feat: Add Encapsulation class to demonstrate private fields with getters and setters

WHAT the code does:
Defines an Encapsulation class with private attributes:
- color, brand, model, countryOrigin, year, speed.
Implements behavior methods:
- accelerate(int increment): increases speed.
- brake(int decrement): decreases speed but prevents it from going below zero.
Provides getter and setter methods for all attributes to control access.
main() demonstrates usage by:
- Setting attributes via setters.
- Updating speed with accelerate and brake.
- Printing details via getters.

WHY this matters:
Illustrates encapsulation, a core principle of object-oriented programming:
- Fields are hidden (private) and accessed through controlled interfaces (getters/setters).
- Prevents direct modification of internal state, enforcing better data integrity.
Shows how encapsulation separates representation (fields) from interaction (methods).

HOW it works:
In main():
- A car object is created and initialized with setters (brand = Tesla, model = Model S, etc.).
- accelerate(50) sets speed to 50.
- brake(20) reduces speed to 30.
- Getter methods retrieve field values for display.

Tips and gotchas:
Encapsulation is stronger when setters include validation (e.g., rejecting negative year or unrealistic speeds).
Overusing setters/getters without logic reduces them to boilerplate; consider immutability or records for simpler cases.
The toString() method could be overridden to simplify object state printing instead of multiple getter calls.
For real-world systems, builders or constructors may be preferable for setting required fields.

Use-cases:
Educational demonstration of encapsulation in Java.
Useful for modeling entities where state must be controlled and validated.
Foundation for larger systems applying OOP principles like abstraction and inheritance.

Short key: class-encapsulation private-fields getters-setters oop.

Signed-off-by: https://github.com/Someshdiwan <[email protected]>

Author: Someshdiwan

Section11ObjectOrientedProgramming/OOPs 2.O/src/Encapsulation.java

@@ -1,75 +1,95 @@
-//Bundling of data and methods into a single unit.
-//Class ke Andar Band Kardeya hai  Data and methods ko.
-//Single Unit Mai Sab Band keya hai.
-//Bundle kar ke data hide kar raha hai Private use karke.
+/*Bundling of data and methods into a single unit.
+Class ke Andar Band Kardeya hai Data and methods ko.
+Single Unit Mai Sab Band keya hai.
+Bundle kar ke data hide kar raha hai Private use karke.*/
 
-public class Encapsulation
-{
-        private String Color;
-        private String brand;
-        private String Model;
-        private String CountryOrigin;
-        //Sab Private to set kaise kare Getters and setters method se
-        private int year;
-        private int speed;
+public class Encapsulation {
+    // Private attributes
+    private String color;
+    private String brand;
+    private String model;
+    private String countryOrigin;
+    private int year;
+    private int speed;
 
-        //Method hai. Speed ko increment kar raha hai.
-        public void accelerate(int increment)
-        {
-            speed += increment;
+    // Behavior methods
+    public void accelerate(int increment) {
+        speed += increment;
+    }
+
+    public void brake(int decrement) {
+        speed -= decrement;
+        if (speed < 0) {
+            speed = 0;
         }
+    }
 
+    // Getters and setters
     public String getColor() {
-        return Color;
+        return color;
     }
-
     public void setColor(String color) {
-        Color = color;
+        this.color = color;
     }
 
     public String getBrand() {
         return brand;
     }
-
     public void setBrand(String brand) {
         this.brand = brand;
     }
 
     public String getModel() {
-        return Model;
+        return model;
+    }
+    public void setModel(String model) {
+        this.model = model;
     }
 
     public String getCountryOrigin() {
-        return CountryOrigin;
+        return countryOrigin;
     }
-
     public void setCountryOrigin(String countryOrigin) {
-        CountryOrigin = countryOrigin;
+        this.countryOrigin = countryOrigin;
     }
 
     public int getYear() {
         return year;
     }
+    public void setYear(int year) {
+        this.year = year;
+    }
 
     public int getSpeed() {
         return speed;
     }
-
     public void setSpeed(int speed) {
         this.speed = speed;
     }
 
-    //Behavior hai toh method mai likh te hai
-        public void brak(int decrement)
-        {
-            speed -= decrement;
-            if(speed<0)
-            {
-                speed=0;
-            }
-        }
-        public static void main(String[] args) {
-            ClassBluePrint car = new ClassBluePrint();
+    // Main method to test encapsulation
+    public static void main(String[] args) {
+        Encapsulation car = new Encapsulation();
 
-        }
-}
+        // Set values using setters.
+        car.setBrand("Tesla");
+        car.setModel("Model S");
+        car.setColor("Red");
+        car.setCountryOrigin("USA");
+        car.setYear(2023);
+        car.setSpeed(0);
+
+        // Use behavior methods
+        car.accelerate(50);
+        car.brake(20);
+
+        // Access values using getters.
+        System.out.println("Car Details:");
+        System.out.println("Brand: " + car.getBrand());
+        System.out.println("Model: " + car.getModel());
+        System.out.println("Color: " + car.getColor());
+        System.out.println("Country of Origin: " + car.getCountryOrigin());
+        System.out.println("Year: " + car.getYear());
+        System.out.println("Speed: " + car.getSpeed() + " km/h");
+    }
+}