Creating Object

Syntax to create an Object

     ClassName objectName = new ClassName();

     Example

          Person personA = new Person();

          Here Person is the class name

          personA is the object created for the class Person.

    Once the class is defiined, you can create any number of objects to it.

               Person personB = new Person();

               Person personC = new Person();

How to access properties of an object

     java provides '.' opertor to access th properties of an object.

     Syntax:

          objectName.propertyName = value;

     Example

          personA.height = 6;

          personB.height = 5.5;

How to call the behaviors

     Just like how you are accessing properties, you can call the behaviours.

     Syntax

     objectName.behavior();

     Example

     personA.getHeight();

     personB.getHeight();

Complete Working Example of Person class

class Person{
 float height, weight;
 String color, country;
 
 float getHeight(){
  return height;
 }
 
 float getWeight(){
  return weight;
 }
 
 String getColor(){
  return color;
 }
 
 String getCountry(){
  return country;
 }
 
 public static void main(String args[]){
 
  /* Declaring two person objects */
  Person personA = new Person();
  Person personB = new Person();
  
  /* Setting properties for personA object */
  personA.height = 6;
  personA.weight = 75;
  personA.color = "White";
  personA.country = "India";
  
  /* Setting properties for personB object */
  personB.height = 5.5f;
  personB.weight = 76;
  personB.color = "Black";
  personB.country = "America";
  
  /* Calling the behaviors and printing the details of personA */
  System.out.println("PersonA Height is " + personA.getHeight());
  System.out.println("PersonA Weight is " + personA.getWeight());
  System.out.println("PersonA color is " + personA.getColor());
  System.out.println("PersonA country is " + personA.getCountry());
  System.out.println();
  
  /* Calling the behaviors and printing the details of personB */
  System.out.println("PersonB Height is " + personB.getHeight());
  System.out.println("PersonB Weight is " + personB.getWeight());
  System.out.println("PersonB color is " + personB.getColor());
  System.out.println("PersonB country is " + personB.getCountry());
 }
}

   
Output

PersonA Height is 6.0
PersonA Weight is 75.0
PersonA color is White
PersonA country is India

PersonB Height is 5.5
PersonB Weight is 76.0
PersonB color is Black
PersonB country is America

  

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