Pattern Design Anti-Patterns and Refactoring 2

Question 1

The 'Feature Envy' code smell describes a method that:

Accepted Answer

Seems more interested in the data of another class than its own

Answer

Feature Envy occurs when a method accesses the data or methods of another class more than its own, suggesting it belongs in that other class.

Question 2

Replace Conditional with Polymorphism refactoring eliminates:

Accepted Answer

Long if-else or switch statements based on object type

Answer

Instead of a switch on object type to select behavior, each subclass overrides a method with its own behavior, leveraging polymorphism.

Question 3

The 'Primitive Obsession' code smell is addressed by:

Accepted Answer

Replacing primitive data types with small value objects or domain classes

Answer

Using primitives (String, int) for domain concepts (PhoneNumber, Money) loses meaning and validation — wrapping them in value objects adds clarity and safety.

Question 4

The 'Dead Code' anti-pattern refers to:

Accepted Answer

Code that is never executed because it is unreachable

Answer

Dead code is unreachable or never-called code that clutters the codebase and should be removed to reduce maintenance overhead.

Question 5

The 'Blob' anti-pattern is identified by a class that has:

Accepted Answer

Hundreds of attributes and methods performing unrelated functions

Answer

A Blob (or God Class) is a class that has absorbed so much responsibility it becomes a monolith within the design, making decomposition urgent.

Pattern Design Practice Test

Pattern Design Practice Test

Pattern Design Anti-Patterns and Refactoring 2