内容一:文章详情直接从db拿，而点赞用户列表其实就是从哈希数据结构Hash获取即可。
内容二:获取当前用户是否已经点赞过当前的文章 - 其实就是contains方法的调用而已。
PraiseService.java
//获取文章详情-点赞过的用户列表-排行榜 public Map<String,Object> getArticleInfo(final Integer articleId,final Integer currUserId) throws Exception{ Map<String,Object> resMap= Maps.newHashMap(); //获取文章详情 resMap.put("articleInfo~文章详情",articleMapper.selectByPK(articleId)); //获取点赞过文章的用户列表 ~ 获取昵称 ~[10010,10011,10012...]~张三,李四,王五... HashOperations<String,String,Set<Integer>> praiseHash=redisTemplate.opsForHash(); Set<Integer> uIds=praiseHash.get(Constant.RedisArticlePraiseHashKey,articleId.toString()); if (uIds!=null && !uIds.isEmpty()){ resMap.put("userIds~用户id列表",uIds); String ids= Joiner.on(",").join(uIds);//转换成字符串常量 resMap.put("userIds~用户昵称列表",userMapper.selectNamesById(ids)); //当前用户currUserId是否点赞过当前文章 if (currUserId!=null){ resMap.put("currUserHasPraise-当前用户是否点赞过该文章",uIds.contains(currUserId)); } } } articleMapper.selectByPK(articleId)对应的xml文件 <select id="selectByPK" resultType="com.redis.model.entity.Article"> select a.*, b.name as userName from article as a left join user as b on b.id = a.user_id where a.is_active = 1 and a.id=#{articleId} order by a.create_time desc </select> userMapper.selectNamesById(ids) <select id="selectNamesById" resultType="java.lang.String"> select group_concat(name) from user where id in(${ids}) </select>在sql中直接对某篇文章点赞过的所用用户进行拼接，然后返回一个字符串，而不是返回一个list集合。利用group_concat()函数
