docs: public static UserRegistry getUserRegistry(String realmName) throws WSSecurityException {
          try {
              WSSecurityService ss = wsSecurityServiceRef.getService();
              if (ss == null) {
                  if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled()) {
                      Tr.debug(tc, "No WSSecurityService, returning null");
                  }
              } else {
                  return ss.getUserRegistry(realmName);
              }
          } catch (WSSecurityException e) {
              String msg = "getUserRegistry for realm " + realmName + " failed due to an internal error: " + e.getMessage();
              if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled()) {
                  Tr.debug(tc, msg, e);
              }
              throw new WSSecurityException(msg, e);
          }
          return null;
      }