Objects and Classes in Java

     A class is a blueprint or a template for creating objects. It defines the properties and behaviors that objects of the class will have. An object, on the other hand, is an instance of a class. Objects are created based on the structure defined by the class.

// Defining a class

public class Car {

// Properties or fields

String brand;

String model;

int year;

// Constructor (a special method to initialize objects)

public Car(String brand, String model, int year) {

this.brand = brand;

this.model = model;

this.year = year;

}

// Method (a function associated with the class)

public void displayInfo() {

System.out.println("Brand: " + brand);

System.out.println("Model: " + model);

System.out.println("Year: " + year);

}

}

// Creating objects of the Car class

public class Main {

public static void main(String[] args) {

// Creating two Car objects

Car car1 = new Car("Toyota", "Camry", 2022);

Car car2 = new Car("Honda", "Civic", 2021);

// Calling methods on objects

car1.displayInfo();

System.out.println(); // Adding a line break

car2.displayInfo();

}

}

In this example, we have a class named Car with three properties (brand, model, and year), a constructor to initialize the object, and a method (displayInfo) to display information about the car. In the Main class, we create two instances of the Car class (car1 and car2) and then call the displayInfo method on each of them.

Key concepts related to classes and objects in Java:

1. Class: A blueprint or template that defines the structure and behavior of objects.
2. Object: An instance of a class. It is a real-world entity that can be uniquely identified.
3. Constructor: A special method used for initializing objects. It has the same name as the class and is called when an object is created.
4. Method: Functions defined within a class that represent the behavior of objects.
5. Field or Property: Variables that represent the attributes or characteristics of objects.