I need to refactor my code. Guide for code refactoring: When, Why, and How

September 6th, 2021

Evgenia Kuzmenko KITRUM Brand ManagerEvgenia Kuzmenko

Code refactoring is a method used in dev-ops to improve a code by making it easily read, quality build, and better structure, that enables the addition of features that are new and improved which makes for higher quality functionality and improves bug tracking and correction.

It enables the cleaning of old software by making the old codes elegant without changing the purpose of the old software and this makes for purposeful software refactoring. This process helps for truly viable projects, as it gives benefits such as improving a bad design, or an excellent design that is seemingly old, improved scalability, reduced code defects, higher software performance, better security, and swifter performance, etc. 

Although the feedback about the benefits of code refactoring is often not instantaneous, it is visibly felt by the adopters and users of the software more so over time. It is a situation of working over an old horse to improve its agility, fluidity, stability, etc.

Why Are Software Codes ReFactored? 

The “why” about code refactoring is an interesting question and the answers to this are bountiful. As the project cycle for software projects go, it begins with the elicitation of technical requirements, filtering of user retirements, implementation of the features from the “must-have” to the “could have” features to give it a range of functionality. 

This is often how the project process goes, but as we approach an age where the agile method of software development is pervasive, we get genuine reasons to carry out code refactoring due to problems such as:

  • Smelly Code
  • Software Improvement 
  • Software Decay
  • Bug Tracking

Smelly Code: Smelly code means an indication of bigger software trouble, but these are often overlooked as their effects are not strong, but there are times it affects the software integrity, and this occurs as a result of using codes that are duplicate, bad codes, longer code in place of shorter codes, wrong code placement, etc, and this happens as a result of tight project deadlines that follows software projects and this answers one of the “why” for refactoring a software.

Software Trend: it is common with the continual advancement in information technology that there is often a change in trend and this applies to software programs. An elegant software today could become outdated tomorrow as new functionalities appear and there is an urgent need to update the current code to add these newer features, use fewer codes than was previously possible, etc. 

By refactoring software code in line with the trend, it gives the possibility of adding newer features in line with the system and users demand, better bug to code ratio, better readability of code, better project accessibility, documentation, etc.

Software Decay: As the name implies, it suggests corruption in how the software performs over time that leads to a reduction in the response of software functionality, makes it mostly unusable and creates the urgent need for a lift in the capability of the software.

To correct a code decay is to refactor the codes used in the software to create new functions that give the previous codes a significant boost through enhancing the compatibility within the code, creation of new documentation for the codes, revision of the old codes, etc.

Bug Tracking: Software programs are often riddled with bugs and this affects the performance of codes used in the software. It answers one of the “why” for refactoring a code as the codes used for the software are fully reviewed and revised for optimal performance and reduction of the bug to code ratio within better acceptable standards. 

When Do We Need to Refactor A Software?

There are 4 agreed periods generally for refactoring software and these are:

  • Software Release 
  • Software maintenance period, 
  • Before Launch
  • Before the addition of new functionalities to a software 

Software Release: The release of the software is often hurried as deadlines are rarely met in software projects, and this means that codes are hurriedly written and checks are not properly done for bugs, and other system issues are not traced. A code refactoring is advised after launch for a revision of codes to ensure that the software’s stability and integrity are not compromised in any way.

Software maintenance period: This is a time set aside for a code review to ensure that the software is refactored as at when due. It is a proactive decision by a software team to come together at regular intervals and look at the codes running the system, to trace any issues and judge the scale of the performance of the software. It is adopted often as a way to ensure that software decay does not happen over time and updates which are released are always optimal.

Before Launch: This might seem intuitive but it is not. It is generally known that before a launch, coders often hurry their codes to release a timely product, and this means that time is not devoted for a last-minute check on the codes used for the software. By refactoring the software, there is the possibility of increasing benefits for that software no matter how little, and this could be carried out by just 5% of the original software team.

Before the addition of new functionalities to software: It is unwise to add new functions and features to a software product without conducting code refactoring, as these new features might work contrary to the expectations from the software. By performing a code cleanse, issues that might be there are found out, bugs are tracked, confirmation of software performance, etc and this leads to a better appreciation of the new software functionalities added. 

Some of the suggestions above might seem unusual given how close the period of release is to the time suggested for refactoring. But as with most software problems, a technical issue not resolved today is often met with a major loss. 

When Do We Not Need to Refactor a Code?

Code refactoring is not necessary nor needed when software that is just released works better than expected or even just fine, or when a code revision and correction will lead to confusion for the members of the software team as against bringing more cohesion and practical benefits, when it causes costly time wastage, inflate the cost by much more, a software becomes dead, etc. 

code refactoring

How to Approach Code Refactoring

There are lots of ways to approach code refactoring, but only a couple of those will be mentioned, but one thing should be noted, that regardless of the approach, the best way is by little steps, and since the “when” and “why” has been answered, it is time to explain the “how”. These 4 processes will be explained below:

  • The Refractor, Red, Green
  • The Simplification Method
  • Refactoring By Abstraction 
  • Primary Refactoring
  • The Refactoring of Objects Between Moving Classes

The Refactor, Red, Green: This process is synonymous with the methodology of agile, and it follows a test led development, and what this means is that the software development is driven by tests, and this can be explained in 3 steps:

RED Stage: Use a test case as a guide for development and make the testing fail

GREEN Stage: The development of a code that just marks the test as passed.

REFACTOR Stage: Revise and improve the written code.

The Simplification Method: This is another approach to software refactoring that has a fit as every written code for a software code ages and this creates a need to simplify the reasoning behind the code, and to do so involve changing the interaction among classes, the removal and addition of new framework for the software, distinct new methods, etc. 

Refactoring By Abstraction: The process of refactoring by abstraction is often suggested when it involves a large-scale change to software in a way that is not rushed, and the software is still made to function while abstraction is ongoing. 

The end goal is to reduce the complex problems that might arise as a result of code merging and to reduce the number of codes that are duplicated. Abstraction touches on the classes of legacy code, removal, etc, and the Push-up and the Push-Down methods are notable examples. 

Method of pull up: This method eradicates repeat codes by pulling the parts of codes into a superclass.

Method of pull-down: This method eradicates repeat codes by opposite action of pulling parts of codes to subclasses, unlike the pull-up method.

Primary Refactoring: This is a process of software refactoring that is used to drive the addition of new functionality to software and this is done together with the release of a software update, and the debt due to technical requirement is reduced and the codes are refactored. 

This method is beneficial as it saves time consumption, achieves two objectives simultaneously, and creates room for improvement in another aspect of the organization, other areas where more efforts can be devoted, etc. 

The refactoring of objects between moving features: This method of code refactoring means using a technique that enables functionality to be in a choice class, whether new or old depending on the activity in the class, and this method is often executed without the information being known locally.

Some interesting Tips On Code Refactoring

There are different ways software can be refactored and there are plenty of recommendations on how to go about it, but a look at the agile methodology points to an approach of small but tangible steps, and it is adopted by software developers for refactoring software codes, and some of the tips gleaned from the agile framework and other approaches  are:

  • Work break down to feasible tasks
  • Review of need for refactoring before an update release
  • Test led development
  • Focus on quality 
  • Cohesion, Collaboration and Communication.