//分页查找
public Page queryManagersByPage(int currentPage, int pageSize) throws IOException {
    
    
    SqlSession session = genenalMapper.useSqlSession();
    ManagerMapper mm = genenalMapper.getMapper(session,  ManagerMapper.class);
    Page<Object> page = PageHelper.startPage(currentPage, pageSize);
    List<Manager> list = mm.queryManagers();
    return page;
}

//Page查询元素为空，但是调试过程中数据库表中数据有2条，但是返回page和list为[null][null];
**2.原因**
Manager的实体类与数据库表中字段不一致