18 March Implementation

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

Tools Version Management Build Systems Integrated Development Environments Documentation Extraction

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

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

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?

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

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

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”

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

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

But there are tools … CVS: Concurrent Version System Subversion (SVN) SourceForge Actually uses CVS and SVN, but a different model

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

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

Subversion 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

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

Lots of Others Google code TRAC

Tools Version Management Build Systems Integrated Development Environments Document Extraction

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

Types of Build Systems Platform specific independent Part of version management systems integrated development environments nothing (standalone)

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

Open Source Systems: Lots 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)FT Jam

Apache Ant: build Introduction Workflow elements XML-based configuration files Java based contains features specifically for J2EE

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

Tools Version Management Build Systems Integrated Development Environments Document Extraction

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

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?

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

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

Eclipse 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

Tools Version Management Build Systems Integrated Development Environments Documentation Extraction

What can be extracted? Documentation Signatures Building interfaces first Initial documentation Tools avoid update issues Are there drawbacks?

Tools Doxygen – open source Doxygen Javadoc – from Sun Javadoc

Software Engineering Elaborated Steps Concept Requirements Architecture Design Implementation Unit test Integration System test Maintenance

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

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