code: private static boolean hasAnnotation(String pkgInfo, String annotation) {
      if (!annotation.contains(".")) {
        ErrorUtil.warning(annotation + " is not a fully qualified name");
      }
      if (pkgInfo.contains("@" + annotation)) {
        return true;
      }
      int idx = annotation.lastIndexOf(".");
      String annotationPackageName = annotation.substring(0, idx);
      String annotationSimpleName = annotation.substring(idx + 1);
      if (pkgInfo.contains("@" + annotationSimpleName)) {
        String importRegex =
            "import\\s*" + annotationPackageName + "(\\.\\*|\\." + annotationSimpleName + ")";
        Pattern p = Pattern.compile(importRegex);
        Matcher m = p.matcher(pkgInfo);
        if (m.find()) {
          return true;
        }
      }
      return false;
    }
docs: Return true if pkgInfo has the specified annotation.
  
  @param pkgInfo package-info source code
  @param annotation fully qualified name of the annotation