Martin Fowler's guide to reworking bad code into well-structured code

Refactoring improves the design of existing code and enhances software maintainability, as well as making existing code easier to understand. Original Agile Manifesto signer and software development thought leader, Martin Fowler, provides a catalog of refactorings that explains why you should refactor; how to recognize code that needs refactoring; and how to actually do it successfully, no matter what language you use.

• Refactoring principles: understand the process and general principles of refactoring
• Code smells: recognize bad smells in code that signal opportunities to refactor
• Application improvement: quickly apply useful refactorings to make a program easier to comprehend and change
• Building tests: writing good tests increases a programmer's effectiveness
• Moving features: an important part of refactoring is moving elements between contexts
• Data structures: a collection of refactorings to organize data, an important role in programs
• Conditional Logic: use refactorings to make conditional sections easier to understand
• APIs: modules and their functions are the building blocks of our software, and APIs are the joints that we use to plug them together
• Inheritance: it is both very useful and easy to misuse, and it's often hard to see the misuse until it's in the rear-view mirror---refactorings can fix the misuse

Examples are written in JavaScript, but you shouldn't find it difficult to adapt the refactorings to whatever language you are currently using as they look mostly the same in different languages.

Whenever you read [Refactoring], it's time to read it again. And if you haven't read it yet, please do before writing another line of code. -David Heinemeier Hansson, Creator of Ruby on Rails, Founder & CTO at Basecamp

Any fool can write code that a computer can understand. Good programmers write code that humans can understand. -M. Fowler (1999)

Build, Measure and Learn as Steve Blank says: is much more elaborate than putting software into production to see if it works. The Lean Startup movement is very promising, but for many teams it ends up translating into an important question: Yeah, but what to build ?In ThoughtWorks, our response has been a process called an inception. We gather together a good sample of the people who will be affected by the product and have an intensive session to set an initial direction, using a series of exercises focusing on collaboration and the capture of broad goals. We don't attempt a detailed specification, as that is exactly the kind of thing that becomes out of date as soon as code hits production. But we do want to understand what kind of outcomes we are hoping for, the features that we think will drive these outcomes, and how to assess the effectiveness of our product.With The Lean Inception, Paulo has captured his experience in running these inceptions over the last decade. In particular it's focused on his work to boil the inception down to its essence, concentrating the activity on a single, if very intensive, week of work. Paulo shares how he makes this work, through writing a product vision, capturing personas, understanding the user journeys, and developing high-level features. The result isn't a detailed plan of work, which we find quickly rots into irrelevance. It is a guiding set of goals to set us off in the right direction. It doesn't plan out a final product, with all the features that our users will need, instead it focuses on an initial product that we can release and learn from - the Minimum Viable Product. - Martin Fowler, Chief Cientist at ThoughtWorks

When carefully selected and used, Domain-Specific Languages (DSLs) may simplify complex code, promote effective communication with customers, improve productivity, and unclog development bottlenecks. In Domain-Specific Languages, noted software development expert Martin Fowler first provides the information software professionals need to decide if and when to utilize DSLs. Then, where DSLs prove suitable, Fowler presents effective techniques for building them, and guides software engineers in choosing the right approaches for their applications.
This book's techniques may be utilized with most modern object-oriented languages; the author provides numerous examples in Java and C#, as well as selected examples in Ruby. Wherever possible, chapters are organized to be self-standing, and most reference topics are presented in a familiar patterns format.

Armed with this wide-ranging book, developers will have the knowledge they need to make important decisions about DSLs--and, where appropriate, gain the significant technical and business benefits they offer.

The topics covered include:

- How DSLs compare to frameworks and libraries, and when those alternatives are sufficient

- Using parsers and parser generators, and parsing external DSLs

- Understanding, comparing, and choosing DSL language constructs

- Determining whether to use code generation, and comparing code generation strategies

- Previewing new language workbench tools for creating DSLs

The practice of enterprise application development has benefited from the emergence of many new enabling technologies. Multi-tiered object-oriented platforms, such as Java and .NET, have become commonplace. These new tools and technologies are capable of building powerful applications, but they are not easily implemented. Common failures in enterprise applications often occur because their developers do not understand the architectural lessons that experienced object developers have learned.

Patterns of Enterprise Application Architecture is written in direct response to the stiff challenges that face enterprise application developers. The author, noted object-oriented designer Martin Fowler, noticed that despite changes in technology--from Smalltalk to CORBA to Java to .NET--the same basic design ideas can be adapted and applied to solve common problems. With the help of an expert group of contributors, Martin distills over forty recurring solutions into patterns. The result is an indispensable handbook of solutions that are applicable to any enterprise application platform.

This book is actually two books in one. The first section is a short tutorial on developing enterprise applications, which you can read from start to finish to understand the scope of the book's lessons. The next section, the bulk of the book, is a detailed reference to the patterns themselves. Each pattern provides usage and implementation information, as well as detailed code examples in Java or C#. The entire book is also richly illustrated with UML diagrams to further explain the concepts.

Armed with this book, you will have the knowledge necessary to make important architectural decisions about building an enterprise application and the proven patterns for use when building them.

The topics covered include

- Dividing an enterprise application into layers

- The major approaches to organizing business logic

- An in-depth treatment of mapping between objects and relational databases

- Using Model-View-Controller to organize a Web presentation

- Handling concurrency for data that spans multiple transactions

- Designing distributed object interfaces

More than 300,000 developers have benefited from past editions of UML Distilled . This third edition is the best resource for quick, no-nonsense insights into understanding and using UML 2.0 and prior versions of the UML.

Some readers will want to quickly get up to speed with the UML 2.0 and learn the essentials of the UML. Others will use this book as a handy, quick reference to the most common parts of the UML. The author delivers on both of these promises in a short, concise, and focused presentation.

This book describes all the major UML diagram types, what they're used for, and the basic notation involved in creating and deciphering them. These diagrams include class, sequence, object, package, deployment, use case, state machine, activity, communication, composite structure, component, interaction overview, and timing diagrams. The examples are clear and the explanations cut to the fundamental design logic. Includes a quick reference to the most useful parts of the UML notation and a useful summary of diagram types that were added to the UML 2.0.

If you are like most developers, you don't have time to keep up with all the new innovations in software engineering. This new edition of Fowler's classic work gets you acquainted with some of the best thinking about efficient object-oriented software design using the UML--in a convenient format that will be essential to anyone who designs software professionally.

This innovative book recognizes the need within the object-oriented community for a book that goes beyond the tools and techniques of the typical methodology book. In Analysis Patterns: Reusable Object Models, Martin Fowler focuses on the end result of object-oriented analysis and design--the models themselves. He shares with you his wealth of object modeling experience and his keen eye for identifying repeating problems and transforming them into reusable models. Analysis Patterns provides a catalogue of patterns that have emerged in a wide range of domains including trading, measurement, accounting and organizational relationships.

Recognizing that conceptual patterns cannot exist in isolation, the author also presents a series of support patterns that discuss how to turn conceptual models into software that in turn fits into an architecture for a large information system. Included in each pattern is the reasoning behind their design, rules for when they should and should not be used, and tips for implementation. The examples presented in this book comprise a cookbook of useful models and insight into the skill of reuse that will improve analysis, modeling and implementation.