer contact database in a training center In the examples, the actor is a sales consultant and the system is contact management software

" Enter customer information

" Print customer mailing label

" Sort customers by courses taken

" Delete inactive customer

Slide Objective

To define use cases and

provide examples

Lead-in

Use cases describe the

interaction between an actor

and a system

The examples use prose to describe the use cases You can also use diagrams to describe use cases Typically, an actor is shown as a stick figure, the use case is shown as an ellipse, and a set of cases can be enclosed in a box representing a system The following diagram shows a simple use case diagram for the training center

Sort customers by classes taken

Enter customer name

Print customer mailing label

Delete inactive customer

Contact management system

SalesRepresentative

In this course, you will use prose descriptions when developing use cases The use cases that you develop will describe a workflow process in more detail A workflow process depicts the flow of products and information within a high-level business process The workflow process indicates the interaction of different systems and actors For example, a workflow process for the training center would depict the interaction between marketing, course registration, and final course delivery to a customer Similar to use cases, you can describe workflow processes by using prose or diagrams

Your focus in this course is on developing current state use cases During the planning process, the development team will create future state use cases that show how the requirements are incorporated into the new system to improve existing processes or create new processes

The current state use cases are essential for the development team to develop a product that addresses the business and user requirements

" List the high-level interactions

$ Describe a single behavior that is important in the process

$ Describe each behavior clearly

A system is a collection of subsystems that have a real-world purpose

For example, in the training center example, a billing system might have a subsystem that determines applicable discounts for a customer invoice Another subsystem might calculate the appropriate tax for an invoice When you develop use cases, identify a single system or subsystem A collection of use cases will indicate the relationships among the subsystems that make up a system, as well as the relationships between systems that interact with each other

The actor is an integral part of the use case The use case is all about interactions between an actor and the system An actor can be a real person or another system

For example, in the training center, customers might be given a discount after taking 10 courses A billing system could query the customer management system to determine the number of courses taken by a customer In this example, the billing system is an actor that interacts with the customer management system to determine whether to provide a discount to a customer After you have identified the system and the actor, describe the interaction between them Describe only a single interaction Create one use case for each interaction Describe only those interactions that are important to the business challenge and the vision statement

Verify that the use cases capture an entire process in detail In the set of use cases, document the process in such a way that anyone can view the use cases and understand the activities within the process

When describing systems as they function in the current state, be sure to capture information about how the system is currently working, and not just focus on the users’ feedback regarding how they want the new system to function

Slide Objective

To explain how to create a

use case

Activity 5.2: Creating Use Cases

To completely describe and understand a process, you can create use cases that describe all of the interactions between the actors and a system

In this activity, you will create use cases for the timesheet process used by the administrative assistants and the consultants You will use the results of this activity in Activity 5.3

After completing this activity, you will be able to:

" Create use cases

Slide Objective

To introduce the activity

In this section

Use cases describe the high-level interactions between an actor and a system Together, the use cases provide a description of a workflow process You develop usage scenarios to provide even greater detail about the process Usage scenarios provide additional information about the activities and task sequences that constitute a process

In this section, you will learn what usage scenarios are and how to create them

In Activity 5.3, you will create usage scenarios for the use cases you developed

in Activity 5.2

Slide Objective

To introduce the section and

activity

Usage Scenarios Defined

" Illustrate a particular instance of a use case

$ Single sequence of object interactions and interactions between objects and actors

" Can show

$ Current state of the work

$ Future state of the work

Usage scenarios describe in detail a particular instance of a use case Usage scenarios document the sequence of tasks It will take many usage scenarios to document a use case completely

Usage scenarios reveal objects in a workflow process Objects are something that a system affects, something that affects the system, or something that a system needs to know about to function properly In the training center example, objects include a customer, a training course, or a sales representative Objects provide a view of the characteristics and behavior of elements in the problem domain addressed by the business challenge The usage scenarios that you create during the conceptual design reveal the objects in the problem domain During the logical design, the development team will identify the objects in the usage scenarios when determining the capabilities and functionality of the solution

You can document usage scenarios in narratives, pseudocode, and task sequence diagrams Usage scenarios can also be prototyped for verification with users The following table shows one way to document a usage scenario

Slide Objective

To explain what usage

scenarios are and provide

examples