CS251 Intermediate Software Design

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CS251Intermediate Software Design
Dr. Douglas C. Schmidt d.schmidt_at_vanderbilt.edu ww
w.dre.vanderbilt.edu/schmidt/cs251/
Professor of EECS Vanderbilt University
Nashville, Tennessee
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CS 251 Course Philosophy
Good design and programming is not learned by
generalities, but by seeing how significant
programs can be made clean, easy to read, easy to
maintain and modify, human-engineered, efficient,
and reliable, by the application of good design
and programming practices. Careful study and
imitation of good designs and programs
significantly improves development skills. -
Kernighan and Plauger
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CS 251 Course Information

• Required textbooks

• CS 251 class web page
• www.dre.vanderbilt.edu/ schmidt/cs251/
• My office hours in Featheringill Hall room 226
  are
• Mon Wed from 100pm to 3pm
• TAs Krzysztof Zienkiewicz William Chappell
• krzysztof.k.zienkiewicz_at_Vanderbilt.Edu
  william.t.chappell_at_Vanderbilt.Edu
• TA office hours are on the CS 251 web page
• Please send all questions to d.schmidt_at_vanderbilt.
  edu
• Ill send the answers to the class mailing list

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CS 251 Ground Rules

• Assignments must be submitted on time
• Work must be your own
• No laptops open in class during lecture or
  quizzes
• You will be called upon periodically to answer
  questions
• Youll get out of this course what you put into
  it, so be prepared to work hard
• Be prepared for weekly quizzes occasional guest
  lectures
• Make sure to avail yourself of available help,
  e.g., office hours, TAs, mailing list, etc.

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CS 251 Course Contents

• Focus on topics important to developing
  maintaining quality software
• Reuse of patterns software components
• Developing, documenting, testing, applying
  reusable classes object-oriented frameworks
  using C
• Patterns will be taught to provide good role
  models for software designs to clearly
  articulate design tradeoffs
• Object-oriented techniques will be taught to show
  how to build software architectures that decouple
  inter-dependencies between components
• I assume you know C a little bit, e.g., you
  know how to use a C compiler

• The course will cover object-oriented techniques
  that address
• Decentralized software architecture
• Architectural and design patterns
• Class interface definition
• Component reuse
• Module decomposition
• Hierarchical classification
• Extensible object-oriented application frameworks
  
• Many case studies will be used in class to
  illustrate the OO design programming process

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CS 251 Course Work

• There will be 5-6 programming assignments written
  in C
• Can be done on Windows, Linux, Mac, etc.
• Must be done individually
• Programs will be graded as follows
• 40 execution correctness
• 30 structure (e.g., modularization, information
  hiding, etc.)
• 10 insightful programming (e.g., developing
  reusable class components, etc.)
• 10 Consistent style (e.g., capitalization,
  indenting, etc.)
• 10 appropriate commenting style

• There will be a 5 point deduction (out of a
  possible 100 points) for each day that your
  program is late
• Programs turned in later than two calendar days
  after the due date will receive a 0
• There will be weekly quizzes (starting today)
• There will be a comprehensive final exam
• The relative weighting of each portion of the
  course is
• 45 Programming projects
• 40 Quizzes
• 15 Final Exam

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Overview of C
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Overview of C
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Overview of C
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Overview of Patterns
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Overview of Pattern Languages

• Motivation
• Individual patterns pattern catalogs are
  insufficient
• Software modeling methods tools largely just
  illustrate how not why systems are designed

• Benefits of Pattern Languages
• Define a vocabulary for talking about software
  development problems
• Provide a process for the orderly resolution of
  these problems, eg
• What are key problems to be resolved in what
  order
• What alternatives exist for resolving a given
  problem
• How should mutual dependencies between the
  problems be handled
• How to resolve each individual problem most
  effectively in its context
• Help to generate reuse software architectures

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Taxonomy of Patterns Idioms
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Overview of Frameworks
Framework Characteristics
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Comparing Class Libraries, Frameworks,
Components
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Overview of the ACE Frameworks

• Features
• Open-source
• 6 integrated frameworks
• 250,000 lines of C
• 40 person-years of effort
• Ported to Windows, UNIX, real-time operating
  systems
• e.g., VxWorks, pSoS, LynxOS, Chorus, QNX
• Large user community

www.cs.wustl.edu/schmidt/ACE.html
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The POSA2 Pattern Language

• Pattern Benefits
• Preserve crucial design information used by
  applications middleware frameworks components
• Facilitate reuse of proven software designs
  architectures
• Guide design choices for application developers