Mybatis实现分页查询的详细流程

// SQL语句
select * from student limit(currentPage-1)*pageSize,pageSize;

@select("select * from student limit #{pageBegin},#{pageSize}")
List<Student> findByPage(@Param("pageBegin") Integer PageBegin,@Param("PageSize")Integer PageSize);

@GetMapping("/findByPage")
public List<Student> findByPage(Integer page,Integer pageSize){
    Integer pageBegin = (page-1) * pageSize;
    return StudentMapper.findByPage(pageBegin,pageSize);
}

/**
 * 分页结果封装对象
 */
@AllArgsConstructor
@NoArgsConstructor
@Data
public class PageResult implements Serializable{
    private Long total;//总记录数
    private List rows;//当前页结果
}

// 分页请求。
@AllArgsConstructor
@NoArgsConstructor
@Data
public class QueryPageBean implements Serializable{
    private Integer currentPage;//当前页码
    private Integer pageSize;//每页记录数
    private String queryString;//查询条件
    public QueryPageBean(Integer currentPage, Integer pageSize) {
        this.currentPage = currentPage;
        this.pageSize = pageSize;
    }
}

/*** 持久层Dao接口 */
@Mapper
public interface CheckGroupDao {
    public Page<CheckGroup> selectByCondition(String queryString);
}

<!--动态查询：分页查询-->
    <select id="selectByCondition" parameterType="string" resultType="com.apesource.graduation_project.pojo.CheckGroup">
        select * from t_checkgroup
        <if test="value != null and value.length > 0">
            where code = #{value} or name = #{value} or helpCode = #{value}
        </if>
    </select>

@Override
    public PageResult pageQuery(Integer currentPage, Integer pageSize, String queryString)             　　　　　　　　{
        PageHelper.startPage(currentPage, pageSize);
        Page<CheckGroup> page = checkGroupDao.selectByCondition(queryString);
        return new PageResult(page.getTotal(), page.getResult());
    }

 //分页查询
    @PostMapping("/findPage")
    public PageResult findPage(@RequestBody QueryPageBean queryPageBean) {
        try {
            PageResult pageResult = checkGroupService.pageQuery(queryPageBean.getCurrentPage(),queryPageBean.getPageSize(),queryPageBean.getQueryString());
            return pageResult;
        } catch (Exception e) {
            return null;
        }
    }