Maven: A Developer's Notebook

Reporting on Code Best Practices

When you're working in a team it's good to define development best practices to be used by all the developers. That's great, but how do you enforce their usage? Code reviews? Nah, that's the old way of doing it! Nowadays there are powerful tools to help verify that best practices are applied throughout the code. Some of these tools include Checkstyle (http://checkstyle.sourceforge.net/), PMD (http://pmd.sourceforge.net/), and Findbugs (http://findbugs.sourceforge.net/).^[2] Let's discover how to use the Checkstyle plug-in.

How do I do that?

Add a Checkstyle report to the qotd/core project's POM:

  <reports>
    <report>maven-checkstyle-plugin</report>
    [...]

If you run maven site now you'll get a Checkstyle report, as shown in Figure 4-6. Notice that the cells in Line column can be clicked. They are links to the JXR report described earlier, showing the code lines causing the violation.

Figure 4-6. Typical Checkstyle report

You may wonder where the rules to apply have been defined. By default the Checkstyle plug-in uses a default configuration file. However, it's very unlikely it'll match your project's coding conventions. You'll need to customize it by adding a property in qotd/core/project.properties, pointing to a Checkstyle XML configuration file:

maven.checkstyle.properties = ${basedir}/../common/checkstyle.xml

Tip

Don't forget that you must use ${basedir} ...