private static void invokeInner(Project project, PsiElement[] elements, Editor editor) {
    Set<GroovyFile> files = new HashSet<>();

    for (PsiElement element : elements) {
      if (!(element instanceof PsiFile)) {
        element = element.getContainingFile();
      }

      if (element instanceof GroovyFile) {
        files.add((GroovyFile)element);
      }
      else {
        if (!ApplicationManager.getApplication().isUnitTestMode()) {
          CommonRefactoringUtil.showErrorHint(
            project, editor,
            GroovyRefactoringBundle.message("convert.to.java.can.work.only.with.groovy"),
            GroovyRefactoringBundle.message("convert.to.java.refactoring.name"),
            null
          );
          return;
        }
      }
    }

    new ConvertToJavaProcessor(project, files.toArray(GroovyFile.EMPTY_ARRAY)).run();
  }
private static void invokeInner(Project project, PsiElement[] elements, Editor editor)