Code Smell 26 — Exceptions Polluting

It is very nice to have lots of different exceptions. Your code is declarative and robust. Or not?

Photo by Nick van den Berg on Unsplash

Problems

• Over Design
• Namespace Pollution

Solutions

1. Avoid creating anemic exceptions as globals.
2. Create exceptions only if they behave differently.
3. Model exceptions with objects. Classes are handy for lazy programmers.

Sample Code

Wrong

Right

Detection

New exceptions should override behavior methods.

No. code, description, resumable, etc are not behavioral.

Tags

• Abuser
• Naming

Conclusion

You would not create different classes for every Person instance, so they return different names. Why would you do it with exceptions.

How often do you catch a specific exception?.

Go out and check your code.

Is it necessary to be a class?

You are already coupled to the class. Couple to the description instead.

Exception instances should NOT be Singletons.

Relations

Code Smell 01 — Anemic Models

You will fall to ruin because you believe that exceptions to the rule make new rules.

Pierce Brown

Software Engineering Great Quotes

This article is part of the CodeSmell Series.

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