Software refactoring, in the simplest terms, can be defined as a controlled process of improving the internal structure of an existing source code while preserving its external behaviour. It is an integral part of Agile Software Development methods like Scrum, and plays a critical role in ensuring that the software being developed is of high quality, easy to maintain and extend.
This article will discuss why refactoring should be an integral part of any Agile Software development effort, alongside discussing three significant benefits that this technique brings.
Benefit 1: Improved Code Readability and Maintainability
Refactoring helps in simplifying complex code structures by breaking them down into simpler, self-explained sections. This process increases code readability and thereby, the ease of understanding the system for both the team members and any new joiners.
Let’s illustrate this with an example. Consider the following set of codes:
Code before Refactoring:
def calculate(distance, time):
speed = distance/time
return speed
After Refactoring:
def calculate_speed_in_miles_per_hour(distance_in_miles, time_in_hours):
speed_in_miles_per_hour = distance_in_miles / time_in_hours
return speed_in_miles_per_hour
Refactoring here may seem trivial, but it has significantly enhanced the readability of the code. Any developer, even without context, would know what the refactored function does, thanks to the descriptive names.
Benefit 2: Efficient Code Debugging and Error Handling
Refactoring aids in the identification and correction of programming errors, and even simplifies error handling. Code refactoring involves rearranging your code, breaking complex codes into simpler parts, thereby leading to fewer bugs and easier debugging. Whenever an unusual or unexpected behaviour is detected in the code, developers can extract the issue-infected modules, and resolve them without affecting other parts of the system.
Benefit 3: Enhanced Software Performance
Refactoring can help improve the performance of your software. When unnecessary codes are eliminated and complex codes are simplified, the execution becomes faster. This improvement in execution time can make a noticeable difference in the performance of the code. By keeping the code base clean and organized, refactoring reduces the resource usage and makes the software more efficient.
Consider a scenario where a specific function in your software uses a large amount of memory, and this memory usage is found to be due to a complex and nested array within the function’s code. By refactoring this function and simplifying the array structure, the memory usage can be drastically reduced.
To conclude, it’s clear how critical refactoring is in contributing towards the development of high-performing, manageable, error-free software. While it is an ongoing process that requires regular attention, the end all rewards reaped in terms of improved maintainability, streamlined code debugging, and enhanced software performance make this activity integral to any agile software development process. Hence, the Certified Scrum Developers (CSD) would definitely focus and emphasize on the role and advantages of code refactoring in their exam and future profession.
Practice Test
True/False: Refactoring is a part of agile software development process that has no benefits.
- True
- False
Answer: False
Explanation: Refactoring is an integral part of agile development that offers significant benefits including improving the design of the software, making it easier to comprehend, and reducing its complexity.
Choose the correct statement about refactoring:
- A. It is needless as it doesn’t help in debugging.
- B. It only involves changes that affect the internal structure.
- C. It is performed only at the initial stages of development.
Answer: B
Explanation: Refactoring involves changes that don’t affect the external behavior of the software but improve internal structure. It’s not limited to specific stages and also helps in debugging by making the code easier to understand.
Identify the benefits that refactoring in agile software development brings. (Multiple Select)
- A. Reduces complexity
- B. Increases the time taken for development
- C. Makes software design more understandable
- D. Introduce bugs in the software
Answer: A, C
Explanation: Refactoring makes the software design simpler and more comprehensible. It doesn’t increase development time or introduce bugs, rather it aims to prevent these problems.
True/False: Refactoring does not help in maintaining cleaner codebase.
- True
- False
Answer: False
Explanation: By continuously improving the design of code, refactoring helps maintain a clean codebase making it easier to work with over time.
What is not a benefit of refactoring in agile software development?
- A. Easier updates and feature additions
- B. Improved code readability
- C. Slower execution speed
Answer: C
Explanation: Refactoring improves code structure and readability, making it easier for future updates and additions. It does not slow down execution speed.
True/False: Continuous refactoring leads to increased technical debt.
- True
- False
Answer: False
Explanation: On contrary, continuous refactoring helps in reducing technical debt by consistently improving and simplifying the code base.
Is refactoring beneficial for team collaboration in an agile development setting?
- A. Yes
- B. No
Answer: A
Explanation: Refactoring enhances team collaboration in an agile environment because the codes are easier to read and comprehend.
Choose the correct statement:
- A. Refactoring decreases productivity
- B. Refactoring is only about improving coding skills
- C. Refactoring is a useless practice in agile development
- D. None of the above
Answer: D
Explanation: None of these statements are true. Refactoring improves productivity, is not just about coding skills, and is a beneficial practice in agile development.
Refactoring helps in:
- A. Increasing code duplication
- B. Slowing down the software
- C. Predicting future requirements
- D. Spotting and fixing software bugs
Answer: D
Explanation: By improving code readability and structure, refactoring helps in spotting and fixing software bugs more efficiently.
True/False: Refactoring plays no role in improving software performance.
- True
- False
Answer: False
Explanation: While its main purpose is to improve code structure and readability, refactoring can indirectly lead to performance improvements by simplifying algorithms and data structures.
Interview Questions
What is a Sprint Backlog?
A Sprint Backlog is a set of items selected from the Product Backlog to be worked on during a sprint. It’s a forecast of the functionality that will be developed by the team.
How is a sprint backlog used in Scrum framework?
The Sprint Backlog is used as a planning tool for the Development Team to organize its work for the upcoming sprint.
Who is responsible for managing the Sprint Backlog?
The Development Team is responsible for managing the Sprint Backlog.
How does the Sprint Backlog contribute to the transparency in Scrum?
The Sprint Backlog provides a visible, real-time snapshot of the work that the Development Team plans to accomplish during the Sprint.
Can the Sprint Backlog be changed or modified?
Yes, the sprint backlog is a dynamic artifact and can be updated and refined throughout the sprint.
What is the relationship between the Product Backlog and the Sprint Backlog?
The Sprint Backlog is composed of items selected from the Product Backlog for development in a particular sprint.
How does the Sprint Backlog help in measuring progress?
By tracking the completion of backlog items, the team can measure its progress towards the sprint goal.
What happens if all items on a sprint backlog are not completed at the end of a sprint?
Any incomplete backlog items would return to the Product Backlog and may be considered for future sprints.
What role does the Scrum Master play in managing the Sprint Backlog?
The Scrum Master does not manage the Sprint Backlog. This is the responsibility of the Development Team.
How is the Sprint Backlog used in daily Scrum meetings?
The Daily Scrum is a daily stand-up meeting where the Development Team discusses progress and plans for the next 24 hours, using the Sprint Backlog as a guide.
What factors determine the items to be included in the Sprint Backlog?
The items are selected based on the priority set in the Product Backlog and the team’s capacity for the sprint.
How does a Sprint Backlog contribute to the predictability in Scrum?
By providing a detailed plan of the work to be done, the Sprint Backlog can help the team estimate its performance and predict the work that can be accomplished in future sprints.
How does a Sprint Backlog differ from a Product Backlog?
A Product Backlog is a prioritized list of desired product functionality, while a Sprint Backlog is the team’s plan for delivering some of those functionalities in the next Sprint.
Why is it important for the development team to self-manage the Sprint backlog?
Self-management of the Sprint backlog enables the development team to have control over their work, improve their decision-making skills, and increases their commitment and accountability.
How often does the Sprint Backlog change?
The Sprint Backlog is flexible and changes throughout the Sprint based on the team’s understanding of the work and any new information that emerges.