[Java] Java OOPs Concepts

 Java OOPs Concepts

1. OOPs(Object Oriented Programming System)

- Object means a real world entity such as pen, chair, table, etc..

- OOPs is a methodology or paradigm to design a program using classes and objects

- Object, Class, Inheritance, Polymorphism, Abstaraction, Encapsulation

1_1. Object 

- Any entity that has state and behavior is known as an object

1_2. Class

- Collection of objects 

1_3. Inheritance

- When on object acquires all the properties and behaviours of parent object

- It provides code reusability. It is used to achieve runtime polymorphism

1_4. Polymorphism

- When one task is performed by different ways i.e. known as polymorphism

- In java, we use method overloading and method overriding to achieve polymorphism

1_5. Abstraction

- Hiding internal details and showing functionality

- In java, we use abstraction class and interface to achieve abstraciton

1_6. Encapsulation

- Binding (or wrapping) code and data together into a single unit 

- A java class is the example of encapsulation, Java bean is the fully encapsulated class

because all the data members are private here

2. What is difference between object-oriented programming language and object-based programming language(Javascript)?

- Object based programming language follows all the features of OOPs except Inheritance.