Working Effectively with Android Legacy Code

Android developers face a tough challenge when working with legacy code including God activities, code coupling and issues integrating new features, to name just a few. What other blockers are there to working with legacy code and what are the solutions to such challenges?

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1. WORKING EFFECTIVELY WITH ANDROID LEGACY CODE LUCAS CARO BARRIGA TECHNICAL SPECIALIST IG INDEX @ExpensiveBelly
2. New challenges Good News New job
3. God Objects Bad News Code coupling No tests Hacks, workarounds, “quick fixes”
4. What next?
5. • Rewrite the app from scratch • Maintain the current app • Lose rounds of testing • Last resort Option One
6. • Expensive • Privacy concerns • Hire an agency Option Two
7. Option Three
8. • What is legacy code? Legacy Code “Code without tests” - Michael Feathers
9. • Where do we start? Refactor
10. Hotspots d3js • The parts with high development activity Empear Code Maat
11. • Fractal figures Who has contributed to this code?
12. https://github.com/adamtornhill/FractalFigures Who has contributed to this code? • Ownership models
13. Who should I ask about this code? • Knowledge map showing the main developer (indicated by colour) of each module.
14. Software Visualisation Tools • Code swarm • Code city https://softvis.wordpress.com/tools/
15. • Getting it right - Uncle Bob Solution
16. Robert C. Martin - Clean Architecture on Vimeo Clean Architecture
17. • Many different implementations • https://github.com/android10/Android-CleanArchitecture • https://github.com/Karumi/Rosie • https://github.com/PaNaVTEC/Clean-Contacts • https://github.com/Karumi/KataContactsJava • https://github.com/flipper83/protohipster • Blogs • https://www.novoda.com/blog/hexawhat-architecture/ • http://fernandocejas.com/2014/09/03/architecting-android-the-clean-way/ • https://medium.com/@dmilicic/a-detailed-guide-on-developing-android-apps-using-the- clean-architecture-pattern-d38d71e94029#.hq96s2jxg How to do this in Android
18. Java module. Implementation agnostic. Domain objects, business logic. Modules Android application module. Implementation of the View interfaces. Activities, fragments, custom views, etc. Android library. Network implementation. Storage implementation, etc.
19. • Quicker UI development • No dependency from the server • Happy and unhappy path • Better demos Goals: Offline Mode
20. • Make good use of continuous integration tools • Find bugs as soon as possible Goals: High Code Coverage
21. Don’t do this
22. “Any program feature without automated steps simple doesn’t exist” - Kent Beck Automation
23. • Live documentation Automation Tests • Allows relevant stakeholders to check that requirements are satisfied
24. - Mike Cohn Test Pyramid
25. • Unit tests – JUnit, Mockito • Integration tests – MockWebServer • UI Test – Espresso Test Frameworks
26. • A feature is not complete just because it compiles and runs Best Practices
27. • Refactor in baby steps • Continous delivery • Accurate delivery estimations • Quality above quantity Best Practices
28. Best Practices • Package by feature • Avoid cyclic dependencies • Classes that are used together are packaged together • Classes that change together are packaged together
29. Katas • The Gilded Rose • Kata Mars Rover • Kata Potter • Bank Kata (Sandro Mancuso) • Kata Contacts (Karumi) • Super Heroes (Karumi) • Novoda Dojos
30. Must Read
31. Must Read 2
32. But wait... Programmers don’t read books… …but you should http://blog.codinghorror.com/programmers-dont-read-books-but-you-should/
33. Londroid Book Club The plan: • One book • Six weeks • One meet up To join, contact me on: @ExpensiveBelly or lucasCB84@gmail.com
34. Thank you for listening ? ? ?