Have you encountered classes without behavior? Classes are their behavior.
TL;DR: Remove all empty classes.
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Bijection Fault
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Namespace Polluting
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Classes used as DTOs
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Classes used as global references
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Remove the classes and replace them with objects instead.
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If your classes are Anemic Exceptions, remove them.
Many developers still think classes are data repositories.
They couple different behavior concept with returning different data.
class ShopItem {
code() { }
description() { }
}
class BookItem extends ShopItem {
code() { return 'book' }
description() { return 'some book'}
}
// concrete Class has no real behavior, just return different 'data'class ShopItem {
constructor(code, description) {
// validate code and description
this._code = code;
this._description = description;
}
code() { return this._code }
description() { return this._description }
// Add more functions to avoid anemic classes
// getters are also code smells, so you need to iterate it
}
bookItem = new ShopItem('book', 'some book);
// create more items[X] Automatic
Several linters warn us of empty classes.
We can also make our own scripts using metaprogramming.
- Behavior
Classes are what they do, their behavior.
Empty classes do nothing.
Code Smell 26 - Exceptions Polluting
Code Smell 60 - Global Classes
Code Smell 136 - Classes With just One Subclass
Photo by Kelly Sikkema on Unsplash
An error arises from treating object variables (instance variables) as if they were data attributes and then creating your hierarchy based on shared attributes. Always create hierarchies based on shared behaviors, side.
David West
Software Engineering Great Quotes
This article is part of the CodeSmell Series.