Sometimes I put the class name in the comments of methods or class just for referencing. But eclipse does the import automatically and leaves an import statement in the file whi
People don't agree whether this is a bug or not. Javadoc needs the imports to create appropriate links. I'd say checkstyle should provide an option (and Eclipse maybe too) to change the warning.
There are two relevant bug reports:
Update: The mentioned bug has been fixed in checkstyle. You know have the option to configure the behavior.