docs: public void setTransactionIsolationLevel(int iso) throws SQLException {
          if (!changable) {
              throw new SQLException(AdapterUtil.getNLSMessage("WS_INTERNAL_ERROR", 
                                                               "ConnectionRequestInfo cannot be modified, doing so may result in corruption: iso , cri", iso, this));
  
          }
  
          if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled())
              Tr.debug(this, tc, "Setting isolation level on the CRI to:", iso);
          ivIsoLevel = iso;
      }