code: public void addAnnotation(final Class<? extends Annotation> clazz, final Annotation ann) {
          if (ann == null || clazz == null) {
              return;
          }
  
          if (!foundAnnotations.containsKey(clazz)) {
              foundAnnotations.put(clazz, new ArrayList<Annotation>());
          }
  
          foundAnnotations.get(clazz).add(ann);
      }
docs: Adds the given Annotation to the internal list for the given Class.
  
  @param clazz the type to add
  @param ann   the annotation to add