Case Statement

Case statements are a sign that a method contains too much knowledge.

Symptoms

• Case statements that check the class of an object.
• Case statements that check a type code.
• Divergent Change caused by changing or adding when clauses.
• Shotgun Surgery⭐ caused by duplicating the case statement.

Solutions

• Replace Type Code with Subclasses if the case statement is checking a type code, such as question_type.
• Replace Conditional with Polymorphism when the case statement is checking the class of an object.
• Use Convention Over Configuration when selecting strategy based on a string name.