Working Effectively with Legacy Code

Chapter 21: I’m Changing the Same Code All Over the Place

This can be one of the most frustrating things in legacy systems. You need to make a change, and you think, “Oh, that’s all.” Then you discover that you have to make the same change over and over again because there are about a dozen places with similar code in your system. You might get the sense that if you reengineered or restructured your system, you might not have this problem, but who has time for that? So you are left with another sore point in the system, something that adds up to general yuckiness.

If you know about refactoring, you’re in a better position. You know that removing duplication doesn’t have to be a grand effort such as in reengineering or re-architecting. It’s something ...