Classes and Objects in Java

In Java, A Class is a blueprint or template for creating objects. It defines the properties (attributes) and behaviors (methods) that objects of that class will have.
On the other hand, An object is an instance of a class, created using the new keyword followed by the class name. Each object has its own set of attributes and can perform actions defined by its class’s methods. Classes and objects form the basis of object-oriented programming (OOP) in Java, allowing for code organization, reusability, and abstraction.

In the below PDF we discuss about Classes & Objects in Java in detail in simple language, Hope this will help in better understanding.

Creating a Class in Java:

Let’s start by creating a simple class in Java:

public class Car {
// Attributes
String make;
String model;
int year;
// Constructor
public Car(String make, String model, int year) {
this.make = make;
this.model = model;
this.year = year;
}
// Method
public void displayInfo() {
System.out.println("Make: " + make);
System.out.println("Model: " + model);
System.out.println("Year: " + year);
}
}

In this example, we’ve defined a class named Car with attributes make, model, and year, along with a constructor to initialize these attributes and a method displayInfo() to print the information about the car.

Creating Objects:

Now, let’s create objects of the Car class:

public class Main {
public static void main(String[] args) {
// Create objects
Car car1 = new Car("Toyota", "Camry", 2020);
Car car2 = new Car("Honda", "Civic", 2018);

// Call methods
car1.displayInfo();
car2.displayInfo();
}
}

In this Main class, we create two Car objects, car1 and car2, by using the new keyword followed by the class constructor. We then call the displayInfo() method on each object to print their information.

Conclusion

Classes and objects are fundamental concepts in Java programming, providing a powerful mechanism for organizing and modeling real-world entities. By understanding how to define classes, create objects, and leverage object-oriented principles such as encapsulation, inheritance, and polymorphism, developers can write clean, modular, and maintainable code. As you continue your journey in Java development, mastering these concepts will be essential for building robust and scalable applications.