The Components We Develop Are Not Used at All! Or Are They?


Developing component based software is cool. But which of the developed components are actually used?
Most of the time it is uncertain. A similar uncertainty emerges with regression tests. Are the bug-fixes actually tested?

To some developers these information might not be interesting. As much more it is for decision makers.
We use JaCoCo for gathering this usage/test data.
Hurdles are:

  • Actually get the usage data - How do you access it
  • Different codebases of the run application (releases, even bug-fixes)
  • Relationship of packages to components
  • Visualization on a component basis

With a little package-component-mapping we can get more certainty, whether which component is actually used, or tested. With additional report formatting it is easy to understand. Even management could comprehend.

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Hi Achim,

sorry for the delayed answer.

I want to show, that JaCoCo reporting can also be interesting for stakeholders, other than developers. E.g. for project leads or the like.
Points of interest are:
- which components are actually used by the application's user (in a more abstract level than package or project)
- respectively, if the changed components (e.g. after an enhancement or bug-fix) are actually tested by hallway testers

For all stakeholders the reports are generated in an abstract manner to meet an easy comprehendible need.

So I'll show how to do it and what it looks like.

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