Code as a crime scene

When you need to refactor your code you need be careful about three areas: first found the code to be refactored, secondly be careful with the scope and last but not least, take considerations about your team. During this talk we review these three key points and describe the different approaches a developers can use.

Transcript

1. Code as a crime scene Jorge Juan Barroso Carmona jorge@karumi.com @flipper83 +JorgeJBarroso Android Expert Android GDE
2. Basho. Poet Karumi is the beauty of ordinary things spoken of in a simple way.
4. Adam Tornhill “When you see that I committed a bunch of buggy spaghetti last week, you know it’s because I’m a bad programmer, irresponsible and perhaps even a tad stupid. When you, on the other hand, deliver scrappy code (yes, I know - it’s a hypothetical scenario) you know it’s because you were close to a deadline, had to save the project or just intended it to be a prototype.” Adam Tornhill
5. Why?
6. Timing is part of the development process
7. Programming is problem- solving. And human problem- solving requires a certain degree of experimentation
8. Architecture decay and code entropy
9. Ignorance and bad developers
10. “La deuda técnica es como tener una tarjeta de crédito. Tienes que devolver el dinero y los intereses. Si tiras siempre de la tarjeta de crédito, no vas a poder pagar los intereses y estarás en bancarrota.” Pedro Ureña
11. Finding evidences
12. Run away from trendy styles, intuition, talks or articles
13. Take decisions based on data
14. Repository could be a good tool for take decisions. Code-maat is your friend.
15. number-of-commits,79 number-of-entities,2601 number-of-entities-changed,4582 number-of-authors,27 App Google IO 2014
16. Class sizes. Less size ~= Less responsibilities Cloc for count lines of code.
17. File blank comment code …/iosched/ui/BaseActivity.java 203 175 1185 …/iosched/ui/SessionDetailActivity.java 178 111 995 …arton/disklrucache/DiskLruCacheTest.java 113 37 881 …/iosched/ui/SessionsFragment.java 147 106 875 …/iosched/provider/ScheduleProvider.java 78 128 842
18. Watch out for classes that change frequently, it might be possible that a lot of people are working on it or it has too much responsibility
19. File n-revs android/build.gradle, 14 doc/BUILDING.md, 13 README.md, 9 .travis.yml 9 Wearable/build.gradle, 6 build.gradle 6 android/src/com/google/android/apps/iosched/util/ImageWorker.java, 5 gradle/wrapper/gradle-wrapper.properties, 5 android/src/main/java/com/google/samples/apps/iosched/ui/BaseActivity.java, 5 android/src/main/res/values-it/strings.xml, 5
20. Code complexity based on indentation
21. File num-lines total media max BaseActivity.java 1360 3332 2.45 8 SessionDetailActivity.java 1106 2898 2.62 9 MapInfoWindowAdapter.java 142 221 1.56 5
22. Temporal and hide coupling. Search getInstances()
23. File 1 File2 % couple average-rev SocialStreamFragment.java ImageFetcher.java 100 2 SocialStreamFragment.java ImageCache.java 100 2 ImageCache.java ImageFetcher.java 100 2
24. We can use code analysis tools like SonarQube to find problems.
25. We can use Android Studio to find problems, like DRYs (Don’t repeat yourself)
26. Bug report tool is a good way to find problems.
27. Capturing the bad guy
29. Tests are the only way to make sure that everything keeps working after doing a refactor
30. start always renaming, splitting methods, splitting classes.
31. refactor scope is really important
32. Be careful with eternal changes
33. Listens to everybody before making decisions Echo effect
34. Adjust the team and the communication process for the refactor
35. Ask for opinions from outside (external or other teams)
36. “If you point of me, remember you have 3 fingers pointing at you” Pedro Vicente Gómez
37. Bibliography They’re the cracks! Your Code as a crime scene. Adam Tornhill Working Effectively with legacy code. Michael Feathers Refactoring: Improving the Design of Existing Code. Martin Fowler. Workflows of Refactoring. Martin Fowler. OOP2014. Refactorizar a patrones. Xavi Gost. Refactoring: Where Do I start?. J. B. Rainsberger. Your android app as a crime scene. Pedro Vicente Gomez
38. Find me I am very social! jorge@karumi.com @flipper83 +JorgeJBarroso Questions?