Introducing Java Object Oriented Programming Concepts

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OOPC-Object Oriented Programming Concepts
Java Class Heirachy

1. Object
2. Class
3. Method
4. Variable

Standards

Coding Standards for Classes Usually class name should be noun starting with uppercase letter.




1st Letter Uppercase - Car
1st Letter Lowercase - car
Parameter List -           car()


Operators

Operators are used to perform operations on variables and values.




.           Dot Operator
=          Assignmental Operator  -  Here the substitution is done.
==       Equalization Operator  -  Here the comparison is made.

                                     
Class & Object

Object

An object is an identifiable object with some properties and behavior. Because an object is simply a real-world object, it is easier to understand the concept of objects when we consider real-life examples around us.

You will be surrounded by a number of objects with certain characteristics and behaviors.

Example:- we can say that 'man' is an object. Its properties are: head, arms, legs etc. Its behavior: running, diving, jumping, writing etc.


Class

A class is a group of objects that share common properties and behavior.

Example:- we can consider a car as a class that has characteristics like steering wheels, seats, brakes, etc. And its behavior is mobility. But we can say Honda City having a reg.number 4654 is an ‘object’ that belongs to the class ‘car’.


In relation to the Properties and Behaviors of an Object, the Object is used as a Class, Properties Variable and Behaviors Methods in Programming. Then Variables and Methods are used in the Class as the Properties and Behaviors of the Object are.

That is, a class is a template created in relation to a certain object. You can implement many objects by changing only the values in the class.

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