Software Engineering

1
Software Engineering

• Textbook Software Engineering -- A
  Practitioners Approach, 5th Edition by Roger
  S. Pressman
• URL http//dslab.kunsan.ac.kr/softeng.htm
• http//bobby-gerardo.tripod.com/softeng

2
Software Engineering

• Course Outline
• Part 1 -- The Product and the Process
• Chapters 1 2
• Part 2 -- Software Management
• Management Concepts -- Chapter 3
• Software Process and Project Metrics -- Chapter 4
• Project Planning -- Chapter 5
• Risk Management -- Chapter 6
• Scheduling and Tracking -- Chapter 7
• Quality Assurance -- Chapter 8
• Configuration Management -- Chapter 9

3
Software Engineering

• Course Outline
• Part 3 -- Conventional Methods
• System Engineering - Chapter 10
• Analysis Concepts and Principles - Chapter 11
• Analysis Modeling - Chapter 12
• Design Concepts and Principles - Chapter 13
• Design Methods - Chapter 14
• Real-Time Design - Chapter 15
• Testing Methods and Strategies - Chapter 16 17
• Metrics for Software - Chapter 18

4
Software Engineering

• Course Outline
• Part 4 -- Object-Oriented SE
• Object-Oriented Concepts - Chapter 19
• Object-Oriented Analysis - Chapter 20
• Object-Oriented Design - Chapter 21
• Object-Oriented Testing - Chapter 22
• Metrics for Object-Oriented Systems - Chapter 23

5
Software Engineering

• Course Outline
• Re-ordered topics -- Testing
• Testing Methods and Strategies - Chapter 16 17
• Object-Oriented Testing - Chapter 22

6
Software Engineering

• Course Outline
• Part 5 -- Advanced Topics
• Formal Methods -- Chapter 24
• Cleanroom SE -- Chapter 25
• Software Reuse -- Chapter 26
• Re-engineering -- Chapter 27
• Client/Server -- Chapter 28
• Computer-Aided Software Engineering -- Ch. 29
• The Future -- Chapter 30

7
Software Engineering

• An initial calibration of perspective

• How many lines of code are produced, on average,
  by one software engineer in a year?

• How long would it take you to do the attached web
  generation problem?

• How long would it take you to do the attached web
  generation problem?

8
Software Engineering Introduction

• What is Software Engineering (SE)?

• The process of building a software product.

• Some questions to put SE in perspective

• What are the sizes of some typical software
  products?

• Maple.exe 1.3 Mbytes.-- System over 3.8 Mbytes

• Netscape.exe 1.26 megabytes.

• Microsoft Office XP gt 300 megabytes.

• How many people would it take to build these in 1
  year? 2?

• What would you do if a bug could cost lives and
  2 billion?

• What would you do if a delay could cost 100s of
  millions?

9
Software Engineering Introduction

• Some questions to put SE in perspective (cont)

• What is the impact of distributing buggy software?

• Why do we have so many software upgrades?

• What is the impact of software upgrades?

• What are some of the ethical issues in software
  development?

• Why is it so difficult to measure software
  development progress?

• Why does it take so long to develop software?

• Why does software cost so much?

• Why do people continue to use buggy and/or
  obsolete software?

10
Some Software Characteristics

• Software is engineered or developed, not
  manufactured in the traditional sense.

• Software does not wear out in the same sense as
  hardware.

11
Some Software Characteristics

• In theory, software does not wear out at all.

• BUT,

• Hardware upgrades.

• Software upgrades.

12
Some Software Characteristics

• Thus, reality is more like this.

• Most serious corporations control and constrain
  changes

• Most software is custom built, and customer never
  really knows what she/he wants.

13
Some General Approaches

• Develop and use good engineering practices for
  building software.

• Make heavy use of reusable software components.

• Use modern languages that support good software
  development practices, e.g., C, C, Java.

• Use 4th generation languages.

• But, almost everything is a two-edged sword.

• Consider long term tool maintenance.

• Right now, this is a major problem for NASA.

14
Types of Software Applications

• Systems Software

• Real-Time Software

• Business Software

• Engineering Software

• Embedded Software

• Artificial Intelligence Software

• Personal Computer Software

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16
Software Myths

• Myth Its in the software. So, we can easily
  change it.

• Reality Requirements changes are a major cause
  of software degradation.

• Myth We can solve schedule problems by adding
  more programmers.

• Reality Maybe. It increases coordination
  efforts and may slow things down.

• Myth While we dont have all requirements in
  writing yet, we know what we want and can start
  writing code.

• Reality Incomplete up-front definition is the
  major cause of software project failures.

17
Software Myths

• Myth Writing code is the major part of creating
  a software product.

• Reality Coding may be as little as 10 of the
  effort, and 50 - 70 may occur after delivery.

18
Software Myths

• Myth I cant tell you how well we are doing
  until I get parts of it running.

• Reality Formal reviews of various types both can
  give good information and are critical to success
  in large projects.
• Myth The only deliverable that matters is
  working code.

• Reality Documentation, test history, and program
  configuration are critical parts of the delivery.

• Myth I am a (super) programmer. Let me program
  it, and I will get it done.

• Reality A sign of immaturity. A formula for
  failure. Software projects are done by teams,
  not individuals, and success requires much more
  than just coding.