docs: private void checkLocking(FieldDescriptorDef fieldDef, String checkLevel) throws ConstraintException
      {
          if (CHECKLEVEL_NONE.equals(checkLevel))
          {
              return;
          }
  
          String jdbcType = fieldDef.getProperty(PropertyHelper.OJB_PROPERTY_JDBC_TYPE);
  
          if (!"TIMESTAMP".equals(jdbcType) && !"INTEGER".equals(jdbcType))
          {
              if (fieldDef.getBooleanProperty(PropertyHelper.OJB_PROPERTY_LOCKING, false))
              {
                  throw new ConstraintException("The field "+fieldDef.getName()+" in class "+fieldDef.getOwner().getName()+" has locking set to true though it is not of TIMESTAMP or INTEGER type");
              }
              if (fieldDef.getBooleanProperty(PropertyHelper.OJB_PROPERTY_UPDATE_LOCK, false))
              {
                  throw new ConstraintException("The field "+fieldDef.getName()+" in class "+fieldDef.getOwner().getName()+" has update-lock set to true though it is not of TIMESTAMP or INTEGER type");
              }
          }
      }