Basics
Features of Object Oriented Programing Language.
Features of OOP : -
1.Class
2.Object
3.Inheritance
4.Polymorphism
5.Data Hiding And
Encapsuation
Class : - Class is a
group of object of same of same type .Once a class has declared we
can create multiple numbers of their objects. E.g potato, onion,
Cabbage are the object of class vegetables.
Example
of Class in JAVA: -
Class Hello //Class hello
{
}
Object : - Objects are
collection of entities .Object takes space in memory . Objects are
instances of class. When program is executed the object the object
interacts by sending message to another . Each object contain data
and code to mainpulate the data.
Example
of Class and Objects : -
Class Hello //Class hello
{
void run () //Member Function
{
System.out.print(“Hello
World”);
}
}
class demo
{
public static void main
(String args[])
{
Hello h=new Hello(); //
Creating Object of class hello
h.run(); //Calling
Method of class hello
}
}
Inheritance : -
Inheritance is an Approach through in which object of one class can
acquired the property of parents class. Inheritance is used for
resuablity of codes.
Example
of Inheritance
Class employee
{
int salary=1000;
}
//Extend is used to access
the feature and property of parent class
Class developer extends
employee
{
int bonus=500;
public static void
main(String args[])
{
developer d=new developer();
System.out.println(“Salary
is : ”+d.salary);
System.out.println(“Bonus
is : ”+d.bonus);
}
}
Polymorphism : - the
word polymorphism means many form any operation may exhibite
different behaviour in different instance . The behaviour depend on
what type of operation we used.
Example :- Function
Overloading,Operator Overloading.
Example
of Polymorphism
class adding
{
int add(int a,int b) //method
one
{
return a+b;
}
// method two same name but
differen parameter
int add(int a,int b,int c)
{
return a+b+c;
}
}
class demo
{
public static void
main(String args[])
{
adding abc=new adding();
System.out.println(“Sum of
10 , 20 , 30 is : ”+abc.add(10,20,30));
System.out.println(“Sum of
10 , 20 is : ”+abc.add(10,20));
}
}
Data hiding and
Encapsulation : - Since wrapping up of data member and menber in
a single class is known as encapsulation. Through in which data as
are not access by the outside world only member function can access
the data this is data hiding. And Also when we hide the complexity
of program are known as abstraction . And only essential feature can
access. Like when we sending sms we dont what its internal processing
we only give inputs.
Example
of Encapsulation
class hello
{
int a;
void geta()
{
return a;
}
void seta(String n)
{
this.a=n;
}
}
//hiding the above class and
then we only calling the method dont know about the internal
processing.
class calling
{
public static void
main(String args[])
{
hello h=new hello();
h.seta(“Charles”);
System.out.print(“Name is
”+h.geta());
}
}
