Sign in Subscribe

Code Smells

Last updated on 

Code smells are indicators of poor quality code that can lead to more serious problems in the future. They are not necessarily errors, but they can make code harder to maintain, more difficult to understand, and can lead to longer development times. Code smells are signs that there is something wrong with the code, but they are not the underlying problems themselves.

Examples of Common Code Smells Here are some of the most common code smells:

  1. Duplicate code: Duplicate code refers to sections of code that are repeated multiple times in the same program. This can make code harder to maintain and debug. When code is duplicated, it can be difficult to make changes to the code because the same change needs to be made in multiple places. In addition, if bugs are found in duplicated code, they need to be fixed in multiple places, which can be time-consuming.
  2. Long methods: Methods that are too long are often a sign of code that is doing too much or is not well organized. When methods are too long, it can be difficult to understand what the method is doing, and it can be difficult to find the part of the code that is causing a problem. Breaking down long methods into smaller, more focused methods can improve readability and maintainability.
  3. Lazy class: Classes that don't do much, or that do too much, can make code difficult to understand. Classes should be focused and well-designed, with a single, clear responsibility. When a class does too much, it can be difficult to understand what the class is responsible for, and it can be difficult to make changes to the code without affecting other parts of the code.
  4. Large classes: Classes that are too big can be difficult to understand and maintain. When a class is too large, it can be difficult to understand what the class is doing and it can be difficult to find the part of the code that is causing a problem. Breaking large classes into smaller, more focused classes can improve the design of the code.
  5. Switch statements: Switch statements can be hard to read and maintain, especially if they are complex or have many cases. When switch statements are complex, it can be difficult to understand what the code is doing, and it can be difficult to make changes to the code. Refactoring switch statements into polymorphic objects or methods can improve the design of the code.
  6. Magic numbers: Magic numbers are hardcoded values in the code that have no meaning, such as a constant value of "10" in a loop. When magic numbers are used, it can be difficult to understand what the code is doing, and it can be difficult to make changes to the code. Using descriptive constant names can make code easier to understand and maintain.
  7. Commented code: Code that is commented out but not removed can be confusing and make it harder to understand the purpose of the code. When commented code is not removed, it can be difficult to know if the code is still needed or if it can be removed. It's best to remove commented code that is no longer needed.
  8. Feature envy: Classes that access the methods and variables of other classes more often than their own can lead to code that is difficult to understand and maintain. When a class accesses the methods and variables of another class too often, it can be difficult to understand what the class is responsible for, and it can be difficult to make changes to the code without affecting other parts of the code. Moving methods and variables to the class that needs them most can improve the design of the code.
In conclusion, code smells are indicators of poor quality code that can lead to more serious problems in the future. They are not errors, but they can make code harder to maintain, more difficult to understand, and can lead to longer development times. Common code smells include duplicate code, long methods, lazy classes, large classes, switch statements, magic numbers, commented code, and feature envy. By recognizing and addressing code smells, developers can improve the quality of their code, making it easier to maintain and understand, and helping to prevent more serious problems from occurring in the future.