code: public static int getIsolationLevel(Object obj)
      {
          Class c = ProxyHelper.getRealClass(obj);
          int isolationLevel = IsolationLevels.IL_READ_UNCOMMITTED;
  
          try
          {
              ClassDescriptor cld = TxManagerFactory.instance().getCurrentTransaction().getBroker().getClassDescriptor(c);
              isolationLevel = cld.getIsolationLevel();
          }
          catch (PersistenceBrokerException e)
          {
              LoggerFactory.getDefaultLogger().error("[LockStrategyFactory] Can't detect locking isolation level", e);
          }
          return isolationLevel;
      }
docs: determines the isolationlevel of class c by evaluating
  the ClassDescriptor of obj.getClass().
  
  @return int the isolationlevel