泛型转换Class问题

public class BaseOperationResource<Service extends BaseOperationService, Repository extends BaseRepository, QueryService, DTO extends BaseDTO> extends BaseResource<Service, Repository, QueryService> {

private Class<DTO> dtoClass;

public BaseOperationResource(){
    Type genType = getClass().getGenericSuperclass();
    Type[] params = ((ParameterizedType) genType).getActualTypeArguments();
    dtoClass = (Class) params[3];
}
}