18 March

1
18 March

• Implementation

2
Tools

• Do you need them?
• When do you need them?
• What can they do better then you?

3
Tools

• Version Management
• Build Systems
• Integrated Development Environments
• Documentation Extraction

4
Version Management

• Both during and after development
• Both code and documentation
• Uses
• Multi-developer change control
• Releases
• Support for different environments
• Computers
• Operating systems

5
Top Reasons for Using Version Management

• Bugs which were fixed reappear
• Latest versions of code overwritten by old
  versions
• Which version is the right one? I have so many
• I have lost my latest changes

6
Questions Addressed

• Development Issues
• How do we integrate parallel work?
• How do I know which changes were in the code that
  was being tested?
• Who changed this module? When? Why?
• Multi-version Issues
• What versions have been made available to people?
• How do I assure that all versions get the changes
  that they need?
• What versions need to be re-released to support
  changes made?

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Documentation that Needs Version Control

• Manuals need to reflect the variations of the
  different releases
• Test data what tests have been run and what was
  the result
• Bug reports
• Planned changes
• Any document being edited by multiple people

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Basic Functions

• Ability to add and remove changes
• Ability to identify differences
• Record of changes made
• Storage of different versions
• Ability to get access to one or more versions
• Identification of all the components needed to
  build any version

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Need a Baseline

• Agreed upon document or code level
• in large project, formally reviewed and agreed
  upon
• in your project, requires consensus agreement
• Basis for further development
• in large project, changed only through formal
  change control procedure
• In your project, changed when the developer is
  comfortable

10
When To Start Using Version Control

• Should you use it during unit testing?
• What is unit testing?
• How much structure does your unit testing
  require?
• If unit testing requires significant
  infrastructure or scaffolding, it makes sense to
  start using it very early

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No Special Tools Needed

• Identify procedures and data needed to
• add and remove changes
• identify differences
• record changes made
• store different versions
• get access to one or more versions
• build any version

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But there are tools

• CVS Concurrent Version System
• Subversion (SVN)
• SourceForge
• Actually uses CVS and SVN, but a different model

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Concurrent Versioning System

• Developed in the mid 80s
• Predecessor RCS (Revision Control System)
• Vrije University, Amsterdam
• Now open source
• Until recently, the most commonly used tool
• ximbiot.com/cvs/wiki

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What CVS Does

• Supports hierarchical directories
• manages changes on a per file basis
• Remote repository access
• import locally for use
• Supports parallel development
• merges changes
• identifies, does not resolve, conflicts
• Basic tasks
• getting a working copy
• committing changes
• reverting to prior level
• adding or removing a file
• synchronizing to the latest code
• tagging versions of files

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Subversion

• http//subversion.tigris.org/
• improved version of CVS
• consistent interfaces except for compelling
  reasons
• key changes
• everything is versioned directories and file
  meta-data as well as files
• atomic commits
• guarantee that all aspects are completed or none
  are
• better performance

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SourceForge

• Open source development environment
• Free web-based facility
• Purchasable software as well
• SourceForge.net supports
• CVS and SVN
• Compile farm
• Trackers
• Web site

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Lots of Others

• Google code
• TRAC

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Tools

• Version Management
• Build Systems
• Integrated Development Environments
• Document Extraction

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Build System Functions

• System configuration
• Executing
• preprocessors
• compilers
• linkers
• Manage paths and libraries
• Create executables and libraries

20
Types of Build Systems

• Platform
• specific
• independent
• Part of
• version management systems
• integrated development environments
• nothing (standalone)

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Platform Specific System Unix make

• Uses a makefile
• Can build full systems or parts
• Defines dependencies
• Simplest example object file depends on its
  source file
• Executes commands for any (and only) pieces that
  need to be rebuilt

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Open Source SystemsLots of Them

• GNU make
• Been around for a while
• Cons
• Built in Perl
• SCons
• Python scripts
• CMake
• cross-platform
• used in conjunction with the native build
  environment
• Jam
• C and C
• See also FT Jam (additional platforms)

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Apache Ant build

• http//ant.apache.org
• Introduction
• Workflow elements
• XML-based configuration files
• Java based
• contains features specifically for J2EE

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Ant Control Commands (sample)

• Ant Runs Ant on a supplied buildfile
• AntCall Runs another target within the same
  buildfile
• Exec Executes a system command (can be OS
  specific)
• Java Executes a Java class
• Parallel Forks a new thread for another Ant
  tasks
• Sequential Grouping of commands
• Waitfor Blocks execution until a set of
  specified conditions become true

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Tools

• Version Management
• Build Systems
• Integrated Development Environments
• Document Extraction

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Integrated Development Environment

• What is an IDE?
• A programming environment integrated into a
  software application
• Normally includes
• Source code editor
• Compiler and or interpreter
• GUI development tools
• Build system
• May also include
• Graphical tools (e.g., class hierarchy diagram)
• Debugger
• Class browser
• Version management system

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History

• Early programming was not done with IDEs
• Coding sheets and keypunches
• Line command make files
• Hardware enhancements
• typewriter-like terminals
• computer screens
• Which of these enabled IDEs? Why?

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Dartmouth Time Sharing System (1964)

• Command line system
• Supported Basic, Algol and FORTRAN
• DTSS commands
• NEW, OLD, LIST, SAVE, RUN
• Line starting with number replaced that line in
  the current program
• All other commands implied execution
• Considered by most people the first IDE

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Todays IDEs

• Menu-driven
• Proprietary
• Microsoft Visual Studio (C, C, Visual BASIC)
• Borland JBuilder (Java)
• Apple XCode (Mac OS X)
• Open Source
• SharpDevelop (.NET)
• GNU Emacs (Unix) major modes for languages

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Eclipse

• www.eclipse.org
• Both an IDE and an architecture
• IDEs
• Java, C, C, C, Python, PHP, Perl, Smalltalk,
  CMFL (Coldfusion), Cobol, Fortran, Prolog, Erlang
• (you get the idea)
• IDE built using architecture
• Enhancements through plug-ins

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Tools

• Version Management
• Build Systems
• Integrated Development Environments
• Documentation Extraction

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What can be extracted?

• Documentation
• Signatures
• Building interfaces first
• Initial documentation
• Tools avoid update issues
• Are there drawbacks?

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Tools

• Doxygen open source
• Javadoc from Sun

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Software Engineering Elaborated Steps

• Concept
• Requirements
• Architecture
• Design
• Implementation
• Unit test
• Integration
• System test
• Maintenance

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Models of Software Development

• Process or people oriented
• Early Watts Humphrey work people, later process
• Different balances from each model
• Number of iterations
• Waterfall
• Spiral
• Agile

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Software Craftmanship

• Software craftsmanship (McBreen 2001)
• Craft of writing software
• Craft of using software
• Distinguish from software engineering
• Scope
• Rigor
• Relevant distinction?