code: private String getRealmName() {
          String realm = "defaultRealm";
          try {
              UserRegistry ur = RegistryHelper.getUserRegistry(null);
              if (ur != null) {
                  String r = ur.getRealm();
                  if (r != null) {
                      realm = r;
                  }
              }
          } catch (Exception ex) {
              if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled()) {
                  Tr.debug(tc, "Cannot get the UR service since it may not be available so use the default value for the realm.", ex);
              }
          }
  
          return realm;
      }
docs: Obtains the realm name of the configured UserRegistry, if one is available.
  
  @return The configured realm name, or "defaultRealm" if no UserRegistry is present