# Code Smell 10 - Too Many Arguments

*Objects or Functions need too many arguments to work.*

> TL;DR: Don't pass more than three arguments to your functions.

# Problems 😔 

- Low maintainability

- Low Reuse

- Coupling

# Solutions 😃

- Find cohesive relations among arguments

- Create a "context".

- Consider using a [Method Object](https://wiki.c2.com/?MethodObject) Pattern.

- Avoid "basic" Types: strings, arrays, integers, etc. Think on objects.

# Sample Code 📖

## Wrong 🚫

<!-- [Gist Url](https://gist.github.com/mcsee/ea7d32472830d5ea877be1438807fe89) -->

```java
public class Printer {   
  void print(String documentToPrint, 
           String papersize,
           String orientation, 
           boolean grayscales,
           int pagefrom,
           int pageTo,
           int copies,
           float marginLeft,
           float marginRight,
           float marginTop,
           float marginBottom         
        ) {
    }
}
```

## Right 👉

<!-- [Gist Url](https://gist.github.com/mcsee/200a18dd99a76a95155df4cb032b1d10) -->

```java
final public class PaperSize { }
final public class Document { }
final public class PrintMargins { }
final public class PrintRange { }  
final public class ColorConfiguration { }
final public class PrintOrientation { }
// Class definition with methods and properties omitted for simplicity

final public class PrintSetup {
    public PrintSetup(PaperSize papersize,
           PrintOrientation orientation, 
           ColorConfiguration color,
           PrintRange range,
           int copiesCount,
           PrintMargins margins
           ) {}
}

final public class Printer {   
  void print(
         Document documentToPrint, 
         PrintSetup setup        
        ) {
    }
}
```

# Detection 🔍

Most linters warn when the arguments list is too large.

# Exceptions 🛑

- Operations in real-world needing not cohesive collaborators.

# Tags 🏷️

- Bloaters

# Level 🔋

[X] Beginner

# Conclusion 🏁

Relate arguments and group them.
Always favor real-world mappings. Find in real-world how to group the arguments in cohesive objects.

If a function gets too many arguments, some of them might be related to the class construction. This is a design smell too.

# Relations 👩‍❤️‍💋‍👨

%[https://maximilianocontieri.com/code-smell-34-too-many-attributes]

%[https://maximilianocontieri.com/code-smell-13-empty-constructors]

%[https://maximilianocontieri.com/code-smell-87-inconsistent-parameters-sorting]

%[https://maximilianocontieri.com/refactoring-010-extract-method-object]

# Credits 🙏

Photo by [Tobias Tullius](https://unsplash.com/@tobiastu) on [Unsplash](https://unsplash.com/s/photos/loaded)

* * *

This article is part of the CodeSmell Series.

%[https://maximilianocontieri.com/how-to-find-the-stinky-parts-of-your-code]