Why SOLID principles guide maintainable design in LLD - Quick Recap

Recall & Review

beginner

What does the 'S' in SOLID stand for?

The 'S' stands for Single Responsibility Principle, which means a class should have only one reason to change, focusing on a single task.

beginner

Explain the Open/Closed Principle in simple terms.

It means software entities like classes should be open for extension but closed for modification, so you can add new features without changing existing code.

intermediate

Why is the Liskov Substitution Principle important for maintainability?

Because it ensures that subclasses can replace their parent classes without breaking the program, making code easier to extend and maintain.

intermediate

What does the Interface Segregation Principle encourage?

It encourages creating small, specific interfaces rather than large, general ones, so classes only implement what they actually need.

intermediate

Describe the Dependency Inversion Principle in simple words.

It means high-level modules should not depend on low-level modules directly; both should depend on abstractions, which helps reduce tight coupling.

Which SOLID principle helps avoid changing existing code when adding new features?

A Open/Closed Principle

B Single Responsibility Principle

C Liskov Substitution Principle

D Dependency Inversion Principle

The Open/Closed Principle states that software should be open for extension but closed for modification.

What does the Single Responsibility Principle ensure?

A A class has only one reason to change

B A class has multiple reasons to change

C Classes depend on concrete implementations

D Interfaces are large and general

Single Responsibility Principle means a class should have only one reason to change.

Which principle promotes using small, specific interfaces?

A Open/Closed Principle

B Dependency Inversion Principle

C Liskov Substitution Principle

D Interface Segregation Principle

Interface Segregation Principle encourages small, client-specific interfaces.

Liskov Substitution Principle means:

A Interfaces should be large and general

B Subclasses can replace parent classes without errors

C High-level modules depend on low-level modules

D Classes should have one responsibility

Liskov Substitution Principle ensures subclasses can replace their base classes safely.

Dependency Inversion Principle helps by:

A Combining multiple responsibilities in one class

B Making classes depend on concrete implementations

C Making high-level modules depend on abstractions

D Creating large interfaces

Dependency Inversion Principle states that both high-level and low-level modules should depend on abstractions.

Explain how SOLID principles help make software easier to maintain.

Think about how each principle reduces problems when changing or extending code.

Describe a real-life example that illustrates the Single Responsibility Principle.

Imagine a team where each member has a clear, single task.