---

What is Encapsulation?

Encapsulation is the process of wrapping data (variables) and code (methods) together as a single unit — typically inside a class.
It’s also called "data hiding" because it restricts direct access to class variables.

Key Features of Encapsulation

• Make variables private
• Provide public getter and setter methods to access/change them
• Control what data can be seen or modified

Example of Encapsulation:

    
    class BankAccount {
        private double balance;  // private variable (hidden)

        // Getter
        public double getBalance() {
            return balance;
        }

        // Setter
        public void setBalance(double amount) {
            if (amount >= 0) {
                balance = amount;
            } else {
                System.out.println("Invalid amount!");
            }
        }
    }

    public class Main {
        public static void main(String[] args) {
            BankAccount acc = new BankAccount();
            acc.setBalance(5000.75);       // modify using setter
            System.out.println(acc.getBalance());  // access using getter
        }
    }
    
    

Output:

    
    5000.75
    
    

Why Use Encapsulation?

Benefit	Description
Data Hiding	Prevents direct access to sensitive fields
Controlled Access	Only expose what is needed
Security	Protects object’s internal state
Code Flexibility	Easy to update or refactor
Cleaner API	Users interact via methods, not internal variables

Real Life Analogy

Imagine a coffee machine:
• You press a button to make coffee.
• You can’t see or access internal parts like wiring or boiler.
• That’s encapsulation — the complexity is hidden, and only the interface is exposed.

Summary

Concept	Description
What	Wrapping data and methods inside a class
How	Use private + getters & setters
Benefit	Security, clean code, control, and maintainability

---