Oose_week 1- Software Construction

8/15/2019 Oose_week 1- Software Construction

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Software Construction 1

SOFTWARE CONSTRUCTION

LECTURE 1


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Books (Reference Material )

• Applying UML and Patterns: An Introduction to Object-Oriented Analysis andDesign and Iterative Development

Author(s) Craig Larman

Publisher: Prentice Hall; 3 edition

• Code Complete - A Practical Handbook of Software Construction (2nd

Edition) [Steve McConnell] (2004)

• Object-Oriented Software Construction, by Bertrand Meyer, Second Edition,Published by, Prentice Hall in 1997



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Grading Criteria

20% Mid Term

20% Quiz and Assignments

20 % Lab !ro"ect

#0% $ina &'am


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4

Software Processes

• A Software Process is

•A set of activities (e.g. requirements, analysis, design,coding, testing) combined and sequenced in a particularfashion to produce software

• Recent trend: Agile Software Development

•Customer needs evolve with time

•Satisfying customers at delivery time (rather than atproject initiation) is more important than conforming to

initial customer requirements

Software Construction #


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5

Software Development Phases

RequirementsRequirementsWhat needs to be doneWhat needs to be done

RequirementsRequirementsWhat needs to be doneWhat needs to be done

AnalysisAnalysisHow it should be doneHow it should be done

AnalysisAnalysisHow it should be doneHow it should be done

DesignDesignCreate a software structureCreate a software structure(architecture) around which(architecture) around whichcode will be builtcode will be built

DesignDesignCreate a software structureCreate a software structure(architecture) around which(architecture) around whichcode will be builtcode will be built

CodingCodingFill in the softwareFill in the softwarestructure with codestructure with code

CodingCodingFill in the softwareFill in the softwarestructure with codestructure with code

TestingTestingCheck that the code does whatCheck that the code does what

it is supposed to (functionality,it is supposed to (functionality, performance, reliability, …) performance, reliability, …)

TestingTestingCheck that the code does whatCheck that the code does what

it is supposed to (functionality,it is supposed to (functionality, performance, reliability, …) performance, reliability, …)

Project ManagementProject ManagementDevise a plan,Devise a plan, manaemanaeresources, costs, time, …resources, costs, time, …

Project ManagementProject ManagementDevise a plan,Devise a plan, manaemanaeresources, costs, time, …resources, costs, time, …

Software Construction (


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6

Software Phases Related to this

Course

DesignDesign

Create a software structureCreate a software structure

(architecture) around which(architecture) around which

code will be builtcode will be built

DesignDesign

Create a software structureCreate a software structure

(architecture) around which(architecture) around which

code will be builtcode will be built

CodingCodingFill in the softwareFill in the software

structure with codestructure with code

CodingCodingFill in the softwareFill in the software

structure with codestructure with code

Software Construction )


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Software Construction *

Introduction

Definition of Software Construction:

Detailed creation of working, meaningful software through acombination of coding, verification, unit testing,integration testing, and debugging

Software construction closely tied to

•Software design•Software testing

Design

Construction

Testing


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Software Construction +

Introduction - 2

More on Construction

• Significant detailed design occurs during construction• Low-level (e.g. unit and module integration) testing occursduring construction

• Construction produces high volume of configuration items

• Thus construction linked to configuration management

• Construction is tool intensive

• Quality is very evident in the construction products

• Construction highly related to Computer Science due to

• Use of algorithms

• Detailed coding practices


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Software Construction ,

Introduction - 3

Software Construction Fundamentals

The fundamentals of software construction include:•Minimizing complexity

•Anticipating change

•Constructing for verification

•Standards in construction


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Introduction - 4

Minimizing Complexity

• Humans are severely limited in our ability to hold complexinformation in our working memories

• As a result, minimizing complexity is one the of strongest

drivers in software construction

• Need to reduce complexity throughout the lifecycle

• As functionality increases, so does complexity

• Accomplished through use of standards

• Examples:

•UML for modeling all aspects of complex systems

•High-order programming languages such as C++ andJava

•Source code formatting rules to aid readability


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Introduction - 5

Anticipating Change

• Software changes over time• Anticipation / hope of change affect how software isconstructed

• This can effect

•Use of control structures

•Handling of errors

•Source code organization

•Code documentation

•Coding standards


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Introduction - 6

Constructing for Verification

Construct software that allows bugs to be easily found and fixed

Examples:

• Enforce coding standards

•Helps support code reviews

• Unit testing

• Organizing code to support automated testing

• Restricted use of complex or hard-to-understand language

structures


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Introduction - 7

Standards in Construction

Standards which directly affect construction issues include:• Programming languages

• E.g. standards for languages like Java and C++

• Communication methods

•E.g. standards for document formats and contents

• Platforms

•E.g. programmer interface standards for operating

system calls, J2EE

• Tools

•E.g. diagrammatic standards for notations like the UnifiedModeling Language


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Software Construction 1#

References

• [IE04] IEEE Computer Society,Guide to the Software

Engineering Body of Knowledge (SWEBOK), IEEE ComputerSociety Press, Los Alamitos, CA 20001, June 2004

• link :


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Software Construction 1(

A. Construction Planning

• What is Construction Planning?

