Code Smell 94 - Too Many imports

Code Smell 94 - Too Many imports

If your class relies on too many others, it will be coupled and fragile. A long import list is a good indicator.

TL;DR: Don't import too much.

Problems

  • Coupling

  • Single Responsibility Principle violation

  • Low Cohesion

Solutions

  1. Break the class

  2. Hide intermediate accidental implementation

Sample Code

Wrong

import java.util.LinkedList;
import java.persistence;
import java.util.ConcurrentModificationException;
import java.util.Iterator;
import java.util.LinkedList;
import java.util.List;
import java.util.ListIterator;
import java.util.NoSuchElementException 
import java.util.Queue;
import org.fermi.common.util.ClassUtil;
import org.fermi.Data;
//We rely on too many libraries

public class Demo {
   public static void main(String[] args) {

   }
}

import org.fermi.domainModel;
import org.fermi.workflow;

//We rely on few libraries
//and we hide their implementation
//So maybe transitive imports are the same
//but we don't break encapsulation

public class Demo {
   public static void main(String[] args) {

   }
}

Detection

We can set a warning threshold on our linters.

Tags

  • Coupling

  • Ripple Effect

Conclusion

We need to think about dependencies when building our solutions to minimize Ripple Effect.

Relations

More Info

Credits

Photo by Zdeněk Macháček on Unsplash


Fools ignore complexity. Pragmatists suffer it. Some can avoid it. Geniuses remove it.

Alan Perlis


This article is part of the CodeSmell Series.