Object in JAVA

February 11, 2023

Java object

A house, motorcycle, truck, notebook, sofa, or computer are examples of objects. An object is any item with state and activity. It could be mental or physical (tangible and intangible). An example of an intangible entity is the financial system.

More on Java Objects :

Everything in Java is built upon the objects and classes, as well as their traits and methods. A truck, for example, is an entity in the actual world. Along with features like accelerate and break, the truck also has qualities like mass and colors.
Any kind of class can have an object as an instance.
Classes are logical constructs, whereas objects are the physical manifestations of a class, and these are the things that are actually taking up memory space.

Objects are categorized into three types:

State: It simply means the value of the objects from its data type . In the real world every object holds a different set of values in some sort of manner. In other words .The states of a Java object are kept in fields that correspond to the various aspects of the object. For reference, a handgun with a seven clip in a third-person assault video game has eleven total states: one state for each bullet (e.g., nine, five, six, etc.), plus another state when the clip is empty.

Identity : It is like whether one object is different from another or not. And to find the where the object is store in the memory or in other words we can say that The identity is just a feature used to identify that thing; examples include a random Id card or a memory address. Even while basic objects like a torch only have two values (power on and power off) and actions (power on, power off), they nonetheless have identities, such as the manufacture ID of that particular product.

Behavior : It is most likely how our object behave on different set of input and aslo In order to enrich UIComponents with functionality not specifically described by the element implementation itself, behaviours are objects that are connected to UIComponents.

How to create a class :

To create a object of any class , we use the new keyword . This new keyword create the object at runtime.

Example :

Classname objectName = newKeyword classname();

Run

class Boxers {
//.....variables...
//.....methods.....
}
public class Main
public static void main(String [] args){
//creating new object of class type Boxers
Boxers var = new Boxers();
}
}

Ways to Initialize an Object

Parent to parent reference.
Parent to child reference.
Child to child reference.

Code Example :

Run

class Boxers {
//.....variables...
//.....methods.....
}
class RedBoxer extends Boxers{
//This class contains all the features of class Boxers.
}
public class Main{
public static void main(String [] args){
//parent to parent
Boxers var = new Boxers();
//parent to child
Boxers var1 = new RedBoxer();
//child to child 
RedBoxer var2 = new RedBoxer();
}
}

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