This document summarizes Sonar, an open source platform for managing code quality. Sonar aggregates various tools to analyze code quality metrics like static analysis, duplicate code detection, and code coverage. It provides a web-based portal with visualizations of code quality statistics, violations, and technical debt over time. The document encourages trying out Sonar to improve code quality and discusses prioritizing areas to start like increasing test coverage or removing duplicate code.

1. Do Great Code!
Samuel Langlois, 17-Jan-2013

2. Sonar
• A platform to manage code quality
• Free, open source, LGPL, web-based portal
• Backed by
• Aggregates well-known tools
– Static analysis (PMD, findbugs, Checkstyle)
– Duplicate code (Squid, CPD)
– Code coverage (Cobertura, JaCoCo)
(name change soon?)

3. Sonar @ Alfresco
• http://sonar.alfresco.com
• Open access, LDAP authentication coming
• Contains the following projects:
– Enterprise HEAD (Maven build)
– CLOUD1 (Maven build)
– Benchmark
– Android SDK and App
– …

4. Sonar portal

5. Sonar – Basic statistics

6. Drilling down
• Whole project
– Project/module
• Java package
– Java class

7. Sonar – Duplications

8. Sonar – Package tangle

9. Sonar - Coverage

10. Clouds

11. Sonar - Violations

12. Violation examples
• Impossible cast

13. Violation examples
• Dead store

14. Violation examples
• Dead store

15. Violation examples
• Redundant nullcheck

16. Violation examples
• Empty if statement

17. Managing violations
• For each violation you can
– Comment
– Change its severity
– Declare it as a false-positive
– Assign it to someone
– Assign it to an action plan

18. Time machine

19. Technical debt
• Term coined by Ward Cunningham in 1992
• Work that needs done before a job is complete
• Unwritten tests
• Bad design and architecture
• Duplicated code
• …
• The higher you wait to fix, the more expensive it
becomes

20. SQALE
• Based on ISO 9126 Quality Model
• Computes a Technical Debt, measured in days

21. Code quality
“A well-written program is a program where
the cost of implementing a feature is
constant throughout the program's lifetime.”

22. What now?
• What to start with?
– Improving test coverage?
– Removing duplicate code?
– Checking violations?
– …
• Where to start?
– Most critical projects?
– Most « buggy » projects?
– Voluntary teams?
– …
Try it and tell me!