docs: private void isInitialized(boolean condition, String propName) {
          if (condition == true) {
              IllegalStateException e = new IllegalStateException("J2CGlobalConfigProperties: internal error.  Set once property already set.");
              Tr.error(tc, "SET_ONCE_PROP_ALREADY_SET_J2CA0159", (Object) null);
              throw e;
          }
      }