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1.3 PRINCIPLES OF OBJECT-ORIENTED PROGRAMMING
                  As you know Encapsulation, Data Abstraction, Inheritance and Polymorphism are the four pillars of Object-Oriented
                  Programming. Let us learn about them in detail.




                                                            Principles of
                                                Object-Oriented Programming






















                  1.3.1 Encapsulation
                  Encapsulation is one of the basic concepts of object-oriented programming (OOP).
                  The wrapping up of data members and member functions together into a single   Methods    Variables
                  unit is called encapsulation. It means that data can be accessed in the associated
                  function only and safe from outside interference and misuse thus leading to the      CLASS
                  important concept of OOP known as data hiding.                                Concept of Encapsulation

                  A real-life example is a capsule. In general, a capsule is a small case or container, especially round or cylindrical in
                  shape which protects the drug inside it from getting contaminated with the dust particles from outside.

                  Similarly, Methods and Variables are enclosed within a unit called class.
                  Example of Encapsulation using class:

                  Both Data Members and Member Methods are defined within the body of the class country.


                                   class country                                     Class name
                                       {
                                           String name;
                                           String capital;                           Data Members
                                           void input ()
                                           {
                                               name= "India" ;                       Member Methods
                                               capital= "New Delhi";
                                           }
                                           void display ()
                                           {
                                               System.out.println ("Name of the Country "+name);
                                               System.out.println ("Name of Capital" +capital);
                                           }
                                       }


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