define refactoring.

Concepts

Refactoring is a disciplined and controlled technique for improving the structure of existing code, while preserving its external behavior. It’s an essential element of Agile practices, especially for those pursuing the Certified Scrum Developers (CSD) exam. The concept of refactoring is crucial for Agile and Scrum methodologies, as it ensures that the code maintains high quality and adaptability in the context of changing requirements.

Understanding Refactoring

The heart of refactoring is a sequence of small, behavior-preserving transformations where each modification slightly improves the program’s structure, making the next modification easier. Thus, refactoring can be seen as an iterative and incremental process of enhancing the design of an existing code base.

This concept is based on the understanding that software development should be flexible and responsive to change. Rather than working on large, monolithic chunks of work, refactoring encourages developers to constantly improve and refine their code. The objective here is to make the code more readable, maintainable and extendable, while preserving its functionality.

Benefits of Refactoring

Refactoring provides several tangible benefits include:

Improved Code Readability: Refactoring makes the code more understandable to others, making it easier for future maintenance.
Reduced Complexity: It simplifies the structure of the software, making it easier to navigate.

Enhanced Code Performance: Refactoring may help improve the program’s performance by reariving and enhancing code.
Easier Bug Detection: Cleaner, well-organized code often helps highlight any hidden bugs or redundancies.

Here’s a simple comparison illustrating the power of refactoring:

Before Refactoring	After Refactoring
Complex and cluttered code	Simplified and structured code
Difficulty in understanding the code structure	Improved readability
High possibility of hidden bugs	Bugs are easier to detect
Difficulty in making changes or additions	Extended functionality is easier

Examples of Refactoring

One common example of refactoring is the ‘Extract Method’ strategy. This involves taking a code fragment that can be grouped together, moving it into a separate new method, and replacing the old code with a call to the new method.

Before:

void printOwing() {
printBanner();

// print details
System.out.println (“name: ” + _name);
System.out.println (“amount: ” + getOutstanding());
}

After:

void printOwing() {
printBanner();
printDetails(getOutstanding());
}

void printDetails (double outstanding) {
System.out.println (“name: ” + _name);
System.out.println (“amount: ” + outstanding);
}

In summary, refactoring plays a pivotal role in Agile and Scrum methodologies. It encourages continuous improvement, resulting in more readable, maintainable and extendable code. It also improves competency in detecting and fixing bugs, ensuring better overall software quality. It’s, therefore, a critical component for any aspirant preparing for the Certified Scrum Developers (CSD) exam.

Answer the Questions in Comment Section

True or False: Refactoring involves altering a system’s internal structure without changing its behavior or introducing new features.

True

False

Answer: True

Explanation: The fundamental purpose of refactoring is to make the system’s code easier to understand and modify without affecting its behavior or adding new features.

What is the primary purpose of refactoring?

A. To add new features to a software system.
B. To remove bugs and errors from a software system.
C. To enhance the internal structure of a software system without altering its external behavior.

Answer: C. To enhance the internal structure of a software system without altering its external behavior.

Explanation: The objective of refactoring is to improve the software system’s internal structure; it does not primarily aim to add new features or fix bugs.

True or False: Refactoring is the same as debugging.

True

False

Answer: False

Explanation: Refactoring and debugging are different; refactoring is done to improve the code structure without altering the functionality, while debugging is done to find and fix errors.

In the context of refactoring, what is ‘Code Smell’?

A. A type of programming error.
B. An indication that code might need refactoring.
C. The smell resulted from burning computer chips.

Answer: B. An indication that code might need refactoring.

Explanation: ‘Code smell’ is a term used in programming to refer to a symptom in the source code that possibly indicates a deeper problem. It suggests the code should be refactored.

What does ‘Red-Green-Refactor’ mean in Agile Development?

A. Stop-Go-Code

B. Write tests, make them pass, clean up the code.
C. Error, Success, Debugging

Answer: B. Write tests, make them pass, clean up the code.

Explanation: ‘Red-Green-Refactor’ means first writing a test that fails (red), then writing the code to make the test pass (green), followed by cleaning up the code (refactor).

True or False: Refactoring can also be performed on the design of software, not only on the source code.

True
False

Answer: True

Explanation: Refactoring can be performed on different levels of software development, including design, in order to improve the system structure.

The procedure of refactoring should significantly impact the system’s behavior.

A. True

B. False

Answer: B. False

Explanation: One of the key principles of refactoring is that it should not alter the overall behavior of the system.

Refactoring can help in:

A. Enhancing code readability
B. Making the code easier to maintain
C. Reducing the complexity of the code.

D. All of the above

Answer: D. All of the above.

Explanation: Refactoring improves the code quality by enhancing its readability, maintainability, and reducing complexity.

Risk of introducing bugs is high during the refactoring process.

A. True
B. False

Answer: B. False

Explanation: If done correctly, with adequate test coverage, the risk of introducing new errors during refactoring is low because the behavior of the software should not be changed.