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All the animals in the animal class have similar behaviours such as eating, drinking, and sleeping.
                  They also have similar properties, such as colour, size, and number of legs.

                  In the same way, a class in Java contains different types of objects that have similar properties
                  and behaviour. After declaring a class, we can create any number of objects from it.

                      BASIC PRINCIPLES OF OOP

                  There are four principles of Object-Oriented Programming (OOP) which are as follows:
                      Encapsulation             Data Abstraction             Inheritance          Polymorphism

                  Let us learn about these in detail.

                  Encapsulation
                  Encapsulation refers to the bundling of data members and member methods into a single unit,
                  or class. This principle ensures that data can only be accessed through associated methods, thus
                  protecting it from outside interference and misuse. This concept is also known as data hiding.

                  A real-life example is a capsule. In general, a capsule is a small case or container, that protects
                  the medication inside from contamination by outside elements.
                  Data Abstraction

                  Data Abstraction is the principle of representing only the essential features of an object while
                  hiding non-essential details from the user.
                  For instance, when traveling in  a car as a  passenger,  you are concerned only with reaching
                  your  destination,  not with  how  the  driver  operates  the  car  by  pressing  the  clutch,  brake,  and
                  accelerator.

                  Inheritance

                  The procedure of generating a new class with the help of an already created class, by using
                  its properties and functionality is said to be inheritance. It is one of the important pillars of
                  Object-Oriented Programming. For example, in real world, a child inherits the properties
                  (both materialistic and non-materialistic) of its parents, who, in turn inherited them from
                  their parents.


                  Polymorphism
                  The word  Polymorphism comes from the Greek word  meaning “many forms” ("poly" means
                  many and "morphe" means form). It is the ability of a variable, function, or object to take on
                  multiple forms. For example, the term "car" can refer to a family car, a taxi used by the general
                  public, or a pool car used by people.

                      INTRODUCING BLUEJ

                  Previously, simple text editors such as Notepad were used to develop
                  Java programs. With advancements in technology, various Integrated
                  Development Environments (IDE) are now available, often free of cost.
                  One such IDE is BlueJ.




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