LECTURE 1 Bushra Riaz
LECTURE 1Bushra Riaz
COURSE OUTLINECourse Code: EC-241
Credits: 4 (3,1) Prerequisites: EC-111 Algorithms and
Computing Text Book
C++ How to Program, Deitel and Deitel, 7th Edition, ISBN-10: 0-13-611726-0, Prentice Hall, 2009
References Object Oriented Programming with C++, Robert Lafore,
4th Edition, ISBN-10: 0-672-32308-7, Sams, 2002 The complete Reference C++, Herber Schildt, 3rd Edition The Unified Modeling Language User Guide, Booch,
Rumbaugh, Addison- Wesley, ISBN-10: 0-321-26797-4, 2nd Edition, 2005
COURSE OUTLINEIntroduction: Procedural versus Object Oriented
Programming (OOP), characteristics of OOP, advantages of OOP, Abstract Data Types (ADT), information hiding, encapsulation.
Classes and Objects: Classes, objects, access specifiers, data members, member functions, properties, getters and setters, object aggregation.
Constructors and Destructors: Default constructors, overloaded constructors, copy constructor, conversion constructor, shallow vs. deep copy.
COURSE OUTLINEStatic Members: Static data members and
static member functions. Generic Programming and Overloading:
Function overloading, operator overloading, templates, C++ standard template library (STL).
Dynamic memory management for objects: Pointers to objects, reference variables
COURSE OUTLINEInheritance and Polymorphism:
Inheritance, types of inheritance, derived classes, function overriding, dynamic binding, polymorphism, virtual functions.
Streams and Files: Stream classes, File objects, File operations with streams.
Object-Oriented Design: Introduction to Unified Modeling Language (UML).
Evaluation Methods:AssignmentsQuizzesMidterm exams Final Exam LabProject
PROCEDURAL VS. OBJECT-ORIENTED LANGUAGES
Procedural LanguageViews a program as a series of steps to be
carried outE.g. C, FORTRAN, Pascal
Object Oriented LanguageViews a program as a group of objects that
have certain properties and can perform certain functions
E.g. C++, Java, C#
PROCEDURAL VS. OBJECT-ORIENTED LANGUAGESProblems with Procedural Languages
Cannot cope with very large project sizesExpensive software errors (e.g. air traffic
control)Causes of Problems
Unrestricted Access to Data Global data is allowed Access to data by multiple functions means many
connections between functions Programs become difficult to understand, modify and
maintain
PROCEDURAL VS. OBJECT-ORIENTED LANGUAGES
Poor Modeling of Real World Things Real world things are integral collections of data
and functions e.g. a car: has data (make, model etc.) and
functions (acceleration) Procedural languages do not tie up data with
functions
ExampleProcedural program1. Gather ingredients
Flour, butter, egg, sugar etc2. preheat oven to 350 degree3. beat eggs and butter4. add sugar5. mix6. bake 10 mins
Example Object Oriented programingModel for an Object
Properties List of ingridients, or set of data
Methods List of actions or instructions
ExampleObject Oriented programingBaker {
Properties (ingredients) Flour Butter Eggs Milk Cake pan Oven
Methods (actions) Bake cookies Bake cake Bake pie
}
1. Gather ingredientsFlour, butter, egg, sugar etc
2. preheat oven to 350 degree3. beat eggs and butter4. add sugar5. mix6. bake 10 mins
Global Data
Global Data
Global Data
Function Function Function Function
GOAL OF OOPClearer, more reliable, more easily
maintained programsMore effective way of coping with program
complexity
OBJECT-ORIENTED LANGUAGESC++
Most widely usedLargest programmer base
JavaLacks certain features, e.g. multiple
inheritance, pointers, templatesLess powerful than C++ (but more safe, of
course)C#
Emerging
THE OO APPROACHThe fundamental idea is to combine into a
single unit both data and functions that operate on the data.
Such a unit is called an “Object”.An object’s functions are called “member
functions” in C++And its data is called “ data members”.
THE OO APPROACHAn object’s data is typically accessed through
its member functions, i.e. it is hidden from accidental alteration
Data and its function are said to be encapsulated into a single entity
Data encapsulation and data hiding are key elements of object-oriented languages
THE OO APPROACHIf you want to modify data in an object, you
know exactly what functions interact with it (i.e. the member functions of the object).
This simplifies writing, debugging, and maintaining the programs
An OO program consists of a number of objects which communicate with each other’s member functions
object
Data
Member Function
Member Function
Data
Member Function
Member Function
Data
Member Function
Member Function
objectobject
CHARACTERISTICS OF OO LANGUAGESObjectsClasses
EncapsulationInheritance Polymorphism and overloading
CLASSESObjects belong to classesA class and an object of that class has the
same relationship as a data type and a variable
All objects with the same characteristics (data and functions) constitute one class.
A class serves only as a plan, or a template, or sketch- of a number of similar things
It merely specifies what data and what functions will be included in objects of that class.
CLASSESDeclaring a class doesn’t create any objects,
just as mere existence of data type int doesn’t create any variables.
A class is thus a description of a no. of similar objects.
For instance, HUMAN is a class, and JOHN is its instance (object)
EncapsulationInformation hidingEncapsulation is the mechanism that binds
together code and the data it manipulates, and keep both safe from outside inteference and missuse
Data
Member FunctionMember Function
Data
Member FunctionMember Function
objectobject
INHERITANCEDerive other (sub-)classes from an existing
classThe original class is called the BASE CLASS;
the others are DERIVED CLASSESEach class shares common characteristics
with the class from which it was derived, and can also add its own modifications, additions.
For instance, VEHICLE is a class from which CAR, TRUCK, BUS, MOTORCYCLE classes can be derived.
Base class
Derived classes
FFeature A
FFeature B
FFeature A
FFeature B
FFeature C
FFeature A
FFeature B
FFeature D
FFeature E
FFeature A
FFeature B
FFeature F
POLYMORPHISM AND OVERLOADINGUsing operators or functions in different ways
depending on what they are operating on is called polymorphism (lit. one thing with several distinct forms)
Overloading is a special case of polymorphism, e.g. +, -, /, << etc.
C++
C
#include <iostream>
using namespace std;
int main()
{
cout<<“Every age has a language of its own\n”;
return 0;
}
PROGRAM EXPLANATION<iostream>
This header supports C++ I/O operations.iostream is to C++ what stdio.h is to C
using namespace stdThis tells the compiler to use the std name spacestd::coutThis is the namespace in which the entire Standard
C++ library is declaredThis is required when we use the names that are
brought into the program by the processor directive #include<iostream>
int main()
PROGRAM EXPLANATIONcout
An object Predefined in C++ to correspond with the
“standard output stream”
StreamAn abstraction that refers to a flow of dataThe standard output stream normally flows to the
screen
The Operator <<Directs the contents of the variable on its right to
the object on its left.
int main()
{
int ftemp;
cout<<“Enter temperature in fahrenheit: “;
cin>>ftemp;
int ctemp=(ftemp-32)*5/9;
cout<<“Equivalent in celsius is : “<<ctemp;
cout<<endl;
return 0;
}