private String getBundleKey(String name) {
        Locale bestLocale = localeMatcher.getBestLocale(getLocale());
        if (bestLocale != null) {
            return name + "::" + bestLocale;
        } else {
            return name + "::en";
        }
    }
Gets the key to use into the cache of bundles.  The key is made up of the
fully qualified class name and the locale.
common/util/src/main/java/io/apiman/common/util/AbstractMessages.java