OOPs Concepts

OOPs Concepts

               In this page, we will learn about basics of OOPs. ObjectOriented Programming is a paradigm that provides many concepts such as inheritance, message passing, data binding etc. Simula is considered as the first objectoriented programming language. The programming paradigm where everything is represented as an object, is known as truly object-oriented programming language.Smalltalk is considered as the first truly object-oriented programming language.

OOPs (Object Oriented Programming System)Object means a real word entity such as pen, chair, table etc. Object-Oriented Programming is a methodology or paradigm to design a program using classes and objects. It simplifies the software development and maintenance by providing some concepts:

• Object
• Class
• Inheritance
• Polymorphism
• Abstraction
• Encapsulation

We will learn about these concepts one by one later.
 

Advantage of OOPs over Procedure-oriented programming language

1)OOPs makes development and maintenance easier where as in Procedure-oriented programming language it is not easy to manage if code grows as project size grows.
2)OOPs provides data hiding whereas in Procedure-oriented prgramming language a global data can be
accessed from anywhere.
3)OOPs provides ability to simulate real-world event much more effectively. We can provide the solution of
real word problem if we are using the Object-Oriented Programming language

What is difference between object oriented programming language and object based programming language?

Object based programming language follow all the features of OOPs except Inheritance. JavaScript and
VBScript are examples of object based programming languages.

Do You Know ?

• Can we overload main method ? 
• Constructor returns a value but, what ?
• Can we create a program without main method ?
• What are the 6 ways to use this keyword ?
• Why multiple inheritance is not supported in java ?
• Why use aggregation ?
• Can we override the static method ?
• What is covariant return type ?
• What are the three usage of super keyword?
• Why use instance initializer block?
• What is the usage of blank final variable ?
• What is marker or tagged interface ?
• What is runtime polymorphism or dynamic method dispatch ?
• What is the difference between static and dynamic binding ?
• How downcasting is possible in java ?
• What is the purpose of private constructor?
• What is object cloning ?

What we will learn in OOPs Concepts ?  

• Advantage of OOPs
• Naming Convention
• Object and class
• Method overloading
• Constructor
• static keyword
• this keyword with 6 usage
• Inheritance
• Aggregation
• Method Overriding
• Covariant Return Type
• super keyword
• Instance Initializer block
• final keyword
• Abstract class
• Interface
• Runtime Polymorphism
• Static and Dynamic Binding
• Downcasting with instanceof operator
• Package
• Access Modifiers
• Encapsulation
• Object Cloning