Object-Oriented Reengineering PatternsThe documentation is missing or obsolete, and the original developers have departed. Your team has limited understanding of the system, and unit tests are missing for many, if not all, of the components. When you fix a bug in one place, another bug pops up somewhere else in the system. Long rebuild times make any change difficult. All of these are signs of software that is close to the breaking point.Many systems can be upgraded or simply thrown away if they no longer serve their purpose. Legacy software, however, is crucial for operations and needs to be continually available and upgraded. How can you reduce the complexity of a legacy system sufficiently so that it can continue to be used and adapted at acceptable cost?Based on the authors' industrial experiences, this book is a guide on how to reverse engineer legacy systems to understand their problems, and then reengineer those systems to meet new demands. Patterns are used to clarify and explain the process of understanding large code bases, hence transforming them to meet new requirements. The key insight is that the right design and organization of your system is not something that can be evident from the initial requirements alone, but rather as a consequence of understanding how these requirements evolve. |
Other editions - View all
Object-oriented Reengineering Patterns Serge Demeyer,Stéphane Ducasse,Oscar Nierstrasz Limited preview - 2009 |
Object-Oriented Reengineering Patterns Serge Demeyer,Stéphane Ducasse,Oscar Nierstrasz Limited preview - 2002 |
Common terms and phrases
abstract annotations applied architecture candidate key changes Chapter class diagram Close to Data complex Cons context continued Currency data containers database schema Dave defined deprecated design patterns detect Dotplots duplicated code Employee entities example extract FAMOOS Figure FileList files foreign key functionality identify implementation Incrementally Pattern installation instance variables Intent Interview during Demo introduce invoked Java javadoc JUnit law of Demeter legacy component legacy system lines of code Look maintainers messages method Move Behavior Close object-oriented Pattern 3.4 piece of code plug-in polymorphic problem is difficult problem is feasible provider class Rationale Reengineering Patterns reengineering project Refactor to Understand regression tests represent requirements reverse engineering risk Smalltalk software system Solution solving this problem source code steps Strategy structure subclasses tion tool client Trade-offs Pros Transform Conditionals Type Checks Type Checks Pattern typically verify void Write Tests XDoctor
Popular passages
Page 260 - Webster. Program understanding and the concept assignment problem.