Refactoring

Refactoring is where we improve our code quality while maintaining the same functionality. This yields better:

Code Smell

These are issues with the code that aren’t bugs. They are bad coding practices:

Duplicated Code
- We should use generalised classes that we can extend if we need similar, but different, functionality.
Long Methods
- We should split long methods into functions to aid code reuse.
Long Argument Lists
- Collections of data should be wrapped in a type.
- Data that required validation should have it’s own type so that invalid data can never be passed to a function.
Large Classes
- Make sure we are using super-classes properly.
- Generalise functions (pull-up), or specialise (push-down).
  - When generalising methods see if making an interface would be appropriate.
Excessively Long Identifiers
Excessively Short Identifiers
Inappropriate Intimacy
- Where one class writes data directly into another classes attribute.
- We should avoid having any public attributes.