code: Map<Class<? extends Annotation>, Set<Locale>> getAnnotationToLocaleMapping() {
          Map<Class<? extends Annotation>, Set<Locale>> res = new HashMap<Class<? extends Annotation>, Set<Locale>>();
          for (Entry<Class<? extends Annotation>, C10NAnnotationBinder> entry : annotationBinders.entrySet()) {
              Set<Locale> locales = getLocales(entry.getKey(), res);
              locales.add(entry.getValue().getLocale());
          }
          return res;
      }
docs: For each annotation bound in this configuration find all
  locales it has been bound to.
  
  @return annotation -&gt; set of locale mapping