code:     protected void checkIllegalTypes(DeserializationContext ctxt, JavaType type,
              BeanDescription beanDesc)
          throws JsonMappingException
      {
          // There are certain nasty classes that could cause problems, mostly
          // via default typing -- catch them here.
          String full = type.getRawClass().getName();
  
          if (_cfgIllegalClassNames.contains(full)) {
              ctxt.reportBadTypeDefinition(beanDesc,
                      "Illegal type (%s) to deserialize: prevented for security reasons", full);
          }
      }
  