Check out the video of the presentation: http://www.youtube.com/watch?v=WpKb1XqSiUs

1. Testing and Refactoring
Legacy Code
Sandro Mancuso
@sandromancuso
craftedsw.blogspot.com

2. What is this session about?

3. Business Requirements
Imagine a social networking website for
travellers
• You need to be logged in to see the content
• You need to be a friend to see someone else’s
trips

4. Legacy Code Rules
• You cannot change production code if not
covered by tests
– Just automated refactoring (via IDE) is allowed, in
case it is needed for writing a test

5. Show me the code

6. Start refactoring from
deepest to shortest
branch
Start testing from
shortest to
deepest branch
Working with Legacy Code Tips

7. Trip Service - Problems
TripService
+findTripsByUser(User) : List<Trip>
<<Singleton>>
UserSession
+getInstance() : UserSession
+getLoggedUser() : User
TripDAO
+findTripsByUser(User) : List<Trip>

8. Let’s write some code

9. Start refactoring from
deepest to shortest
branch
Start testing from
shortest to
deepest branch
Working with Legacy Code Tips

10. Craftsmen at work
• Write readable and maintainable code and tests
– Code must express business rules
• Strive for simplicity
• Know your tools well (i.e. frameworks, shortcuts)
• Work in small and safe increments
– Commit often
• Embrace changes, be brave
• Boy scout rule / No broken windows

11. Thanks
Sandro Mancuso
@sandromancuso
craftedsw.blogspot.com
https://github.com/sandromancuso/trip-service-kata
leanpub.com/socra