Re Engineering Legacy Software

Summary As a developer, you may inherit projects built on existing codebases with design patterns, usage assumptions, infrastructure, and tooling from another time and another team. Fortunately, there are ways to breathe new life into legacy projects so you can maintain, improve, and scale them without fighting their limitations. Purchase of the print book includes a free eBook in PDF, Kindle, and ePub formats from Manning Publications. About the Book Re-Engineering Legacy Software is an experience-driven guide to revitalizing inherited projects. It covers refactoring, quality metrics, toolchain and workflow, continuous integration, infrastructure automation, and organizational culture. You'll learn techniques for introducing dependency injection for code modularity, quantitatively measuring quality, and automating infrastructure. You'll also develop practical processes for deciding whether to rewrite or refactor, organizing teams, and convincing management that quality matters. Core topics include deciphering and modularizing awkward code structures, integrating and automating tests, replacing outdated build systems, and using tools like Vagrant and Ansible for infrastructure automation. What's Inside Refactoring legacy codebases Continuous inspection and integration Automating legacy infrastructure New tests for old code Modularizing monolithic projects About the Reader This book is written for developers and team leads comfortable with an OO language like Java or C#. About the Author Chris Birchall is a senior developer at the Guardian in London, working on the back-end services that power the website. Table of Contents PART 1 GETTING STARTED Understanding the challenges of legacy projects Finding your starting point PART 2 REFACTORING TO IMPROVE THE CODEBASE Preparing to refactor Refactoring Re-architecting The Big Rewrite PART 3 BEYOND REFACTORING—IMPROVING PROJECT WORKFLOWAND INFRASTRUCTURE Automating the development environment Extending automation to test, staging, and production environments Modernizing the development, building, and deployment of legacy software Stop writing legacy code!

Object-Oriented Reengineering Patterns collects and distills successful techniques in planning a reengineering project, reverse-engineering, problem detection, migration strategies and software redesign. This book is made available under the Creative Commons Attribution-ShareAlike 3.0 license. You can either download the PDF for free, or you can buy a softcover copy from lulu.com. Additional material is available from the book's web page at http://scg.unibe.ch/oorp

Reengineering Legacy Software Systems shows how to evaluate systems, identify the problems, and fix them without starting over from scratch. It focuses on identifying the positive aspects of the system and building on them, instead of getting bogged down with what doesn't work. It covers the principles of reengineering and then shows how to specifically apply them to the problem of software engineering. Reengineering Legacy Software Systems fits in with system engineering books and looks at all the current tools such as CASE, rule-based technology and object technology. Information technology managers and software engineers are faced with the problem of having to solve problems without spending a lot of money and this book will be a great resource for those people. Mix of theory and practice. Specific to software, emphasizing techniques and tools required. Incorporates case studies.

Application Software Re-engineering is about reorganizing and modifying existing software systems to make them more maintainable and user friendly. It also powerfully dwells on the aspects of general Application Software Reengineering across variou.

Re-engineering AS/400 Legacy Applications and companion CD ROM provide a tutorial aimed at showing you how to modernize your applications by taking you step by step through the re-engineering of a sample application. Author Paul Tuohy covers conversion of RPG IV programs, as well as re-engineering them to take full advantage of RPG IV and ILE. He also covers triggers, referential integrity, and APIs so that your applications can take advantage of all the new technology that is available today. This book will be a valuable aid as you evaluate your legacy applications and then move into re- engineering.

Software process reengineering has become highly visible over the past several years. Efforts are being undertaken by organizations of all types and sizes as they attempt to deal with the challenges of quality, complexity and competitiveness. As an emerging technology, the effectiveness and potential impact of process improvement efforts have been debated, but not fully tested or validated. At the very core of this technological evolution is the idea that the quality of a software product is highly dependent on the quality of the process used for its development. Successful Software Reengineering examines the most recent theories, models, approaches and processes involved with the concept of software improvement and reengineering.

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 great challenge of reverse engineering is recovering design information from legacy code: the concept recovery problem. This monograph describes our research effort in attacking this problem. It discusses our theory of how a constraint-based approach to program plan recognition can efficiently extract design concepts from source code, and it details experiments in concept recovery that support our claims of scalability. Importantly, we present our models and experiments in sufficient detail so that they can be easily replicated. This book is intended for researchers or software developers concerned with reverse engineering or reengineering legacy systems. However, it may also interest those researchers who are interested using plan recognition techniques or constraint-based reasoning. We expect the reader to have a reasonable computer science background (i.e., familiarity with the basics of programming and algorithm analysis), but we do not require familiarity with the fields of reverse engineering or artificial intelligence (AI). To this end, we carefully explain all the AI techniques we use. This book is designed as a reference for advanced undergraduate or graduate seminar courses in software engineering, reverse engineering, or reengineering. It can also serve as a supplementary textbook for software engineering-related courses, such as those on program understanding or design recovery, for AI-related courses, such as those on plan recognition or constraint satisfaction, and for courses that cover both topics, such as those on AI applications to software engineering. ORGANIZATION The book comprises eight chapters.