java中List分页的几种方法介绍

         Criteria criteria = new Criteria();
         //将dataAuto转成 factoryId brandId seriesId 等查询条件
         String dataAuth = "";
         TypeCaseHelper.dataAuto(criteria, dataAuth);
         // 设置分页信息
         ExtPager pager = new ExtPager();
         Integer startTure = start * pageSize;
         criteria.setMysqlPageSize(pageSize);
         criteria.setmysqlStart(startTure);
         // 排序信息
         if (StringUtils.isNotBlank(pager.getDir()) && StringUtils.isNotBlank(pager.getSort())) {
             criteria.setOrderByClause(pager.getSort() + " " + pager.getDir());
         }
         List<VhlAlarmStatusMgtEntity> listDistinct = getVhlAlarmStatusMgtEntities(vin, faultStatus, confirmStatus, startDateTime, endDateTime, sdf, sdfm, carTypeList, criteria);

  <select id="selectByExample" parameterType="Criteria" resultMap="BaseResultMap">
    select
    <include refid="Base_Column_List" />
    from status_mgt
    <where>
      <if test="condition.carTypeList != null and condition.carTypeList.size() > 0" >
        and car_type in
        <foreach collection="condition.carTypeList" item="item"  open="(" separator="," close=")">
          #{item}
        </foreach>
      </if>
      <if test="condition.startDateTime != null and condition.startDateTime!=''">
        and alarm_time >= str_to_date(#{condition.startDateTime,jdbcType=VARCHAR},'%Y-%m-%d %H:%i:%S')
      </if>
      <if test="condition.endDateTime != null and condition.endDateTime!=''">
        and  str_to_date(#{condition.endDateTime,jdbcType=VARCHAR},'%Y-%m-%d %H:%i:%S') >= alarm_time
      </if>
      and logic_flag = 1
    </where>
    order by alarm_time desc
    <if test="mysqlStart != null  and mysqlPageSize != null">
        limit #{mysqlStart}, #{mysqlPageSize}
    </if>
 
  </select>

         Criteria criteria1 = new Criteria();
         List<VhlAlarmStatusMgtEntity> listDistinctForCout = getVhlAlarmStatusMgtEntities(vin, faultStatus, confirmStatus, startDateTime, endDateTime, sdf, sdfm, carTypeList, criteria1);
         Integer count = listDistinctForCout.size(); // 记录总数
         Integer pageCount; // 页数
         if (count % pageSize == 0) {
             pageCount = count / pageSize;
         } else {
             pageCount = count / pageSize + 1;
         }
         int fromIndex; // 开始索引
         int toIndex; // 结束索引
         if (!pageCount.equals(start+1)) {
             fromIndex = start * pageSize;
             toIndex = fromIndex + pageSize;
             if(toIndex > count){
                 fromIndex = (start-1) * pageSize;
                 toIndex = count;
             }
         } else {
             fromIndex = start * pageSize;
             toIndex = count;
         }
         List<VhlAlarmStatusMgtEntity> pageList = listDistinctForCout.subList(fromIndex, toIndex);

      //开启分页
        PageHelper.startPage(Integer.parseInt(pageNum), Integer.parseInt(pageSize));
 
        PageInfo<Map<String, String>> pageInfo = new PageInfo(datalist);
 
        HashMap<String, Object> map= new HashMap<>();
        map.put("datalist", datalist);
        map.put("total", pageInfo.getTotal());
        map.put("size", pageInfo.getPageSize());
        map.put("page", pageInfo.getPageNum());