Refactoring Improving The Design Of Existing Code

The Definitive Refactoring Guide, Fully Revamped for Ruby With refactoring, programmers can transform even the most chaotic software into well-designed systems that are far easier to evolve and maintain. What’s more, they can do it one step at a time, through a series of simple, proven steps. Now, there’s an authoritative and extensively updated version of Martin Fowler’s classic refactoring book that utilizes Ruby examples and idioms throughout–not code adapted from Java or any other environment. The authors introduce a detailed catalog of more than 70 proven Ruby refactorings, with specific guidance on when to apply each of them, step-by-step instructions for using them, and example code illustrating how they work. Many of the authors’ refactorings use powerful Ruby-specific features, and all code samples are available for download. Leveraging Fowler’s original concepts, the authors show how to perform refactoring in a controlled, efficient, incremental manner, so you methodically improve your code’s structure without introducing new bugs. Whatever your role in writing or maintaining Ruby code, this book will be an indispensable resource. This book will help you Understand the core principles of refactoring and the reasons for doing it Recognize “bad smells” in your Ruby code Rework bad designs into well-designed code, one step at a time Build tests to make sure your refactorings work properly Understand the challenges of refactoring and how they can be overcome Compose methods to package code properly Move features between objects to place responsibilities where they fit best Organize data to make it easier to work with Simplify conditional expressions and make more effective use of polymorphism Create interfaces that are easier to understand and use Generalize more effectively Perform larger refactorings that transform entire software systems and may take months or years Successfully refactor Ruby on Rails code

Refactoring is gaining momentum amongst the object oriented programming community. It can transform the internal dynamics of applications and has the capacity to transform bad code into good code. This book offers an introduction to refactoring.

Fully Revised and Updated–Includes New Refactorings and Code Examples “Any fool can write code that a computer can understand. Good programmers write code that humans can understand.” —M. Fowler (1999)For more than twenty years, experienced programmers worldwide have relied on Martin Fowler’s Refactoring to improve the design of existing code and to enhance software maintainability, as well as to make existing code easier to understand. This eagerly awaited new edition has been fully updated to reflect crucial changes in the programming landscape. Refactoring, Second Edition, features an updated catalog of refactorings and includes JavaScript code examples, as well as new functional examples that demonstrate refactoring without classes. Like the original, this edition explains what refactoring is; why you should refactor; how to recognize code that needs refactoring; and how to actually do it successfully, no matter what language you use. Understand the process and general principles of refactoring Quickly apply useful refactorings to make a program easier to comprehend and change Recognize “bad smells” in code that signal opportunities to refactor Explore the refactorings, each with explanations, motivation, mechanics, and simple examples Build solid tests for your refactorings Recognize tradeoffs and obstacles to refactoring Includes free access to the canonical web edition, with even more refactoring resources. (See inside the book for details about how to access the web edition.)

In 1994, Design Patterns changed the landscape of object-oriented development by introducing classic solutions to recurring design problems. In 1999, Refactoring revolutionized design by introducing an effective process for improving code. With the highly anticipated Refactoring to Patterns , Joshua Kerievsky has changed our approach to design by forever uniting patterns with the evolutionary process of refactoring. This book introduces the theory and practice of pattern-directed refactorings: sequences of low-level refactorings that allow designers to safely move designs to, towards, or away from pattern implementations. Using code from real-world projects, Kerievsky documents the thinking and steps underlying over two dozen pattern-based design transformations. Along the way he offers insights into pattern differences and how to implement patterns in the simplest possible ways. Coverage includes: A catalog of twenty-seven pattern-directed refactorings, featuring real-world code examples Descriptions of twelve design smells that indicate the need for this book’s refactorings General information and new insights about patterns and refactoring Detailed implementation mechanics: how low-level refactorings are combined to implement high-level patterns Multiple ways to implement the same pattern–and when to use each Practical ways to get started even if you have little experience with patterns or refactoring Refactoring to Patterns reflects three years of refinement and the insights of more than sixty software engineering thought leaders in the global patterns, refactoring, and agile development communities. Whether you’re focused on legacy or “greenfield” development, this book will make you a better software designer by helping you learn how to make important design changes safely and effectively.

& Most software practitioners deal with inherited code; this book teaches them how to optimize it & & Workbook approach facilitates the learning process & & Helps you identify where problems in a software application exist or are likely to exist

Get more out of your legacy systems: more performance, functionality, reliability, and manageability Is your code easy to change? Can you get nearly instantaneous feedback when you do change it? Do you understand it? If the answer to any of these questions is no, you have legacy code, and it is draining time and money away from your development efforts. In this book, Michael Feathers offers start-to-finish strategies for working more effectively with large, untested legacy code bases. This book draws on material Michael created for his renowned Object Mentor seminars: techniques Michael has used in mentoring to help hundreds of developers, technical managers, and testers bring their legacy systems under control. The topics covered include Understanding the mechanics of software change: adding features, fixing bugs, improving design, optimizing performance Getting legacy code into a test harness Writing tests that protect you against introducing new problems Techniques that can be used with any language or platform—with examples in Java, C++, C, and C# Accurately identifying where code changes need to be made Coping with legacy systems that aren't object-oriented Handling applications that don't seem to have any structure This book also includes a catalog of twenty-four dependency-breaking techniques that help you work with program elements in isolation and make safer changes.

The first refactoring guide specifically for Ruby - one of today's fastest growing programming languages Co-authored by Martin Fowler based on his legendary Refactoring, which started the refactoring revolution.