How to Resolve SpotBugs Gradle Plugin Groovy SDK Errors in Java Builds

While performing static analysis on a Java project with the SpotBugs plugin, the build sometimes fails with the error

Error:Cannot compile Groovy files: no Groovy library is defined for module '****'

. The user initially wondered why SpotBugs reported No Groovy files even though the project contains no Groovy source files.

Investigation revealed that the spotbugs-gradle-plugin itself is written in Groovy, and Gradle is also based on Groovy. Because the plugin does not find a Groovy SDK in the IDE, the compilation step aborts.

Solution: Add a Groovy SDK to the project:

Open File → Project Structure in the IDE.

Select Global Libraries and click the plus button.

Choose Java (the exact label may vary) and then browse to a local Groovy SDK installation.

Use the lib directory inside the Groovy SDK rather than the root directory.

After adding the Groovy SDK, rebuild the project; the error disappears and the build succeeds.