7 Code Refactoring Techniques in Software Engineering

Code refactoring is the process of improving or upgrading code without affecting the functionality or external behavior of the product or application. It saves on technological costs while improving code efficiency and maintainability. If you do not pay attention to the code restructuring process early on, you will pay for errors later. So don’t skip cleaning up the code.

In the software development process, different developers have different code-writing styles. They make modifications, maintain and enhance the code, and, most of the time, leave it without continual refactoring. Refactored code can lead to code rot, which includes a lot of complexity and confusion in code, such as duplicate code, unhealthy dependencies between classes or packages, poor allocation of class obligations, too many responsibilities per function or class, etc. To avoid all of these concerns, continual refactoring is essential. 

Code Refactoring Techniques in Software Development:

There are various methods and techniques for code refactoring, but in this article, we’ll discuss some of the most popular ones. 

• Red-Green Refactoring: 

The Red-Green-Refactoring approach is central to the practice of test-driven development (TDD), an iterative software development process based on a short development cycle. The basis of this strategy is to write tests before creating the actual codebase.

This procedure can be divided into three steps:

Red: Begin by purposefully developing a failing test to demonstrate its effectiveness in discovering the desired issue.

Green: Write the minimum amount of code required to pass the test quickly, putting speed ahead of code quality or maintainability.

Refactor: Improve the code without changing its functionality, ensuring that the test runs well. This includes tidying up the code to make it more efficient and easier to maintain.

The cycle described above is repeated for each new functionality produced or problem addressed. This is how the strategy promotes the practice of continual code reworking and testing.

• Composing Method: 

During the development process of an application, we frequently write extensive methods in our code. These long methods make your code difficult to comprehend and alter. In these instances, the composition method is most commonly utilized.

In this approach, we apply streamline methods to reduce code duplication. Examples include extracting a method, extracting a variable, inline Temp, replacing Temp with Query, inline method, splitting temporary variables, removing parameter assignments, and so on.

Extraction: Fragmentation is detected and extracted by breaking the code into smaller bits. Following that, we build separate methods for each piece, which is then replaced by a call to the new method. Extraction uses class, interface, and local variables.

Inline: This strategy reduces the number of redundant methods in our software. We detect all calls to the methods and replace them with the method’s content. Following that, we delete the method from our program.

• Simplifying Methods: 

This technique uses two strategies. Let us discuss both of them.

• Simplifying Conditional Expressions Refactoring: 

Conditional statements in programming get increasingly logical and complex over time. To grasp the entire program, simplify your code’s logic. There are numerous approaches to restructure the code and simplify the logic. Some examples include consolidating conditional expressions and duplicating conditional fragments, decomposing conditionals, replacing conditionals with polymorphisms, removing control flags, replacing nested conditionals with guard clauses, and so on.

• Simplifying Method Calls Refactoring: 

This strategy simplifies and clarifies method calls. We improve the interaction between classes and simplify their interfaces.

Examples are adding, removing, and introducing new parameters; replacing the parameter with an explicit method and method call; parameterizing the method; creating a distinct query from the modifier; preserving the entire object; eliminating the setting method, and more. 

• Refactoring by Abstraction: 

This method is also known as the pull-up/push-down method. Abstraction works well for large-scale projects and when attempting to rework enormous amounts of code. This technique uses tactics like extracting, constructing interfaces, and establishing new classes, hierarchy, and class inheritances to reduce repetition and redundancy in your code. It’s vital to remember that abstraction implements large-scale code changes over time rather than all at once, allowing you to keep your systems operational while you make changes in the background.

• Preparatory Refactoring: 

Preparatory refactoring is sometimes described as a combination of software upgrades and refactoring. Whereas other code refactoring strategies are barely focused on refactoring, this technique is used when a developer or software engineer discovers the need for refactoring while creating a new feature. 

• Moving Features Between Objects: 

In this technique, we construct new classes and safely transfer functionality between the old and new ones. We keep the implementation specifics hidden from the public. When should functionality be moved between classes, and how may features be identified for this purpose? 

When you discover that a class has too many responsibilities and too much is going on, or when you discover that a class is redundant and doing nothing in an application, you can shift the code from one class to another and eliminate it completely.

Examples include: relocating a field, extract class, move method, inline class, conceal delegate, adding a foreign method, removing middle man, introducing local extension, etc.

• User Interface Refactoring:

The final code restructuring technique is crucial for improving the usability and aesthetics of software programs. It entails making simple but significant modifications to the user interface (UI) while simultaneously reworking the underlying code. This could include activities like ensuring visual consistency, improving readability, standardizing button sizes for uniformity, and changing color contrasts for easier accessibility. These refinements improve the overall user experience and ensure that the program remains intuitive and efficient. 

Conclusion: 

So, understanding the art of code refactoring is more than a technical ability; it is a mindset that propels software engineering to new heights of brilliance. Software engineers can use the code refactoring approaches outlined to transform complex, convoluted code into elegant, efficient solutions that will stand the test of time. In Software Development by Hashlogics, where we offer top-tier software development services, we recognize how important code restructuring is in creating resilient, scalable, and maintainable software solutions.

Technology embracing refactoring as a key strategy allows our teams to increase code readability, streamline maintenance tasks, and build a culture of continuous progress.