Laying out the work plan (i.e. schedule) to design,implement, debug, and unit test the software

• Construction planning major concerns:

•Coders are typically not planners

•Schedules will be difficult to maintain unless a good

architecture design is in place•Many organizations do not collect project data on which

to plan future projects

•Many managers consider planning to be a waste of time

and therefore don’t encourage it

•Project plans may be limited to the construction plans•Many organizations and projects do not use systematiccost estimating methods such as models


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Software Construction 1)

A. Construction Planning - 2

Improving Software Economics

• Consider reducing development costs by planning to:• Reduce the size and/or complexity

• Improve the development process

• Use more highly skilled people and build better teams

• Use better tools

• Some actions include

• Use an object-oriented approach

• Use COTS components

• Use an iterative approach

• Provide training to development team

• Automate tedious tasks with tools


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Software Construction 1*


Construction Prerequisites

• As with building construction, much of the success or failureof the project already determined before construction begins

• Upstream activities such as project planning, requirements,

architecture, and design are crucial to success

• Typical high-risk areas

•Project planning•Requirements

•Architecture

• Preparation is a way to reduce these risks


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Software Construction 1+


Problem Definition Prerequisite

• The problem being solved via the application must be welldefined

• Common names for the document containing the problem

statement:

•Product Vision

•Vision Statement•Product Definition

• Defines the problem without reference to potential solutions

• Helps avoid solving the wrong problem!


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Software Construction1,


Requirements Prerequisite

• Requirements describe in detail what a system is supposedto do, therefore are invaluable for construction

• Explicit requirements:

•Help ensure the user drives system functionality

•Rather than the programmer

•Reduce the number of construction debates

•Help minimize changes after development begins

• Specifying requirements adequately (sufficiently) is a key toproject success


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Architecture Prerequisite

• Quality of the architecture determines the conceptualintegrity of the system

• A proper architecture:

•Gives structure to maintain conceptual integrity

•Provides guidance to programmers

•Partitions work

• Architecture-level problems are much more costly to fix than

are coding errors

• Good architecture can make construction easy

•Bad architecture makes construction difficult


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Regarding Upstream Prerequisites

• Time budgeted for requirements and architecture work•10 to 20 percent of manpower

•20 to 30 percent of schedule

• If requirements are unstable

•Do not ignore, spend time to fix

•The analyst should fix if a formal project

•Can be fixed by the programmer for informal projects

• Use same heuristics for problems with the architecture


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Choose an Approach

• Many software development approaches have been triedover the years

• Some examples:

•Functional

•Object-Oriented

•Iterative•Waterfall

•Agile

• The construction team must follow some approach

• Chosen approach must be appropriate for the task at hand


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Choose a Programming Language

• Programming language choices affect•Productivity

•Code quality

• Programmers more productive using a familiar language

• High-level languages provided higher quality and better

productivity

• Some languages better at expressing programming concepts

than others

• The ways in which a programmers express themselves areaffected by the chosen language


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Software Construction 2(


Choose Tools

Modern programming tools•Are essential to maintain programmer productivity

•Reduce tedious and redundant tasks

•Must be appropriate for the task at hand

Tools preparation checklist:

• Are all product licenses current?• Are all products at current, supported revision level?

• Have all programmers received proper training on the tools?

• Does the project have a configuration management tool?

• Does the project have a tool to track change requests?

• Do project team members have sufficient workstations?• Does the project have sufficient test environments?

• Does the project have sufficient build environments?


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Software Construction 2)


Construct the Team

• For small development efforts•Self managed

•Everyone is a peer

• For mid-size development efforts

•Single team

• For large development efforts

•Multiple teams

Role # / Team*

Lead 1

Detailed designer 1 to 4

Coder 5 to 10

Integrator 1 to 2

Unit tester Same as coder

System tester 1

“Buildmeister” 1

Configuration manager 1

* Individuals will play multiple roles

Table 1: Team Composition


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Software Construction 2*

A. References

• [IE04] IEEE Computer Society,Guide to the Software

Engineering Body of Knowledge (SWEBOK), IEEE ComputerSociety Press, Los Alamitos, CA 20001, June 2004

• [RS04] IBM Rational Software, The Rational Unified

Process v2003.06.13, 2004

• [RT03]

• [SM04] S. McConnell,Code Complete: A PracticalHandbook of Software Construction, Second Edition,Microsoft Press, 2004.

• [WR01] Walker Royce,Software Project Management, AUnified Framework, Addison-Wesley, Boston, MA, 2001

Oose_week 1- Software Construction

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