- In OOP, each object is independent unit with a unique identity , just as object in a real world.
- Objects also have characteristics , which are used to describe them.
- Example – a car can be red or blue ,a mug can be full or empty .These characteristics are called attributes.
- An attributes describes the current state of an object.
- In OOP , each object have three dimensions identity , attributes & behaviour.
Classes:-
- A class describes what the object will be , but is Separate from the Object itself.
- In other words, classes can be described as blueprints, descriptions or definitions for an object.
- We can use Same class as an blue prints for creating multiple objects.
- The first step is to define the class , which then becomes a blue print for object creation.
- Each class have a name & each is used to define attributes & behaviour
- Example -Consider a class Person which has Attributes :name , height , weight , gender , age Behaviour: walk , run , jump , speak , sleep .
Methods:-
- Method defines behaviour. A method is a collection of statements that are grouped together to perform an operation.
- System.out.println() is an example of a method.
- We can define our own method .
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class Myclass{ //creating a method static void sayhello(){ System.out.println("Hello World"); } public static void main(String args[]){ sayhello(); //static method can be called directly without creating object } }