Don't declare unused variable
Remove unused @SuppressWarning("unchecked")
Remove unused method ExporterAttributes.pathOrNull(String)
Replace deprecated JavaConventions.validatePackageName(String) by JavaConventions.validatePackageName(String, String, String)
Replace deprecated method WorkspaceRoot.findContainersForLocation(IPath) by WorkspaceRoot.findContainersForLocationURI(URI)
Use generic parameters for Set and HashSet