This book introduces the reader to improving a software system's design through refactoring.
It begins with simple refactorings and works its way through complex refactorings by building on the simple refactorings. You will learn how to focus changing the design of their software system and how to prioritize refactorings including how to use various Visual Studio features to focus and prioritize design changes. The book also covers how to ensure quality in light of seemingly drastic changes to a software system. You will also be able to apply standard established principles and patterns as part of the refactoring effort with the help of this book.
Chapter 1, Introducing Refactoring, describes what refactoring is, its importance, and its priority in the software development effort. Comparison to re-writing and what "Technical Debt" is and how refactoring can be used to pay down technical debt is covered in this chapter.
Chapter 2, Improving Code Readability, begins detailing the refactorings built in to Visual Studio and how they can make code more readable. Code smells are introduced, and which code smells apply to readability, and how to detect and refactor them are detailed in this chapter.
Chapter 3, Improving Code Maintainability, continues to detail the refactorings built in to Visual Studio and how they can make code more maintainable. Code smells that apply to maintainability, how to detect and refactor them are detailed in this chapter. The importance of unit testing is covered in this chapter.
Chapter 4, Improving code navigation, continues with simple refactorings and how code can be refactored to improve its navigability in general and takes into account Visual Studio code navigation abilities.
Chapter 5, Improving design correctness, begins detailing complex refactorings. Design principles such as Liskov Substitution and Composition over Inheritance are introduced and how to perform refactorings related to these principles is covered in this chapter.
Chapter 6, Improving class quality, introduces code quality metrics like cohesion and coupling. Principles related to cohesion and coupling are introduced and refactorings that increase cohesion and decrease coupling are covered in this chapter.
Chapter 7, Refactoring to loosely-coupled, expands on coupling from the previous chapter and drills-down on loosely-coupled design. Principles related to loosely-coupled are introduced and complex refactorings related to loosening coupling are covered in this chapter.
Chapter 8, Refactoring to layers, continues with more complex refactorings that involve layered architectures. Typical layers, Model View Presenter, and Repository patterns and how and when to refactor to them are also detailed in this chapter.
Chapter 9, Improving architectural behavior, details complex refactorings to improve architectural behavior. Design behavior patterns, when and how to refactor to them are detailed in this chapter.
Chapter 10, Improving architectural structure, continues with architectural-related complex refactorings. Object-Relational Mapping (ORM) and refactoring Repository implementations are included in this chapter.
Chapter 11, Ensuring Quality with Unit Testing, details the importance of unit testing. How unit testing applies to refactoring, examples of unit testing to support the refactoring effort, and legacy code are also detailed in this chapter.
We will use examples in C# in Visual Studio 2010, but the concepts can be applied to any version of Visual Studio since version 2005.
This book is primarily for developers who want to refactor their code in Visual Studio. However, the book can be used by anyone using Visual Studio. Developers, designers, and architects who are eager to improve the performance of their craft will find this book useful because it details refactoring existing code to use recognized and established patterns and principles to improve code structure and architectural behavior. The book assumes that the reader knows both Visual Studio and C#. No previous knowledge of refactoring is required.
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{
invoiceSubTotal +=
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* (decimal)invoiceLineItem.Quantity);
}
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{
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(float)((decimal)(invoiceLineItem.Price
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* (decimal)invoiceLineItem.Quantity);
}
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