This exception notifies you of a deeper problem while trying to load a goal from its plugin class path. Possible causes for this can be:
To check whether the plugin JAR and its POM are intact, inspect your local repository which is usually located at ${user.home}/.m2/repository
. For a plugin with the coordinates com.company:custom-maven-plugin:1.0
, the file to check is com/company/custom-maven-plugin/1.0/custom-maven-plugin-1.0.jar
and custom-maven-plugin-1.0.pom
, respectively. If those files don't match the copies in the plugin repository, e.g. as noticeable by checksum mismatches, simply delete the local files and have Maven re-download it.
In case of custom plugin dependencies, please verify that the version of the custom dependencies you specified are compatible with the plugin version you employ. One way to do this is to check the versions of the dependencies that the plugin natively uses. For a plugin site that is generated by Maven, this information can be accessed via "Project Information" > "Dependencies" from the left navigation bar. The documentation for many common Maven plugins can be reached via our plugin index.