Code Smell 13 - Empty Constructors
Incomplete objects cause lots of issues.
11 October, 2022
9
9
0
Contributors
No-Parameterized constructors are a code smell of an invalid object that will dangerously mutate.
Incomplete objects cause lots of issues.
TL;DR: Pass the essence to all your objects so they will not need to mutate.
Problems
•
Mutability
•
Incomplete objects
•
Concurrency inconsistencies between creation and essence setting.
•
Setters
Solutions
1.
Pass the object's essence on creation
2.
Create objects with their immutable essence.
Examples
•
Some persistence frameworks in static typed languages require an empty constructor.
Sample Code
Wrong
Right
Detection
Any linter can warn this (possible) situation.
Exceptions
•
Stateless objects. Always better solution than static class methods.
More info
Tags
•
Essence
•
Incomplete
•
Mutable
Conclusion
Always create complete objects. Make their essence immutable to endure through time.
Every object needs its essence to be a valid one since inception.
We should read Plato's ideas about immutability and create entities in a complete and immutable way.
These immutable objects favor bijection and survive the passing of time.
Credits
Photo by Brett Jordan in Pexels
In a purely functional program, the value of a [constant] never changes, and yet, it changes all the time! A paradox!
Joel Spolski
This article is part of the CodeSmell Series.
refactoring
cleancode
codesmell