Unit 19 Object Oriented Programming

·   Aim

To provide learners with an understanding of the principles of object oriented programming as an underpinning technological concept in the field of programming, data management and systems development.

·   Unit abstract

Object oriented programming is an industry-proven method for developing reliable modular programs and is popular in software engineering and systems development. Consistent use of object oriented techniques can lead to shorter development life cycles, increased productivity, adaptable code, reuse of different technologies, the interaction of different systems using common platforms and therefore lower the cost of producing and maintaining systems.

The development of systems with objects simplifies the task of creating and maintaining complex applications. Object oriented programming is a way of modelling software that maps programming code to the real world.

In terms of impact, object oriented technology can be found in many systems, from commercial operating systems to mobile phones and in many multimedia applications. The majority of programming languages are object oriented in focus, with the exceptions preferring to offer specialist programming resources. It is dominant in Visual Studio, C++, Java, the Microsoft

.Net environment, Action Script and many other systems.

Learners taking this unit will have the opportunity to develop their understanding of the object oriented paradigm and develop code suited to a range of platforms using the object oriented methodology.

·   Learning outcomes

On successful completion of this unit a learner will:

1. Understand the principles of object oriented programming
2. Be able to design object oriented programming solutions
3. Be able to implement object oriented programming solutions
4. Be able to test and document object oriented programming solutions.

Unit content

1         Understand the principles of object oriented programming

Characteristics of objects: types eg constructors, destructors; classification; features eg inheritance, polymorphism, encapsulation, public classes, private classes, public methods, private methods, message passing; interpreted, open source, common libraries

Variables: public instance variables; private instance variables; static references

Software engineering: features eg modularity, encapsulation, reuse, method overloading, instance variables, classes, abstract classes, interfaces

Classes: characteristics eg identification attributes, control of scope of attributes and methods, inheritance, aggregation, association, polymorphism

2         Be able to design object oriented programming solutions

Development: selection eg identification of programming language, identification of programming libraries, selection of development environment

Design methodology: options eg reuse of existing system, adaptation of code, use of open source

Design method: tools eg class responsibilities collaboration cards, class diagram, identification of dependencies and inheritances, data and file structures.

System delivery: style eg scripted, interpreted, compiled

Programming platform: types eg GUI, script, command line

Delivery environment: types eg mobile, handheld, web based, desktop, dedicated device

Interaction: considerations eg exchange of data with other systems, compliance, compatibility, recognition of standards employed

Design refinement: clarification of a design using principles of maximum coherence and minimum coupling between the classes

3         Be able to implement object oriented programming solutions

Coding: use of conventional language commands; pre-defined eg class library, downloaded, imported, reversion code

Control structures: types eg subroutines, branching, iteration, interrupts, signals

Complexity: inclusion of eg multiple classes, application of inheritance in created code, reuse of objects

IDE: typical elements eg source code editor, compiler, interpreter, build automation tools, debugger

4         Be able to test and document object oriented programming solutions

Testing: mechanisms eg valid declarations, debugging code, comment code, naming conventions, checking functionality against requirements; documentation

Errors: handling eg management of extremes, use of system imposed statements Impact testing: types eg range testing, input testing, load testing, system compatibility Onscreen help: methods eg pop-ups, help menu, hot-spots

Documentation: technical documentation to include eg designs, delivery system, platform, environment, file structures, coding, constraints, maintenance requirements

Learning outcomes and assessment criteria

Learning outcomes   On successful completion of this unit a learner will:	Assessment criteria for pass   The learner can:
LO1 Understand the principles of object oriented programming	1.1 discuss the principles, characteristics and features of objected oriented programming
LO2 Be able to design object oriented programming solutions	identify the objects and data and file structures required to implement a given designdesign an object oriented programming solution to a given problem
LO3 Be able to implement object oriented programming solutions	implement an objected oriented solution based on a prepared designdefine relationships between objects to implement design requirementsimplement object behaviours using control structures to meet the design algorithmsmake effective use of an Integrated Development Environment (IDE), including code and screen templates
LO4 Be able to test and document object oriented programming solutions	critically review and test an object orientated programming solutionanalyse actual test results against expected results to identify discrepanciesevaluate independent feedback on a developed object oriented programme solution and make recommendations for improvementscreate onscreen help to assist the users of a computer programcreate documentation for the support and maintenance of a computer program.

Guidance

Links to National Occupational Standards, other BTEC units, other BTEC qualifications and other relevant units and qualifications

The learning outcomes associated with this unit are closely linked with:

Level 3	Level 4	Level 5
Unit 6: Software Design and Development	Unit 18: Procedural Programming	Unit 35: Web Applications Development
Unit 14: Event Driven Programming	Unit 20: Event Driven Programming Solutions	Unit 39: Computer Games Design Development
Unit 15: Object Oriented Programming	Unit 21: Software Applications Testing	Unit 40: Distributed Software Applications
Unit 16: Procedural Programming	Unit 22: Office Solutions Development	Unit 41: Programming in Java
	Unit 23: Mathematics for Software Development	Unit 42: Programming in .NET

This unit has links to the Level 4 and Level 5 National Occupational Standards for IT and Telecoms Professionals, particularly the areas of competence of:

• Software Development.