code: protected Map<String, String> getMpConfigMap(MpConfigProxyService service, ClassLoader cl, Map<String, String> map) {
          Arrays.asList(MpConstants.ISSUER, MpConstants.PUBLIC_KEY, MpConstants.KEY_LOCATION).forEach(s -> getMpConfig(service, cl, s, map));
          return map;
      }
docs: no null check. make sure that the caller sets non null objects.