Four Pillars Java

Java, as an object-oriented programming language, is built upon four fundamental principles known as the Four Pillars of OOP (Object-Oriented Programming). These pillars define how Java structures and manipulates data efficiently. The four pillars are:

1. Encapsulation
2. Abstraction
3. Inheritance
4. Polymorphism

Each of these plays a crucial role in designing modular, scalable, and maintainable applications. Let’s explore them in detail with code examples.

1. Encapsulation

Encapsulation is the mechanism of restricting direct access to some components of an object and only exposing what is necessary. This is achieved using access modifiers like private, protected, and public.

Importance of Encapsulation:

• Hides implementation details from the outside world
• Improves security by preventing unintended modifications
• Enhances maintainability and reusability

Example:

class BankAccount {
    private double balance; // Encapsulated data


public BankAccount(double balance) {
        this.balance = balance;
    }
    public double getBalance() { // Getter method
        return balance;
    }
    public void deposit(double amount) { // Method with controlled access
        if (amount > 0) {
            balance += amount;
        }
    }
}
public class…