a - What is encapsulation Encapsulation is one of the fundamental concepts in object-oriented programming (OOP) It is used to restrict access to some of an object's internal state This helps in protecting data integrity, managing complexity, and promoting maintainability... by allowing controlled access to internal properties and behaviors. Core Concepts of Encapsulation: 1. Data Hiding: Hide the internal state (variables) of an object to prevent unintended modifications. 2. Access Control: Provide controlled access (via methods) to the internal state. 3. Abstraction: Expose only the necessary parts of the object’s behavior (methods), hiding implementation details. Why Encapsulation Matters? 1. Security: Prevents unauthorized changes to internal state. 2. Maintainability: Makes code easier to modify and debug. 3. Reusability: Encapsulated code is more modular and reusable. 4. Scalability: Reduces dependencies and makes large systems manageable.
b - How to Achieve Encapsulation Part 1 1. Using Closures (Function Scopes) Closures allow you to create private variables and functions that are not accessible outside the scope of the function. Advantages: Strong data privacy. Prevents direct tampering with internal state. 2. Using ES6 Classes with Private Fields (#) ES6 introduced private class fields, denoted by #, which cannot be accessed from outside the class. Advantages: Native support for private fields. Clean and readable code with modern syntax. 3. Using ES6 Classes with Getter/Setter Use get and set methods to control access to internal state. Advantages: Enforces validation and constraints. Encapsulates logic for reading and writing data.
c - How to Achieve Encapsulation Part 2 4. Using ES6 Modules (Private Module Scope) Modules allow you to expose only certain parts of your code and keep the rest private. Advantages: Clean separation of public and private code. Encourages modular and reusable code. 5. Using IIFE (Immediately Invoked Function Expression) IIFEs allow you to create a private scope and expose only the necessary methods. Advantages: Works in older JavaScript environments. Encapsulates state and logic in a single scope. When to Use Which Approach: Closures Best For → Small, standalone utility functions or modules Notes → Not suitable for large-scale OOP ES6 Classes Best For → Modern, scalable applications with private fields Notes → Supports class-based OOP Getters/Setters Best For → Fine-grained control over data access and validation Notes → Enhances readability and safety ES6 Modules Best For → Modular applications with strict separation of concerns Notes → Ideal for large projects IIFE Best For → Legacy environments or libraries where ES6 isn't supported Notes → Less readable than ES6 classes