Non-parameterized constructors are a code smell of an invalid object that will dangerously mutate. Incomplete objects cause lots of issues. Non-parameterized constructors are a code smell of an invalid object that will dangerously mutate. Incomplete objects cause lots of issues. invalid TL;DR: Pass the essence to all your objects so they will not need to mutate. 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 Mutability Incomplete objects Concurrency inconsistencies between creation and essence setting. Setters Setters Solutions 😃 Pass the object's essence on creation
Create objects with their immutable essence. Pass the object's essence on creation Create objects with their immutable essence. immutable Refactorings ⚙️ https://hackernoon.com/refactoring-remove-setters-codesmell?embedable=true https://hackernoon.com/refactoring-remove-setters-codesmell?embedable=true https://hackernoon.com/refactoring-016-building-with-the-essence?embedable=true https://hackernoon.com/refactoring-016-building-with-the-essence?embedable=true Examples 📚 Some persistence frameworks in statically-typed languages require an empty constructor. Some persistence frameworks in statically-typed languages require an empty constructor. Sample Code 📖 Wrong 🚫 class AirTicket {
   constructor() {     
  }
} class AirTicket {
   constructor() {     
  }
} Right 👉 class AirTicket {
   constructor(origin,
                destination, 
                arline,
                departureTime,
                passenger) {     

  // ...
  }
} class AirTicket {
   constructor(origin,
                destination, 
                arline,
                departureTime,
                passenger) {     

  // ...
  }
} Detection 🔍 Any linter can warn about this (possible) situation. Exceptions 🛑 Stateless objects. Always a better solution than static class methods. Stateless objects. Always a better solution than static class methods. static class methods Tags 🏷️ Anemic Models Anemic Models Level 🔋 [X] Beginner Why the Bijection Is Important In the MAPPER, objects correspond to real-world entities. MAPPER Real people aren't born nameless and formless, then gradually acquire attributes. You don't meet someone who temporarily has no age or email address. temporarily When you model a person, you should capture their essential attributes at birth, just like reality. model Breaking this bijection by creating hollow objects forces you to represent impossible states. Empty constructors create phantom and invalid objects that don't exist in your domain model, violating the mapping between your code and reality. AI Generation 🤖 AI code generators frequently produce this smell because they often follow common ORM patterns. When you prompt AI to "create a Person class," it typically generates empty constructors with getters and setters. AI tools trained on legacy codebases inherit these patterns and propagate them unless you explicitly request immutable objects with required constructor parameters. AI Detection 🧲 AI tools can detect and fix this smell when you provide clear instructions. You need to specify that objects should be immutable with required constructor parameters. Without explicit guidance, AI tools may not recognize empty constructors as problematic since they appear frequently in training data. Try Them! 🛠 Remember: AI Assistants make lots of mistakes Remember: AI Assistants make lots of mistakes Suggested Prompt: Create an immutable class with required information. Include constructor validation and no setters. Make all fields final and use constructor parameters only Suggested Prompt: Create an immutable class with required information. Include constructor validation and no setters. Make all fields final and use constructor parameters only Without Proper Instructions 📵 ChatGPT
Claude
Perplexity
Copilot
You
Gemini
DeepSeek
Meta AI
Grok
Qwen ChatGPT ChatGPT Claude Claude Perplexity Perplexity Copilot Copilot You You Gemini Gemini DeepSeek DeepSeek Meta AI Meta AI Grok Grok Qwen Qwen With Specific Instructions 👩‍🏫 ChatGPT
Claude
Perplexity
Copilot
You
Gemini
DeepSeek
Meta AI
Grok
Qwen ChatGPT ChatGPT Claude Claude Perplexity Perplexity Copilot Copilot You You Gemini Gemini DeepSeek DeepSeek Meta AI Meta AI Grok Grok Qwen Qwen Conclusion 🏁 Always create complete objects. Make their essence immutable to endure through time. Every object needs its essence to be a valid one since its 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. Relations 👩‍❤️‍💋‍👨 https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-i-xqz3evd https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-i-xqz3evd https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-vi-cmj31om https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-vi-cmj31om https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-viii-8mn3352 https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-viii-8mn3352 https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-ii-o96s3wl4?embedable=true https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-ii-o96s3wl4?embedable=true https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xxiv https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-xxiv More Information 📕 https://hackernoon.com/is-it-crystal-clear-for-everybody-that-a-date-should-not-mutate-wuoy3z03?embedable=true https://hackernoon.com/is-it-crystal-clear-for-everybody-that-a-date-should-not-mutate-wuoy3z03?embedable=true https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-ii-o96s3wl4?embedable=true https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-ii-o96s3wl4?embedable=true 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! In a purely functional program, the value of a [constant] never changes, and yet, it changes all the time! A paradox! Joel Spolski Joel Spolski https://hackernoon.com/400-thought-provoking-software-engineering-quotes?embedable=true https://hackernoon.com/400-thought-provoking-software-engineering-quotes?embedable=true This article is part of the CodeSmell Series. https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-i-xqz3evd https://hackernoon.com/how-to-find-the-stinky-parts-of-your-code-part-i-xqz3evd

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