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Introduction to Software
Construction

Contents
? What is Software Construction
? Importance of Software Construction
? SWEBOK Guide (2004 Edition)
– Fundamentals of Software Construction
– Software Construction Management
? Key points of Software Construction

Software Construction
? Construction is the work “construction workers”
do when they build a house, a school, or a
skyscraper.
? In common usage, construction refers to the
process of building.
? The construction process might include some
aspects of planning, designing, and checking
the work, but mostly construction refers to the
hands-on part of creating something.

? Software construction is a software engineering
discipline.
? It is detailed creation of working, meaningful
software through a combination of coding,
verification, unit testing, integration testing, and
debugging.

? Following figure illustrates construction’s place
related to other software-development
activities.

? Some of the specific tasks involved in construction are:
– Verifying that the groundwork has been laid so that construction can
proceed successfully
– Determining how your code will be tested
– Designing and writing classes and routines
– Creating and naming variables and named constants
– Selecting control structures and organizing blocks of statements
– Unit testing, integration testing, and debugging your own code
– Reviewing other team members’ low-level designs and code and having
them review yours
– Polishing code by carefully formatting and commenting it
– Integrating software components that were created separately
– Tuning code to make it faster and use fewer resources

? Important non-construction activities include
– Management
– requirements development
– software architecture
– user-interface design
– system testing
– maintenance.

? Construction is also sometimes known as
“coding” or “programming.” Do you think both
these words correctly portray the term
construction?

Importance of Software Construction
? Software Construction is an important part of software
development because
– Construction is a large part of software development
– Construction is the central activity in software development
– With a focus on construction, the individual programmer’s
productivity can improve enormously
– Construction’s product, the source code, is often the only
accurate description of the software
– Construction is the only activity that’s guaranteed to be
done

SWEBOK Guide (2004 Edition)
? SWEBOK stands for Software Engineering
Body of Knowledge.
? The IEEE Computer Society has developed a
Guide to the Software Engineering Body of
Knowledge.
? The guide represents an extraction of all of the
generally accepted principles from the entire
body of knowledge.

? The Guide to the SWEBOK contains 10 knowledge areas.
– Software requirements
– Software design
– Software construction
– Software testing
– Software maintenance
– Software configuration management
– Software engineering management
– Software engineering process
– Software engineering tools and methods
– Software quality

? Software construction is a software engineering
discipline.
? It is the detailed creation of working meaningful
software through a combination of coding,
verification, unit testing, integration testing,
and debugging.
? It is linked to all the other software engineering
disciplines, most strongly to software design
and software testing.

? According to the SWEBOK CH#3, the basic
fundamentals of Software construction are
– Minimizing Complexity
– Anticipating Change
– Constructing for Verification
– Reuse
– Standards in Verification

Minimizing Complexity
? Humans are limited in their ability to hold complex structures
and information in their working memories, especially over
long periods of time.
? It proves to be a major factor influencing how people convey
intent to computers and leads to one of the strongest drives
in software construction: minimizing complexity.
? In software construction, reduced complexity is achieved
through emphasizing code creation that is simple and
readable.
? It is accomplished through making use of standards, modular
design and numerous other specific techniques

Anticipating Change
? Most software will change over time, and the
anticipation of change drives many aspects of
software construction.
? Changes in the environments in which software
operates also affect software in diverse ways.
? Anticipating change helps software engineers
build extensible software, which means they can
enhance a software product without disrupting
the underlying structure.

Anticipating Change
? Research over 25 years showed that the cost of
rework can be 10 to 100 times (5 to 10 times
for smaller projects) more expensive than
getting the requirements right the first time.
? Given that 25% of the requirements change
during development on average project, the
need to reduce the cost of rework elucidates
the need for anticipating change.

Constructing for Verification
? Constructing for verification means building software in
such a way that faults can be readily found by the
software engineers writing the software as well as by the
testers and users during independent testing and
operational activities.
? Specific techniques that support constructing for
verification include following coding standards to support
code reviews and unit testing, organizing code to support
automated testing, and restricting the use of complex or
hard-to-understand language structures, among others.

Reuse
? Reuse refers to using existing assets in solving
different problems.
? In software construction, typical assets that are
reused include libraries, modules, components, source
code, and commercial off-the-shelf (COTS) assets.
? Reuse is best practiced systematically, according to a
well-defined, repeatable process.
? Systematic reuse can enable significant software
productivity, quality, and cost improvements.

Reuse
? Reuse has two closely related facets
– construction for reuse
– construction with reuse
? The former means to create reusable software
assets, while the latter means to reuse software
assets in the construction of a new solution.
? Reuse often transcends the boundary of
projects, which means reused assets can be
constructed in other projects or organizations.

Standards in Construction
? Applying external or internal development standards during construction
helps achieve a project’s objectives for efficiency, quality, and cost.
? Choices of allowable programming language subsets and usage
standards are important aids in achieving higher security.
? Standards that directly affect construction issues include
– communication methods (for example, standards for document formats and
contents)
– programming languages (for example, language standards for languages like
Java and C++)
– coding standards (for example, standards for naming conventions, layout, and
indentation)
– platforms (for example, interface standards for operating system calls)
– tools (for example, diagrammatic standards for notations like UML (Unified
Modeling Language)).

Managing Construction
? According SWEBOK guide, software
construction is managed by following activities
– Construction Models
– Construction Planning
– Construction Management

Construction Models
? Numerous models have been created to develop software; some
emphasize construction more than others.
? Some models are more linear from the construction point of view
—such as the waterfall and staged-delivery life cycle models.
? These models treat construction as an activity that occurs only
after significant prerequisite work has been completed—including
detailed requirements work, extensive design work, and detailed
planning.
? The more linear approaches tend to emphasize the activities that
precede construction (requirements and design) and to create
more distinct separations between activities.
? In these models, the main emphasis of construction may be coding.

Construction Models
? Other models are more iterative such as
evolutionary, prototyping and agile development.
? These approaches tend to treat construction as
an activity that occurs concurrently with other
software development activities (including
requirements, design, and planning).
? These approaches tend to mix design, coding,
and testing activities, and they often treat the
combination of activities as construction.

Construction Planning
? The choice of construction method is a key
aspect of the construction-planning activity.
? The choice of construction method affects the
extent to which construction prerequisites are
performed, the order in which they are
performed, and the degree to which they
should be completed before construction
work begins.

Construction Planning
? Construction planning also defines
– the order in which components are created and
integrated
– the integration strategy
– the software quality management processes
– the allocation of task assignments to specific
software engineers according to the chosen
method.

Construction Measurement
? Numerous construction activities and artifacts
can be measured including code developed,
code modified, code reused, code destroyed,
code complexity, code inspection statistics, fault-
fix and fault-find rates, effort, and scheduling.
? These measurements can be useful for purposes
of managing construction, ensuring quality
during construction, and improving the
construction process

Practical Considerations
? Software construction is driven by many
practical considerations:
– Construction Design
– Construction Languages
– Coding
– Construction Testing
– Reuse
– Construction Quality
– Integration

Key Points
? Software construction is the central activity in
software development; construction is the only
activity that’s guaranteed to happen on every project.
? The main activities in construction are detailed design,
coding, debugging, integration, and developer testing
(unit testing and integration testing).
? Other common terms for construction are “coding”
and “programming.”
? The quality of the construction substantially affects the
quality of the software.

Readings
? [Chapter 1] Code Complete: A Practical
Handbook of Software Construction by Steve
McConnell, Microsoft Press; 2nd Edition (July
7, 2004). ISBN-10: 0735619670
? http://swebokwiki.org/
Chapter_3:_Software_Construction

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