Chapter 2 The software development process

The software
Development Process
Chapter 2

Highlights
What major components go into a software
Product
What different people and skills contribute
A Software Product
How software progresses from an idea to
Final Product

What efforts goes into a software
Product
Product
Product
Specification
Product
Reviews
Design
Document
Schedules feedback competitive
Information
Test Plan customer surveys Usability Data
Look and Feel software code
Software
Architecture

Customer requirements
Collect detailed information in the form
Surveys
Feedback
Competitive product information
Magazine reviews
Focus groups
Etc.

Specification
The result of the customer requirements
Studies is really just raw data
Especially
Government
Aerospace
Financial
Medical Industries

Schedules
Some mechanisms to track the software's
SS
Simple task list
Gantt Chart
Goal of scheduling
Know which work has been completed
How much work is still left
When it will all be finished

Software deign documents
Architecture
Data Flow digoal
State Transition Divisor
Flowchart
Commented code

Test Documents
Test Plan
Quality Objectives, resource needs, schedules,
Assignments, methods, etc.
Test Cases
Specific items and detailed steps
Bug reports
Problem Found
Test Tools and automation
Metrics, statistics, and summaries

What parts make up a software
Product

Software Project Staff
Project Manager
Writing spec, managing schedule, and making
Critical decisions and trade-offs
Effecect
Design the overall systems architecture
Programmers
Write software and fix the bugs
Tester or QA
Finding and reporting problems
Technical writers
Create paper and online documentation
Configuration Management
Pulling together the software and all the documentation

Software development lifecycle
Models
"Three things that never be seen in the Process
Being created: laws, sausage, and software"
Software development lifecycle
The process used to create a software product from its
Initial conception to its public release
Classical Models
Big-bang
Code-and-fix
Waterfall
Spiral

Big-bang model
Beauty of big-bang is that it's simple
There is little to no formal testing done
Testing become both an easy and a difficult task
Boom
B o m
Final Product
?

Code-and-fix Model
Usually the project teams fall into by default
"There's never time to do it right, but there's always
Time to do it over"
Well for small project such as prototypes and demos
Good introduction to software development, and help
You appriaciate the more formal methods
Informal Product
Specification
Code, fix and
Repeat?

Waterfall Model
Simple, elegant and make senses
Ideaanalysisdesigndevelopmenttestfinal
Product
At the end of each step, a review is held
Three important things
There's large emphasis on specifying what the product
Will be
Discrete, no overlap
No way to back up
However, requirement is fast changing
A fundamental problem cocould creep in early on and
Not be detected until days before product release

Spiral Model
Start small
Each spiral involves six steps
Determine objectives, alternatives and
Constraints
Identify and resolve risks
Evaluate Alternatives
Develop and test the current level
Plan the next level
Decide on the approach for the next level
Been testing all along

New trends
Uniied Process
Agile Software Development
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