CS4/542- Software Engineering

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CS4/542- Software Engineering

• Software Design and Development
• Required Text -- Code Complete by Steve
  McConnell
• (Focuses on the problems of designing programs
  that WORK!)
• Recommended Text -- UML Distilled Second
  Edition by Martin Fowler

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Software Engineering

• CSE 4/542A
• Lec MWF 200-250, 4 Knox
• A1 F 1100-1150, 216 NSC
• A2 R 1530-1620, 322 Clemens
• Recitations meet irregularly, they are team
  meeting times.
• TA -- Joshua Kershner

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Helene G. Kershner

• Assistant Chairman
• Office 209 Bell Hall
• Office Hours
• To be determined
• By Appointment
• Login name kershner_at_cse.buffalo.edu

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Course Environment

• CSE4/542 is a Team-based course.
• Real-world simulation
• Real project for a Customer
• Writing course
• Programming course

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Requirements

• Programming Languages Experience designing
  Algorithms
• Senior/Graduate Course
• Consider yourself -- Computer Professionals
• Effective Communicator
• Consider yourself an experienced Programmer

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(No Transcript)
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Software Design andDevelopment

• better known as
• Software Engineering

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Software Engineering

• The body of theory and practical techniques
  involved in the process of developing large scale
  software

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Why Software Engineering (SE)? To Answer these

• Why does it take so long to get programs
  finished?
• Why are costs so HIGH?
• Why cant we find all the errors before we
  release software to our customers?
• Why do we have such difficulty measuring progress
  as software is being developed?

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Software is like Entropy,

• It is difficult to grasp, weighs nothing and
  obeys the Second Law of Thermodynamics
• i.e., It ALWAYS increases.

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Programming is

• " a young person's skill. It requires intense
  concentration. To do a good job, you have to
  have your mind wrapped around the whole program.
  It's very easy to get distracted. You do things
  and forget about other things and end up with
  bugs. It's like running a marathon. You have to
  be constantly focused on the goal." NY Times

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We do more than PROGRAM!

• We DESIGN and DEVELOP software to solve problems.

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Writing Software (Design)

• " is figuring out the real problem people are
  trying to solve and the best way to solve the
  problem, which is not always the way they
  suggest."

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Software Design

• Software Development is Technology in Crisis!
• Writing Large-Scale Software is Problematic!

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The Central Debate

• Is the creation of software
• an art,
• a science, or
• a discipline ???

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What is Software Engineering? In 1969 NATO
Conference

• "the establishment and use of sound engineering
  principles in order to economically obtain
  software that is reliable and works efficiently
  on real machines."

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What is Software Engineering?

• "fabrication that takes away the uniqueness and
  magic of programming."

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Designing software is difficult.

• The larger the project, the more difficult the
  solution.

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What is Software Engineering?

• Software Engineering is "the systematic approach
  to the development, operation, maintenance, and
  retirement of software." IEEE Glossary
• Software is " computer programs, procedures,
  rules and possibly associated documentation and
  data pertaining to the operation of a computer
  system."

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What is Software Engineering?

• Software Engineering is " the technological and
  managerial discipline concerned with systematic
  production and maintenance of software products
  that are developed on time and within cost
  estimates."(Fairley)

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There is a crisis in Technology!

• 1) How does one design large-scale
  software?
• 2) We have an Aging Software Plant.

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Aging Software

• Across the nation, and the world, software is
  AGING!
• AND-- Little is done to rewrite and redesign the
  software!
• Why?

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Why?

• " The application STILL works?"
• "It is not 'economical' to commit the resources
  to make them better!"

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Software doesn't wear out! ????

• Is this true???

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What is the Software Crisis?

• What does it "look like"?

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Software Crisis?

• Hardware sophistication has outpaced our ability
  to build software that can tap hardware's
  potential.
• Our ability to build new programs cannot keep
  pace with the demand for new programs.
• Our ability to maintain existing programs is
  threatened by poor design and inadequate
  resources.

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Software Crisis?

• Our inability to complete current work on time
  and within budget -- means -- needed
  maintenance and new development efforts pile up.
• Our techniques for managing software development
  projects are usually inadequate. Products are
  often late, inefficient, expensive, or
  unsatisfactory to users.

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Software Crisis?

• Some believe
• Programmers cannot even begin to use the tools
  that are available
• Programmers cannot be trusted to test their own
  programs adequately

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Why Software Engineering?

• Why does it take so long to get programs
  finished?
• Why are costs so high?
• Why can't we find all errors before we give the
  software to our customers?
• Why do we have difficulty in measuring progress
  as software is being developed?

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The primary challenge of the new century will be
to improve the quality of computer-based
solutions, while simultaneously reducing the time
required to createthem.

• - these solutions are those implemented with
  software!