Encapsulating Complexity

Overview

Hide HOW things work. Expose only WHAT they do. Work at domain level (Users, Orders, Config), not implementation level (dicts, SQL rows, JSON files).

Core principle: The point of encapsulation is to create possibilities (many ways to implement) and restrict possibilities (one way to use). Implementation details hidden = free to change implementation without breaking clients.

Violating the letter of this rule is violating the spirit of information hiding.

When to Use

Apply to every class and interface:

• Designing new classes/modules
• Creating public APIs
• Reviewing code for abstraction leaks
• Refactoring to improve maintainability