Objects and Classes in Java

Classes and Objects in Java are the fundamental concepts of Object-Oriented Programming (OOP). A class acts as a blueprint for creating objects, while an object represents a real-world entity with properties and behaviors.

Java uses classes and objects to create reusable, modular, and organized code. Almost every Java program is built using these two important concepts.

What is a Class in Java?

A class in Java is a blueprint or template used to create objects. It defines the data members (variables) and methods (functions) that describe the behavior of an object.

A class itself does not occupy memory for instance variables until an object of that class is created.

Syntax of Class in Java

class ClassName { 
    // variables
    // methods
}

Example of Class in Java

class Student {
    String name;
    void display() { 
        System.out.println(name);
    }
    }

What is an Object in Java?

An object in Java is an instance of a class. It represents a real-world entity and contains its own state and behavior.

The state of an object is represented by variables, and its behavior is represented by methods.

Creating an Object in Java

Objects in Java are created using the new keyword. The new keyword allocates memory for the object and returns its reference.

class Student {
    String name;
}
public class Main { 
    public static void main(String[] args) { 
         Student s1 = new Student(); 
         s1.name = "Alex";
        System.out.println(s1.name);
    }
 }

Class and Object Relationship in Java

Difference Between Class and Object in Java

Features of Classes and Objects in Java

Advantages of Objects and Classes in Java