Refactoring is the act of improving the design of existing code without changing the published API.

If you make refactoring (including testing!) a part of your normal programming practice, it will pay off in the simplicity and flexibility your system will have. William Wake shows you how. To learn more, please read What Is Refactoring? by William Wake.

Refactoring is the process of improving the design of code without affecting its external behavior. We refactor so that our code is kept as simple as possible, ready for any change that comes along.

We’ll start with some realistic code and work our way through several refactorings. Our code will become more clear, better designed, and of higher quality.

What do we need for refactoring?

• Our original code
• Unit tests (to ensure we haven’t unwittingly changed the code’s external behavior)
• A way to identify things to improve
• A set of refactorings we know how to apply
• A process to guide us