Classes and Objects in Java

In Java, a class is a blueprint for creating objects, which are instances of classes. Classes encapsulate data for the object and methods to manipulate that data.

Key Points on Classes and Objects:

• A class defines the properties (attributes) and behaviors (methods) of an object.
• An object is an instance of a class and represents a specific realization of that class.
• Classes can have constructors, which are special methods called when an object is instantiated.
• Objects can interact with each other by calling methods and accessing attributes of other objects.
• Encapsulation allows hiding the internal state of an object and exposing only the necessary parts through methods.
• Classes can inherit from other classes, promoting code reuse and establishing a hierarchical relationship.

Syntax of a Class:

public class ClassName {
    // Attributes
    // Constructors
    // Methods
}

Example of a Class in Java:

This example demonstrates a simple class called Car with attributes and methods.

public class Car {
    // Attributes
    String color;
    String model;

    // Constructor
    public Car(String color, String model) {
        this.color = color;
        this.model = model;
    }

    // Method
    public void displayInfo() {
        System.out.println("Car Model: " + model + ", Color: " + color);
    }
}

Creating Objects:

This example shows how to create objects from the Car class and call its method.

public class Main {
    public static void main(String[] args) {
        // Creating objects
        Car car1 = new Car("Red", "Toyota");
        Car car2 = new Car("Blue", "Honda");

        // Calling method
        car1.displayInfo();
        car2.displayInfo();
    }
}

Detailed Explanation:

• Class: Defines a data type by bundling data and methods that work on that data.
• Object: Represents an instance of a class, created using the new keyword.
• Constructor: A special method that initializes the object’s attributes when the object is created.
• Methods: Define the behaviors of the object, allowing interaction with its attributes.

Understanding classes and objects is fundamental to mastering Java's Object-Oriented Programming (OOP) paradigm, enabling developers to create modular and reusable code.