1. Object Oriented Analysis and Design
Object-Oriented Concepts

2. OOAD Concepts Class Object Encapsulation Abstraction Inheritance
Polymorphism
Message passing
Dynamic binding

3. Classes & Objects Data / attributes / field/state Method / Behaviour
Describe the characteristics
Method / Behaviour
Perform operations
Perform object to object communication

4. Classes & Objects Class Object
Category or group of things that have the same attributes and the same behaviors.
Class is a decryption of properties and behaviors which a collection of same type objects can have
Object
Instance of a class
Object is a bundle of properties and behaviors
An object stores its state in fields (variables) and exposes its behavior through methods (functions)

5. Classes & Objects Attribute/Field/variable Data/Value Student Nimal
age 21
Study()
Study()
Class
Object

6. Classes & Objects Class Object User defined data type
Instance of user defined data type
Prototype or model
Containing features
Do not occupy memory
Occupy memory
Cant manipulate since its not in memory
Can manipulate

7. Classes & Objects class Student { private : int AM; int EM; public :
void ReadMarks()
cout<<"Enter Assignment Marks : ";
cin>>AM; }
void printGrade()
cout<<"Grade :"<<(AM+AM)/2; };
main() {
Student Nimal;
Nimal.ReadMarks();
Nimal.printGrade();
getch(); }

8. Classes & Objects Member functions defined outside class
Binary scope resolution operator (::) ties member name to class name
scope resolution operator help uniquely identifying functions of a particular class
Different classes can have member functions with same name

9. Classes & Objects
class Student { private : int AM; int EM; public : void ReadMarks(); void printGrade(); }; void Student::ReadMarks() cout<<"Enter Assignment Marks : "; cin>>AM; cin>>AM; }
void Student::printGrade() {
cout<<"Grade :"<<(AM+AM)/2; }
main()
Student Nimal;
Nimal.ReadMarks();
Nimal.printGrade();
getch();

10. Constructors
Constructors are special member functions of any class, which are invoked at the moment an instances of the class are created. They are special functions that have the same name as their class.
Have the same name as the class.
It may take arguments.
It cannot return a value [including void].

11. Constructors Default Constructor Parameterized Constructor
Accepts no parameters
Called if no user-defined constructors
Parameterized Constructor
A constructor that receives arguments/parameters
Class:: Circle() {}
Circle::Circle(int r)
{ radius = r;}

12. Destructors Special member function Having same name as class
Preceded with tilde (~)
No arguments
No return value
Cannot be overloaded
Invoked before system reclaims object’s memory
Used in reusing memory for new objects

13. Pointers
Memory location which hold the address of another memory location/ variable
int x=5;
int *p;
p= &x;
*p=10;