@Nullable @Override public LessonLinkVO updateByOrderNum( @NotNull Long courseId, @NotNull Long lessonOrderNum, @NotNull Long orderNum, LessonLinkVO lessonLink) { return convertEntityToVO( lessonLinkDAO.updateByOrderNum( lessonDAO.getByOrderNum(courseId, lessonOrderNum), orderNum, convertVOToEntity(lessonLink))); }