A useful thing that a build server can do is the collation of software quality metrics. Jenkins has some support for this out of the box. Java unit tests are executed and can be visualized directly on the job page.
Another more advanced option is using the Sonar code quality visualizer, which is shown in the following screenshot. Sonar tests are run during the build phase and propagated to the Sonar server, where they are stored and visualized.
A Sonar server can be a great way for a development team to see the fruits of their efforts at improving the code base.
The drawback of implementing a Sonar server is that it sometimes slows down the builds. The recommendation is to perform the Sonar builds in your nightly builds, once a day.
The following screenshot shows some of Sonar's many different code metrics, from simple ones like the number of lines...
