Code Smell 01 — Anemic Models

Your objects are a bunch of public attributes without behavior.

Photo by Stacey Vandergriff on Unsplash

Protocol is empty (with setters/getters).

If we ask a domain expert to describe an entity he/she would hardly tell it is ‘a bunch of attributes’.

Problems

• No Encapsulation.
• No mapping to real world entities.
• Duplicate Code
• Coupling

Solutions

1) Find Responsibilities.

2) Protect your attributes.

3) Hide implementations.

4) Delegate

Examples

• DTOs

Sample Code

Wrong

Right

Detection

Detection can be automated with sophisticated linters ignoring setters and getters and counting real behavior methods.

Also Known as

• Data Class

Tags

• Anemic
• OOP as Data
• Encapsulation
• Setters/Getters
• Mutability

More info

• Wikipedia
• Refactoring Guru
• Nude Models — Part I : Setters
• Nude Models — Part II : Getters
• How to Decouple a Legacy System

This article is part of the CodeSmell Series.

How to Find the Stinky parts of your Code