Kotlin Code Smell 4 - Comment Abusers

Kotlin Code Smell 4 - Comment Abusers

Comments are coupled with implementation and hardly maintained.

TL;DR: Leave comments just for important design decisions. Don't explain the obvious!


  • Maintainability

  • Obsolete Documentation

  • Readability

  • Code and comments duplication.


  • Refactor methods.

  • Rename methods to more declarative ones.

  • Break methods into smaller and easier for understanding methods.

  • If a comment describes what a method does, name the method with this description.

  • comment on important design decisions only!


  • Libraries

  • Class Comments

  • Method Comments

Sample Code


 * ChatBotConnectionHelper is used to create connection strings to
 * Bot Platform Use this class with getString() function to get 
 * connection string to the platform.
class ChatBotConnectionHelper(
    var id: String
) {
    // Get Connection String from Chatbot
    fun getString(): String = TODO()


class ChatBotConnectionSequenceGenerator(
    private val name: String
) {
    fun connectionSequence(): Unit = TODO()


Leave comments just for important design decisions. Don't comment on a method with a bad name, rename it. Code changes over time, while documentation rarely does, which causes your code to end up with outdated documentation at best, or wrong documentation at worst.

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