拉姆达Lambda表达式对list分页，获取list总页数

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    @Override
    public IPage<FreeEntity> queryFreeList(FreeQuery freeQuery) {
        String tag = redisTemplate.opsForHash().get("REDIS_DIC:af_server_suffix", freeQuery.getServerId()).toString();
        String freeListResult = (String) redisTemplate.opsForHash().get(GeneralConstant.FREELIST + freeQuery.getTenantId(),
                freeQuery.getTenantId() + tag);
        List<FreeEntity> freeList = JSONObject.parseArray(freeListResult, FreeEntity.class);
        List<FreeEntity> entityList = freeList.stream().skip(freeQuery.getPageSize() * (freeQuery.getPageNum() - 1)).limit(freeQuery.getPageSize()).collect(Collectors.toList());
        Page<FreeEntity> freeEntityPage = new Page<>();
        //总条数
        freeEntityPage.setTotal(freeList.size());
        //列表
        freeEntityPage.setRecords(entityList);
        //当前页
        freeEntityPage.setCurrent(freeQuery.getPageNum());
        //行数
        freeEntityPage.setSize(freeQuery.getPageSize());
        //总页数
        freeEntityPage.setPages(getPages(freeList, freeQuery.getPageSize()));
        return freeEntityPage;
    }

    /**
     * 返回总页数
     *
     * @param obj
     * @param pageSize
     * @return
     */
    public int getPages(List<FreeEntity> obj, Integer pageSize) {
        int count = obj.size() / pageSize;
        if (obj.size() == 0) {
            return 0;
        }
        if (obj.size() <= pageSize) {
            return 1;
        } else if (count % pageSize == 0) {
            return count;
        } else {
            return count + 1;
        }
    }