Encapsulation in Dart

What is Encapsulation?

Imagine you are a toy maker crafting special dolls in your workshop. Each doll has a hidden surprise inside, like a small pocket with a tiny gift. Now, encapsulation is like wrapping these surprises securely inside the doll.

In computer programming, encapsulation means bundling together the important stuff (data and functions) related to a specific thing, just like hiding the surprise inside the doll. It helps keep things organized and prevents anyone from accidentally messing with the surprises or the workings of the doll.

Why is it Important?

Encapsulation is important because it ensures that the surprises inside the doll are protected. It keeps everything neatly packaged, making it easier to manage and preventing any unintentional changes to the doll’s hidden treasures.

Imagine: Think of encapsulation as wrapping up the surprises inside a special doll, and the doll represents something in your computer program. The surprises (data and functions) are kept safe and sound, hidden away from anyone who doesn’t need to interact with them.

Another way to think it is picturing a magical box that only opens with a secret code. The box (class) contains special items (data) and can perform amazing tricks (methods). You don’t need to know how the tricks work; you just need to know the secret code to access them!

Let’s try to Visualize the below code:

/**
 * Encapsulation Example
 * 
 * Imagine you are a toy maker crafting special dolls in your workshop.
 * Each doll has a hidden surprise inside, like a small pocket with a tiny gift.
 * In computer programming, encapsulation means bundling together the important stuff (data and functions)
 * related to a specific thing, just like hiding the surprise inside the doll.
 * It helps keep things organized and prevents anyone from accidentally messing with the surprises or the workings of the doll.
 */

// Define a class representing a Doll with encapsulated surprises
class Doll {
  // Private variables (encapsulated data)
  String _hiddenGift;

  // Constructor to initialize the Doll with a hidden gift
  Doll(String hiddenGift) {
    this._hiddenGift = hiddenGift;
  }

  /**
   * Method to reveal the hidden gift
   * This method encapsulates the process of revealing the surprise inside the doll.
   * It ensures that the hidden gift is only accessed through this controlled method.
   */
  String revealHiddenGift() {
    return _hiddenGift;
  }
}

/**
 * Main function where the program execution starts
 * Imagine this as the toy maker's workshop where dolls are created and their surprises are revealed.
 */
void main() {
  // Create a Doll with a hidden gift
  Doll specialDoll = Doll('A tiny magical key');

  // Attempting to access the hidden gift directly will result in an error due to encapsulation
  // Uncomment the line below to see the encapsulation in action:
  // print(specialDoll._hiddenGift);

  // Reveal the hidden gift using the encapsulated method
  String revealedGift = specialDoll.revealHiddenGift();

  // Display the revealed gift
  print('Revealed Gift: $revealedGift');
}